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Adding browsable prebuilt samples for march push

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Change-Id: I952db10d9c9acb4940db08a07789347ea2effe4d
This commit is contained in:
Alexander Lucas
2014-03-07 13:34:45 -08:00
parent 7cd4524c3b
commit a780ba4b15
213 changed files with 15681 additions and 93 deletions
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236
samples/browseable/DisplayingBitmaps/src/com.example.android.common.logger/Log.java Normal file
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/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.common.logger;
/**
* Helper class for a list (or tree) of LoggerNodes.
*
* <p>When this is set as the head of the list,
* an instance of it can function as a drop-in replacement for {@link android.util.Log}.
* Most of the methods in this class server only to map a method call in Log to its equivalent
* in LogNode.</p>
*/
public class Log {
// Grabbing the native values from Android's native logging facilities,
// to make for easy migration and interop.
public static final int NONE = -1;
public static final int VERBOSE = android.util.Log.VERBOSE;
public static final int DEBUG = android.util.Log.DEBUG;
public static final int INFO = android.util.Log.INFO;
public static final int WARN = android.util.Log.WARN;
public static final int ERROR = android.util.Log.ERROR;
public static final int ASSERT = android.util.Log.ASSERT;
// Stores the beginning of the LogNode topology.
private static LogNode mLogNode;
/**
* Returns the next LogNode in the linked list.
*/
public static LogNode getLogNode() {
return mLogNode;
}
/**
* Sets the LogNode data will be sent to.
*/
public static void setLogNode(LogNode node) {
mLogNode = node;
}
/**
* Instructs the LogNode to print the log data provided. Other LogNodes can
* be chained to the end of the LogNode as desired.
*
* @param priority Log level of the data being logged. Verbose, Error, etc.
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void println(int priority, String tag, String msg, Throwable tr) {
if (mLogNode != null) {
mLogNode.println(priority, tag, msg, tr);
}
}
/**
* Instructs the LogNode to print the log data provided. Other LogNodes can
* be chained to the end of the LogNode as desired.
*
* @param priority Log level of the data being logged. Verbose, Error, etc.
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged. The actual message to be logged.
*/
public static void println(int priority, String tag, String msg) {
println(priority, tag, msg, null);
}
/**
* Prints a message at VERBOSE priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void v(String tag, String msg, Throwable tr) {
println(VERBOSE, tag, msg, tr);
}
/**
* Prints a message at VERBOSE priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
*/
public static void v(String tag, String msg) {
v(tag, msg, null);
}
/**
* Prints a message at DEBUG priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void d(String tag, String msg, Throwable tr) {
println(DEBUG, tag, msg, tr);
}
/**
* Prints a message at DEBUG priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
*/
public static void d(String tag, String msg) {
d(tag, msg, null);
}
/**
* Prints a message at INFO priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void i(String tag, String msg, Throwable tr) {
println(INFO, tag, msg, tr);
}
/**
* Prints a message at INFO priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
*/
public static void i(String tag, String msg) {
i(tag, msg, null);
}
/**
* Prints a message at WARN priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void w(String tag, String msg, Throwable tr) {
println(WARN, tag, msg, tr);
}
/**
* Prints a message at WARN priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
*/
public static void w(String tag, String msg) {
w(tag, msg, null);
}
/**
* Prints a message at WARN priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void w(String tag, Throwable tr) {
w(tag, null, tr);
}
/**
* Prints a message at ERROR priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void e(String tag, String msg, Throwable tr) {
println(ERROR, tag, msg, tr);
}
/**
* Prints a message at ERROR priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
*/
public static void e(String tag, String msg) {
e(tag, msg, null);
}
/**
* Prints a message at ASSERT priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void wtf(String tag, String msg, Throwable tr) {
println(ASSERT, tag, msg, tr);
}
/**
* Prints a message at ASSERT priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged.
*/
public static void wtf(String tag, String msg) {
wtf(tag, msg, null);
}
/**
* Prints a message at ASSERT priority.
*
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public static void wtf(String tag, Throwable tr) {
wtf(tag, null, tr);
}
}

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samples/browseable/DisplayingBitmaps/src/com.example.android.common.logger/LogFragment.java Normal file
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/*
* Copyright 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
/*
* Copyright 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.common.logger;
import android.graphics.Typeface;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.text.Editable;
import android.text.TextWatcher;
import android.view.Gravity;
import android.view.LayoutInflater;
import android.view.View;
import android.view.ViewGroup;
import android.widget.ScrollView;
/**
* Simple fraggment which contains a LogView and uses is to output log data it receives
* through the LogNode interface.
*/
public class LogFragment extends Fragment {
private LogView mLogView;
private ScrollView mScrollView;
public LogFragment() {}
public View inflateViews() {
mScrollView = new ScrollView(getActivity());
ViewGroup.LayoutParams scrollParams = new ViewGroup.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT,
ViewGroup.LayoutParams.MATCH_PARENT);
mScrollView.setLayoutParams(scrollParams);
mLogView = new LogView(getActivity());
ViewGroup.LayoutParams logParams = new ViewGroup.LayoutParams(scrollParams);
logParams.height = ViewGroup.LayoutParams.WRAP_CONTENT;
mLogView.setLayoutParams(logParams);
mLogView.setClickable(true);
mLogView.setFocusable(true);
mLogView.setTypeface(Typeface.MONOSPACE);
// Want to set padding as 16 dips, setPadding takes pixels. Hooray math!
int paddingDips = 16;
double scale = getResources().getDisplayMetrics().density;
int paddingPixels = (int) ((paddingDips * (scale)) + .5);
mLogView.setPadding(paddingPixels, paddingPixels, paddingPixels, paddingPixels);
mLogView.setCompoundDrawablePadding(paddingPixels);
mLogView.setGravity(Gravity.BOTTOM);
mLogView.setTextAppearance(getActivity(), android.R.style.TextAppearance_Holo_Medium);
mScrollView.addView(mLogView);
return mScrollView;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
View result = inflateViews();
mLogView.addTextChangedListener(new TextWatcher() {
@Override
public void beforeTextChanged(CharSequence s, int start, int count, int after) {}
@Override
public void onTextChanged(CharSequence s, int start, int before, int count) {}
@Override
public void afterTextChanged(Editable s) {
mScrollView.fullScroll(ScrollView.FOCUS_DOWN);
}
});
return result;
}
public LogView getLogView() {
return mLogView;
}
}

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samples/browseable/DisplayingBitmaps/src/com.example.android.common.logger/LogNode.java Normal file
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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.common.logger;
/**
* Basic interface for a logging system that can output to one or more targets.
* Note that in addition to classes that will output these logs in some format,
* one can also implement this interface over a filter and insert that in the chain,
* such that no targets further down see certain data, or see manipulated forms of the data.
* You could, for instance, write a "ToHtmlLoggerNode" that just converted all the log data
* it received to HTML and sent it along to the next node in the chain, without printing it
* anywhere.
*/
public interface LogNode {
/**
* Instructs first LogNode in the list to print the log data provided.
* @param priority Log level of the data being logged. Verbose, Error, etc.
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged. The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
public void println(int priority, String tag, String msg, Throwable tr);
}

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samples/browseable/DisplayingBitmaps/src/com.example.android.common.logger/LogView.java Normal file
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/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.common.logger;
import android.app.Activity;
import android.content.Context;
import android.util.*;
import android.widget.TextView;
/** Simple TextView which is used to output log data received through the LogNode interface.
*/
public class LogView extends TextView implements LogNode {
public LogView(Context context) {
super(context);
}
public LogView(Context context, AttributeSet attrs) {
super(context, attrs);
}
public LogView(Context context, AttributeSet attrs, int defStyle) {
super(context, attrs, defStyle);
}
/**
* Formats the log data and prints it out to the LogView.
* @param priority Log level of the data being logged. Verbose, Error, etc.
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged. The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
@Override
public void println(int priority, String tag, String msg, Throwable tr) {
String priorityStr = null;
// For the purposes of this View, we want to print the priority as readable text.
switch(priority) {
case android.util.Log.VERBOSE:
priorityStr = "VERBOSE";
break;
case android.util.Log.DEBUG:
priorityStr = "DEBUG";
break;
case android.util.Log.INFO:
priorityStr = "INFO";
break;
case android.util.Log.WARN:
priorityStr = "WARN";
break;
case android.util.Log.ERROR:
priorityStr = "ERROR";
break;
case android.util.Log.ASSERT:
priorityStr = "ASSERT";
break;
default:
break;
}
// Handily, the Log class has a facility for converting a stack trace into a usable string.
String exceptionStr = null;
if (tr != null) {
exceptionStr = android.util.Log.getStackTraceString(tr);
}
// Take the priority, tag, message, and exception, and concatenate as necessary
// into one usable line of text.
final StringBuilder outputBuilder = new StringBuilder();
String delimiter = "\t";
appendIfNotNull(outputBuilder, priorityStr, delimiter);
appendIfNotNull(outputBuilder, tag, delimiter);
appendIfNotNull(outputBuilder, msg, delimiter);
appendIfNotNull(outputBuilder, exceptionStr, delimiter);
// In case this was originally called from an AsyncTask or some other off-UI thread,
// make sure the update occurs within the UI thread.
((Activity) getContext()).runOnUiThread( (new Thread(new Runnable() {
@Override
public void run() {
// Display the text we just generated within the LogView.
appendToLog(outputBuilder.toString());
}
})));
if (mNext != null) {
mNext.println(priority, tag, msg, tr);
}
}
public LogNode getNext() {
return mNext;
}
public void setNext(LogNode node) {
mNext = node;
}
/** Takes a string and adds to it, with a separator, if the bit to be added isn't null. Since
* the logger takes so many arguments that might be null, this method helps cut out some of the
* agonizing tedium of writing the same 3 lines over and over.
* @param source StringBuilder containing the text to append to.
* @param addStr The String to append
* @param delimiter The String to separate the source and appended strings. A tab or comma,
* for instance.
* @return The fully concatenated String as a StringBuilder
*/
private StringBuilder appendIfNotNull(StringBuilder source, String addStr, String delimiter) {
if (addStr != null) {
if (addStr.length() == 0) {
delimiter = "";
}
return source.append(addStr).append(delimiter);
}
return source;
}
// The next LogNode in the chain.
LogNode mNext;
/** Outputs the string as a new line of log data in the LogView. */
public void appendToLog(String s) {
append("\n" + s);
}
}

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samples/browseable/DisplayingBitmaps/src/com.example.android.common.logger/LogWrapper.java Normal file
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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.common.logger;
import android.util.Log;
/**
* Helper class which wraps Android's native Log utility in the Logger interface. This way
* normal DDMS output can be one of the many targets receiving and outputting logs simultaneously.
*/
public class LogWrapper implements LogNode {
// For piping: The next node to receive Log data after this one has done its work.
private LogNode mNext;
/**
* Returns the next LogNode in the linked list.
*/
public LogNode getNext() {
return mNext;
}
/**
* Sets the LogNode data will be sent to..
*/
public void setNext(LogNode node) {
mNext = node;
}
/**
* Prints data out to the console using Android's native log mechanism.
* @param priority Log level of the data being logged. Verbose, Error, etc.
* @param tag Tag for for the log data. Can be used to organize log statements.
* @param msg The actual message to be logged. The actual message to be logged.
* @param tr If an exception was thrown, this can be sent along for the logging facilities
* to extract and print useful information.
*/
@Override
public void println(int priority, String tag, String msg, Throwable tr) {
// There actually are log methods that don't take a msg parameter. For now,
// if that's the case, just convert null to the empty string and move on.
String useMsg = msg;
if (useMsg == null) {
useMsg = "";
}
// If an exeption was provided, convert that exception to a usable string and attach
// it to the end of the msg method.
if (tr != null) {
msg += "\n" + Log.getStackTraceString(tr);
}
// This is functionally identical to Log.x(tag, useMsg);
// For instance, if priority were Log.VERBOSE, this would be the same as Log.v(tag, useMsg)
Log.println(priority, tag, useMsg);
// If this isn't the last node in the chain, move things along.
if (mNext != null) {
mNext.println(priority, tag, msg, tr);
}
}
}

60
samples/browseable/DisplayingBitmaps/src/com.example.android.common.logger/MessageOnlyLogFilter.java Normal file
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/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.common.logger;
/**
* Simple {@link LogNode} filter, removes everything except the message.
* Useful for situations like on-screen log output where you don't want a lot of metadata displayed,
* just easy-to-read message updates as they're happening.
*/
public class MessageOnlyLogFilter implements LogNode {
LogNode mNext;
/**
* Takes the "next" LogNode as a parameter, to simplify chaining.
*
* @param next The next LogNode in the pipeline.
*/
public MessageOnlyLogFilter(LogNode next) {
mNext = next;
}
public MessageOnlyLogFilter() {
}
@Override
public void println(int priority, String tag, String msg, Throwable tr) {
if (mNext != null) {
getNext().println(Log.NONE, null, msg, null);
}
}
/**
* Returns the next LogNode in the chain.
*/
public LogNode getNext() {
return mNext;
}
/**
* Sets the LogNode data will be sent to..
*/
public void setNext(LogNode node) {
mNext = node;
}
}

245
samples/browseable/DisplayingBitmaps/src/com.example.android.displayingbitmaps/provider/Images.java Normal file
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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.provider;
/**
* Some simple test data to use for this sample app.
*/
public class Images {
/**
* This are PicasaWeb URLs and could potentially change. Ideally the PicasaWeb API should be
* used to fetch the URLs.
*
* Credit to Romain Guy for the photos:
* http://www.curious-creature.org/
* https://plus.google.com/109538161516040592207/about
* http://www.flickr.com/photos/romainguy
*/
public final static String[] imageUrls = new String[] {
"https://lh6.googleusercontent.com/-55osAWw3x0Q/URquUtcFr5I/AAAAAAAAAbs/rWlj1RUKrYI/s1024/A%252520Photographer.jpg",
"https://lh4.googleusercontent.com/--dq8niRp7W4/URquVgmXvgI/AAAAAAAAAbs/-gnuLQfNnBA/s1024/A%252520Song%252520of%252520Ice%252520and%252520Fire.jpg",
"https://lh5.googleusercontent.com/-7qZeDtRKFKc/URquWZT1gOI/AAAAAAAAAbs/hqWgteyNXsg/s1024/Another%252520Rockaway%252520Sunset.jpg",
"https://lh3.googleusercontent.com/--L0Km39l5J8/URquXHGcdNI/AAAAAAAAAbs/3ZrSJNrSomQ/s1024/Antelope%252520Butte.jpg",
"https://lh6.googleusercontent.com/-8HO-4vIFnlw/URquZnsFgtI/AAAAAAAAAbs/WT8jViTF7vw/s1024/Antelope%252520Hallway.jpg",
"https://lh4.googleusercontent.com/-WIuWgVcU3Qw/URqubRVcj4I/AAAAAAAAAbs/YvbwgGjwdIQ/s1024/Antelope%252520Walls.jpg",
"https://lh6.googleusercontent.com/-UBmLbPELvoQ/URqucCdv0kI/AAAAAAAAAbs/IdNhr2VQoQs/s1024/Apre%2525CC%252580s%252520la%252520Pluie.jpg",
"https://lh3.googleusercontent.com/-s-AFpvgSeew/URquc6dF-JI/AAAAAAAAAbs/Mt3xNGRUd68/s1024/Backlit%252520Cloud.jpg",
"https://lh5.googleusercontent.com/-bvmif9a9YOQ/URquea3heHI/AAAAAAAAAbs/rcr6wyeQtAo/s1024/Bee%252520and%252520Flower.jpg",
"https://lh5.googleusercontent.com/-n7mdm7I7FGs/URqueT_BT-I/AAAAAAAAAbs/9MYmXlmpSAo/s1024/Bonzai%252520Rock%252520Sunset.jpg",
"https://lh6.googleusercontent.com/-4CN4X4t0M1k/URqufPozWzI/AAAAAAAAAbs/8wK41lg1KPs/s1024/Caterpillar.jpg",
"https://lh3.googleusercontent.com/-rrFnVC8xQEg/URqufdrLBaI/AAAAAAAAAbs/s69WYy_fl1E/s1024/Chess.jpg",
"https://lh5.googleusercontent.com/-WVpRptWH8Yw/URqugh-QmDI/AAAAAAAAAbs/E-MgBgtlUWU/s1024/Chihuly.jpg",
"https://lh5.googleusercontent.com/-0BDXkYmckbo/URquhKFW84I/AAAAAAAAAbs/ogQtHCTk2JQ/s1024/Closed%252520Door.jpg",
"https://lh3.googleusercontent.com/-PyggXXZRykM/URquh-kVvoI/AAAAAAAAAbs/hFtDwhtrHHQ/s1024/Colorado%252520River%252520Sunset.jpg",
"https://lh3.googleusercontent.com/-ZAs4dNZtALc/URquikvOCWI/AAAAAAAAAbs/DXz4h3dll1Y/s1024/Colors%252520of%252520Autumn.jpg",
"https://lh4.googleusercontent.com/-GztnWEIiMz8/URqukVCU7bI/AAAAAAAAAbs/jo2Hjv6MZ6M/s1024/Countryside.jpg",
"https://lh4.googleusercontent.com/-bEg9EZ9QoiM/URquklz3FGI/AAAAAAAAAbs/UUuv8Ac2BaE/s1024/Death%252520Valley%252520-%252520Dunes.jpg",
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"https://lh5.googleusercontent.com/-DRnqmK0t4VU/URqu8XYN9yI/AAAAAAAAAbs/LgvF_592WLU/s1024/Rice%252520Fields.jpg",
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"https://lh5.googleusercontent.com/-kI_QdYx7VlU/URqvLXCB6gI/AAAAAAAAAbs/N31vlZ6u89o/s1024/Yet%252520Another%252520Rockaway%252520Sunset.jpg",
"https://lh4.googleusercontent.com/-e9NHZ5k5MSs/URqvMIBZjtI/AAAAAAAAAbs/1fV810rDNfQ/s1024/Yosemite%252520Tree.jpg",
};
/**
* This are PicasaWeb thumbnail URLs and could potentially change. Ideally the PicasaWeb API
* should be used to fetch the URLs.
*
* Credit to Romain Guy for the photos:
* http://www.curious-creature.org/
* https://plus.google.com/109538161516040592207/about
* http://www.flickr.com/photos/romainguy
*/
public final static String[] imageThumbUrls = new String[] {
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"https://lh5.googleusercontent.com/-7qZeDtRKFKc/URquWZT1gOI/AAAAAAAAAbs/hqWgteyNXsg/s240-c/Another%252520Rockaway%252520Sunset.jpg",
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"https://lh5.googleusercontent.com/-n7mdm7I7FGs/URqueT_BT-I/AAAAAAAAAbs/9MYmXlmpSAo/s240-c/Bonzai%252520Rock%252520Sunset.jpg",
"https://lh6.googleusercontent.com/-4CN4X4t0M1k/URqufPozWzI/AAAAAAAAAbs/8wK41lg1KPs/s240-c/Caterpillar.jpg",
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"https://lh5.googleusercontent.com/-qSJ4D4iXzGo/URquyDWiJ1I/AAAAAAAAAbs/k2pBXeWehOA/s240-c/Leica%25252050mm%252520Summilux.jpg",
"https://lh6.googleusercontent.com/-dwlPg83vzLg/URquylTVuFI/AAAAAAAAAbs/G6SyQ8b4YsI/s240-c/Leica%252520M8%252520%252528Front%252529.jpg",
"https://lh3.googleusercontent.com/-R3_EYAyJvfk/URquzQBv8eI/AAAAAAAAAbs/b9xhpUM3pEI/s240-c/Light%252520to%252520Sand.jpg",
"https://lh3.googleusercontent.com/-fHY5h67QPi0/URqu0Cp4J1I/AAAAAAAAAbs/0lG6m94Z6vM/s240-c/Little%252520Bit%252520of%252520Paradise.jpg",
"https://lh5.googleusercontent.com/-TzF_LwrCnRM/URqu0RddPOI/AAAAAAAAAbs/gaj2dLiuX0s/s240-c/Lone%252520Pine%252520Sunset.jpg",
"https://lh3.googleusercontent.com/-4HdpJ4_DXU4/URqu046dJ9I/AAAAAAAAAbs/eBOodtk2_uk/s240-c/Lonely%252520Rock.jpg",
"https://lh6.googleusercontent.com/-erbF--z-W4s/URqu1ajSLkI/AAAAAAAAAbs/xjDCDO1INzM/s240-c/Longue%252520Vue.jpg",
"https://lh6.googleusercontent.com/-0CXJRdJaqvc/URqu1opNZNI/AAAAAAAAAbs/PFB2oPUU7Lk/s240-c/Look%252520Me%252520in%252520the%252520Eye.jpg",
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"https://lh6.googleusercontent.com/-flsqwMrIk2Q/URqu24PcmjI/AAAAAAAAAbs/5ocIH85XofM/s240-c/Marshall%252520Beach%252520Sunset.jpg",
"https://lh4.googleusercontent.com/-Y4lgryEVTmU/URqu28kG3gI/AAAAAAAAAbs/OjXpekqtbJ4/s240-c/Mono%252520Lake%252520Blue.jpg",
"https://lh4.googleusercontent.com/-AaHAJPmcGYA/URqu3PIldHI/AAAAAAAAAbs/lcTqk1SIcRs/s240-c/Monument%252520Valley%252520Overlook.jpg",
"https://lh4.googleusercontent.com/-vKxfdQ83dQA/URqu31Yq_BI/AAAAAAAAAbs/OUoGk_2AyfM/s240-c/Moving%252520Rock.jpg",
"https://lh5.googleusercontent.com/-CG62QiPpWXg/URqu4ia4vRI/AAAAAAAAAbs/0YOdqLAlcAc/s240-c/Napali%252520Coast.jpg",
"https://lh6.googleusercontent.com/-wdGrP5PMmJQ/URqu5PZvn7I/AAAAAAAAAbs/m0abEcdPXe4/s240-c/One%252520Wheel.jpg",
"https://lh6.googleusercontent.com/-6WS5DoCGuOA/URqu5qx1UgI/AAAAAAAAAbs/giMw2ixPvrY/s240-c/Open%252520Sky.jpg",
"https://lh6.googleusercontent.com/-u8EHKj8G8GQ/URqu55sM6yI/AAAAAAAAAbs/lIXX_GlTdmI/s240-c/Orange%252520Sunset.jpg",
"https://lh6.googleusercontent.com/-74Z5qj4bTDE/URqu6LSrJrI/AAAAAAAAAbs/XzmVkw90szQ/s240-c/Orchid.jpg",
"https://lh6.googleusercontent.com/-lEQE4h6TePE/URqu6t_lSkI/AAAAAAAAAbs/zvGYKOea_qY/s240-c/Over%252520there.jpg",
"https://lh5.googleusercontent.com/-cauH-53JH2M/URqu66v_USI/AAAAAAAAAbs/EucwwqclfKQ/s240-c/Plumes.jpg",
"https://lh3.googleusercontent.com/-eDLT2jHDoy4/URqu7axzkAI/AAAAAAAAAbs/iVZE-xJ7lZs/s240-c/Rainbokeh.jpg",
"https://lh5.googleusercontent.com/-j1NLqEFIyco/URqu8L1CGcI/AAAAAAAAAbs/aqZkgX66zlI/s240-c/Rainbow.jpg",
"https://lh5.googleusercontent.com/-DRnqmK0t4VU/URqu8XYN9yI/AAAAAAAAAbs/LgvF_592WLU/s240-c/Rice%252520Fields.jpg",
"https://lh3.googleusercontent.com/-hwh1v3EOGcQ/URqu8qOaKwI/AAAAAAAAAbs/IljRJRnbJGw/s240-c/Rockaway%252520Fire%252520Sky.jpg",
"https://lh5.googleusercontent.com/-wjV6FQk7tlk/URqu9jCQ8sI/AAAAAAAAAbs/RyYUpdo-c9o/s240-c/Rockaway%252520Flow.jpg",
"https://lh6.googleusercontent.com/-6cAXNfo7D20/URqu-BdzgPI/AAAAAAAAAbs/OmsYllzJqwo/s240-c/Rockaway%252520Sunset%252520Sky.jpg",
"https://lh3.googleusercontent.com/-sl8fpGPS-RE/URqu_BOkfgI/AAAAAAAAAbs/Dg2Fv-JxOeg/s240-c/Russian%252520Ridge%252520Sunset.jpg",
"https://lh6.googleusercontent.com/-gVtY36mMBIg/URqu_q91lkI/AAAAAAAAAbs/3CiFMBcy5MA/s240-c/Rust%252520Knot.jpg",
"https://lh6.googleusercontent.com/-GHeImuHqJBE/URqu_FKfVLI/AAAAAAAAAbs/axuEJeqam7Q/s240-c/Sailing%252520Stones.jpg",
"https://lh3.googleusercontent.com/-hBbYZjTOwGc/URqu_ycpIrI/AAAAAAAAAbs/nAdJUXnGJYE/s240-c/Seahorse.jpg",
"https://lh3.googleusercontent.com/-Iwi6-i6IexY/URqvAYZHsVI/AAAAAAAAAbs/5ETWl4qXsFE/s240-c/Shinjuku%252520Street.jpg",
"https://lh6.googleusercontent.com/-amhnySTM_MY/URqvAlb5KoI/AAAAAAAAAbs/pFCFgzlKsn0/s240-c/Sierra%252520Heavens.jpg",
"https://lh5.googleusercontent.com/-dJgjepFrYSo/URqvBVJZrAI/AAAAAAAAAbs/v-F5QWpYO6s/s240-c/Sierra%252520Sunset.jpg",
"https://lh4.googleusercontent.com/-Z4zGiC5nWdc/URqvBdEwivI/AAAAAAAAAbs/ZRZR1VJ84QA/s240-c/Sin%252520Lights.jpg",
"https://lh4.googleusercontent.com/-_0cYiWW8ccY/URqvBz3iM4I/AAAAAAAAAbs/9N_Wq8MhLTY/s240-c/Starry%252520Lake.jpg",
"https://lh3.googleusercontent.com/-A9LMoRyuQUA/URqvCYx_JoI/AAAAAAAAAbs/s7sde1Bz9cI/s240-c/Starry%252520Night.jpg",
"https://lh3.googleusercontent.com/-KtLJ3k858eY/URqvC_2h_bI/AAAAAAAAAbs/zzEBImwDA_g/s240-c/Stream.jpg",
"https://lh5.googleusercontent.com/-dFB7Lad6RcA/URqvDUftwWI/AAAAAAAAAbs/BrhoUtXTN7o/s240-c/Strip%252520Sunset.jpg",
"https://lh5.googleusercontent.com/-at6apgFiN20/URqvDyffUZI/AAAAAAAAAbs/clABCx171bE/s240-c/Sunset%252520Hills.jpg",
"https://lh4.googleusercontent.com/-7-EHhtQthII/URqvEYTk4vI/AAAAAAAAAbs/QSJZoB3YjVg/s240-c/Tenaya%252520Lake%2525202.jpg",
"https://lh6.googleusercontent.com/-8MrjV_a-Pok/URqvFC5repI/AAAAAAAAAbs/9inKTg9fbCE/s240-c/Tenaya%252520Lake.jpg",
"https://lh5.googleusercontent.com/-B1HW-z4zwao/URqvFWYRwUI/AAAAAAAAAbs/8Peli53Bs8I/s240-c/The%252520Cave%252520BW.jpg",
"https://lh3.googleusercontent.com/-PO4E-xZKAnQ/URqvGRqjYkI/AAAAAAAAAbs/42nyADFsXag/s240-c/The%252520Fisherman.jpg",
"https://lh4.googleusercontent.com/-iLyZlzfdy7s/URqvG0YScdI/AAAAAAAAAbs/1J9eDKmkXtk/s240-c/The%252520Night%252520is%252520Coming.jpg",
"https://lh6.googleusercontent.com/-G-k7YkkUco0/URqvHhah6fI/AAAAAAAAAbs/_taQQG7t0vo/s240-c/The%252520Road.jpg",
"https://lh6.googleusercontent.com/-h-ALJt7kSus/URqvIThqYfI/AAAAAAAAAbs/ejiv35olWS8/s240-c/Tokyo%252520Heights.jpg",
"https://lh5.googleusercontent.com/-Hy9k-TbS7xg/URqvIjQMOxI/AAAAAAAAAbs/RSpmmOATSkg/s240-c/Tokyo%252520Highway.jpg",
"https://lh6.googleusercontent.com/-83oOvMb4OZs/URqvJL0T7lI/AAAAAAAAAbs/c5TECZ6RONM/s240-c/Tokyo%252520Smog.jpg",
"https://lh3.googleusercontent.com/-FB-jfgREEfI/URqvJI3EXAI/AAAAAAAAAbs/XfyweiRF4v8/s240-c/Tufa%252520at%252520Night.jpg",
"https://lh4.googleusercontent.com/-vngKD5Z1U8w/URqvJUCEgPI/AAAAAAAAAbs/ulxCMVcU6EU/s240-c/Valley%252520Sunset.jpg",
"https://lh6.googleusercontent.com/-DOz5I2E2oMQ/URqvKMND1kI/AAAAAAAAAbs/Iqf0IsInleo/s240-c/Windmill%252520Sunrise.jpg",
"https://lh5.googleusercontent.com/-biyiyWcJ9MU/URqvKculiAI/AAAAAAAAAbs/jyPsCplJOpE/s240-c/Windmill.jpg",
"https://lh4.googleusercontent.com/-PDT167_xRdA/URqvK36mLcI/AAAAAAAAAbs/oi2ik9QseMI/s240-c/Windmills.jpg",
"https://lh5.googleusercontent.com/-kI_QdYx7VlU/URqvLXCB6gI/AAAAAAAAAbs/N31vlZ6u89o/s240-c/Yet%252520Another%252520Rockaway%252520Sunset.jpg",
"https://lh4.googleusercontent.com/-e9NHZ5k5MSs/URqvMIBZjtI/AAAAAAAAAbs/1fV810rDNfQ/s240-c/Yosemite%252520Tree.jpg",
};
}

213
samples/browseable/DisplayingBitmaps/src/com.example.android.displayingbitmaps/ui/ImageDetailActivity.java Normal file
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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.ui;
import android.annotation.TargetApi;
import android.app.ActionBar;
import android.os.Build.VERSION_CODES;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentStatePagerAdapter;
import android.support.v4.app.NavUtils;
import android.support.v4.view.ViewPager;
import android.util.DisplayMetrics;
import android.view.Menu;
import android.view.MenuItem;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.WindowManager.LayoutParams;
import android.widget.Toast;
import com.example.android.displayingbitmaps.BuildConfig;
import com.example.android.displayingbitmaps.R;
import com.example.android.displayingbitmaps.provider.Images;
import com.example.android.displayingbitmaps.util.ImageCache;
import com.example.android.displayingbitmaps.util.ImageFetcher;
import com.example.android.displayingbitmaps.util.Utils;
public class ImageDetailActivity extends FragmentActivity implements OnClickListener {
private static final String IMAGE_CACHE_DIR = "images";
public static final String EXTRA_IMAGE = "extra_image";
private ImagePagerAdapter mAdapter;
private ImageFetcher mImageFetcher;
private ViewPager mPager;
@TargetApi(VERSION_CODES.HONEYCOMB)
@Override
public void onCreate(Bundle savedInstanceState) {
if (BuildConfig.DEBUG) {
Utils.enableStrictMode();
}
super.onCreate(savedInstanceState);
setContentView(R.layout.image_detail_pager);
// Fetch screen height and width, to use as our max size when loading images as this
// activity runs full screen
final DisplayMetrics displayMetrics = new DisplayMetrics();
getWindowManager().getDefaultDisplay().getMetrics(displayMetrics);
final int height = displayMetrics.heightPixels;
final int width = displayMetrics.widthPixels;
// For this sample we'll use half of the longest width to resize our images. As the
// image scaling ensures the image is larger than this, we should be left with a
// resolution that is appropriate for both portrait and landscape. For best image quality
// we shouldn't divide by 2, but this will use more memory and require a larger memory
// cache.
final int longest = (height > width ? height : width) / 2;
ImageCache.ImageCacheParams cacheParams =
new ImageCache.ImageCacheParams(this, IMAGE_CACHE_DIR);
cacheParams.setMemCacheSizePercent(0.25f); // Set memory cache to 25% of app memory
// The ImageFetcher takes care of loading images into our ImageView children asynchronously
mImageFetcher = new ImageFetcher(this, longest);
mImageFetcher.addImageCache(getSupportFragmentManager(), cacheParams);
mImageFetcher.setImageFadeIn(false);
// Set up ViewPager and backing adapter
mAdapter = new ImagePagerAdapter(getSupportFragmentManager(), Images.imageUrls.length);
mPager = (ViewPager) findViewById(R.id.pager);
mPager.setAdapter(mAdapter);
mPager.setPageMargin((int) getResources().getDimension(R.dimen.horizontal_page_margin));
mPager.setOffscreenPageLimit(2);
// Set up activity to go full screen
getWindow().addFlags(LayoutParams.FLAG_FULLSCREEN);
// Enable some additional newer visibility and ActionBar features to create a more
// immersive photo viewing experience
if (Utils.hasHoneycomb()) {
final ActionBar actionBar = getActionBar();
// Hide title text and set home as up
actionBar.setDisplayShowTitleEnabled(false);
actionBar.setDisplayHomeAsUpEnabled(true);
// Hide and show the ActionBar as the visibility changes
mPager.setOnSystemUiVisibilityChangeListener(
new View.OnSystemUiVisibilityChangeListener() {
@Override
public void onSystemUiVisibilityChange(int vis) {
if ((vis & View.SYSTEM_UI_FLAG_LOW_PROFILE) != 0) {
actionBar.hide();
} else {
actionBar.show();
}
}
});
// Start low profile mode and hide ActionBar
mPager.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LOW_PROFILE);
actionBar.hide();
}
// Set the current item based on the extra passed in to this activity
final int extraCurrentItem = getIntent().getIntExtra(EXTRA_IMAGE, -1);
if (extraCurrentItem != -1) {
mPager.setCurrentItem(extraCurrentItem);
}
}
@Override
public void onResume() {
super.onResume();
mImageFetcher.setExitTasksEarly(false);
}
@Override
protected void onPause() {
super.onPause();
mImageFetcher.setExitTasksEarly(true);
mImageFetcher.flushCache();
}
@Override
protected void onDestroy() {
super.onDestroy();
mImageFetcher.closeCache();
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case android.R.id.home:
NavUtils.navigateUpFromSameTask(this);
return true;
case R.id.clear_cache:
mImageFetcher.clearCache();
Toast.makeText(
this, R.string.clear_cache_complete_toast,Toast.LENGTH_SHORT).show();
return true;
}
return super.onOptionsItemSelected(item);
}
@Override
public boolean onCreateOptionsMenu(Menu menu) {
getMenuInflater().inflate(R.menu.main_menu, menu);
return true;
}
/**
* Called by the ViewPager child fragments to load images via the one ImageFetcher
*/
public ImageFetcher getImageFetcher() {
return mImageFetcher;
}
/**
* The main adapter that backs the ViewPager. A subclass of FragmentStatePagerAdapter as there
* could be a large number of items in the ViewPager and we don't want to retain them all in
* memory at once but create/destroy them on the fly.
*/
private class ImagePagerAdapter extends FragmentStatePagerAdapter {
private final int mSize;
public ImagePagerAdapter(FragmentManager fm, int size) {
super(fm);
mSize = size;
}
@Override
public int getCount() {
return mSize;
}
@Override
public Fragment getItem(int position) {
return ImageDetailFragment.newInstance(Images.imageUrls[position]);
}
}
/**
* Set on the ImageView in the ViewPager children fragments, to enable/disable low profile mode
* when the ImageView is touched.
*/
@TargetApi(VERSION_CODES.HONEYCOMB)
@Override
public void onClick(View v) {
final int vis = mPager.getSystemUiVisibility();
if ((vis & View.SYSTEM_UI_FLAG_LOW_PROFILE) != 0) {
mPager.setSystemUiVisibility(View.SYSTEM_UI_FLAG_VISIBLE);
} else {
mPager.setSystemUiVisibility(View.SYSTEM_UI_FLAG_LOW_PROFILE);
}
}
}

107
samples/browseable/DisplayingBitmaps/src/com.example.android.displayingbitmaps/ui/ImageDetailFragment.java Normal file
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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.ui;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.view.LayoutInflater;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.ViewGroup;
import android.widget.ImageView;
import com.example.android.displayingbitmaps.R;
import com.example.android.displayingbitmaps.util.ImageFetcher;
import com.example.android.displayingbitmaps.util.ImageWorker;
import com.example.android.displayingbitmaps.util.Utils;
/**
* This fragment will populate the children of the ViewPager from {@link ImageDetailActivity}.
*/
public class ImageDetailFragment extends Fragment {
private static final String IMAGE_DATA_EXTRA = "extra_image_data";
private String mImageUrl;
private ImageView mImageView;
private ImageFetcher mImageFetcher;
/**
* Factory method to generate a new instance of the fragment given an image number.
*
* @param imageUrl The image url to load
* @return A new instance of ImageDetailFragment with imageNum extras
*/
public static ImageDetailFragment newInstance(String imageUrl) {
final ImageDetailFragment f = new ImageDetailFragment();
final Bundle args = new Bundle();
args.putString(IMAGE_DATA_EXTRA, imageUrl);
f.setArguments(args);
return f;
}
/**
* Empty constructor as per the Fragment documentation
*/
public ImageDetailFragment() {}
/**
* Populate image using a url from extras, use the convenience factory method
* {@link ImageDetailFragment#newInstance(String)} to create this fragment.
*/
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
mImageUrl = getArguments() != null ? getArguments().getString(IMAGE_DATA_EXTRA) : null;
}
@Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Inflate and locate the main ImageView
final View v = inflater.inflate(R.layout.image_detail_fragment, container, false);
mImageView = (ImageView) v.findViewById(R.id.imageView);
return v;
}
@Override
public void onActivityCreated(Bundle savedInstanceState) {
super.onActivityCreated(savedInstanceState);
// Use the parent activity to load the image asynchronously into the ImageView (so a single
// cache can be used over all pages in the ViewPager
if (ImageDetailActivity.class.isInstance(getActivity())) {
mImageFetcher = ((ImageDetailActivity) getActivity()).getImageFetcher();
mImageFetcher.loadImage(mImageUrl, mImageView);
}
// Pass clicks on the ImageView to the parent activity to handle
if (OnClickListener.class.isInstance(getActivity()) && Utils.hasHoneycomb()) {
mImageView.setOnClickListener((OnClickListener) getActivity());
}
}
@Override
public void onDestroy() {
super.onDestroy();
if (mImageView != null) {
// Cancel any pending image work
ImageWorker.cancelWork(mImageView);
mImageView.setImageDrawable(null);
}
}
}

45
samples/browseable/DisplayingBitmaps/src/com.example.android.displayingbitmaps/ui/ImageGridActivity.java Normal file
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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.ui;
import android.os.Bundle;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentTransaction;
import com.example.android.displayingbitmaps.BuildConfig;
import com.example.android.displayingbitmaps.util.Utils;
/**
* Simple FragmentActivity to hold the main {@link ImageGridFragment} and not much else.
*/
public class ImageGridActivity extends FragmentActivity {
private static final String TAG = "ImageGridActivity";
@Override
protected void onCreate(Bundle savedInstanceState) {
if (BuildConfig.DEBUG) {
Utils.enableStrictMode();
}
super.onCreate(savedInstanceState);
if (getSupportFragmentManager().findFragmentByTag(TAG) == null) {
final FragmentTransaction ft = getSupportFragmentManager().beginTransaction();
ft.add(android.R.id.content, new ImageGridFragment(), TAG);
ft.commit();
}
}
}

336
samples/browseable/DisplayingBitmaps/src/com.example.android.displayingbitmaps/ui/ImageGridFragment.java Normal file
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@@ -0,0 +1,336 @@
/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.ui;
import android.annotation.TargetApi;
import android.app.ActivityOptions;
import android.content.Context;
import android.content.Intent;
import android.os.Build.VERSION_CODES;
import android.os.Bundle;
import android.support.v4.app.Fragment;
import android.util.TypedValue;
import android.view.LayoutInflater;
import android.view.Menu;
import android.view.MenuInflater;
import android.view.MenuItem;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewGroup.LayoutParams;
import android.view.ViewTreeObserver;
import android.widget.AbsListView;
import android.widget.AdapterView;
import android.widget.BaseAdapter;
import android.widget.GridView;
import android.widget.ImageView;
import android.widget.Toast;
import com.example.android.common.logger.Log;
import com.example.android.displayingbitmaps.BuildConfig;
import com.example.android.displayingbitmaps.R;
import com.example.android.displayingbitmaps.provider.Images;
import com.example.android.displayingbitmaps.util.ImageCache;
import com.example.android.displayingbitmaps.util.ImageFetcher;
import com.example.android.displayingbitmaps.util.Utils;
/**
* The main fragment that powers the ImageGridActivity screen. Fairly straight forward GridView
* implementation with the key addition being the ImageWorker class w/ImageCache to load children
* asynchronously, keeping the UI nice and smooth and caching thumbnails for quick retrieval. The
* cache is retained over configuration changes like orientation change so the images are populated
* quickly if, for example, the user rotates the device.
*/
public class ImageGridFragment extends Fragment implements AdapterView.OnItemClickListener {
private static final String TAG = "ImageGridFragment";
private static final String IMAGE_CACHE_DIR = "thumbs";
private int mImageThumbSize;
private int mImageThumbSpacing;
private ImageAdapter mAdapter;
private ImageFetcher mImageFetcher;
/**
* Empty constructor as per the Fragment documentation
*/
public ImageGridFragment() {}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setHasOptionsMenu(true);
mImageThumbSize = getResources().getDimensionPixelSize(R.dimen.image_thumbnail_size);
mImageThumbSpacing = getResources().getDimensionPixelSize(R.dimen.image_thumbnail_spacing);
mAdapter = new ImageAdapter(getActivity());
ImageCache.ImageCacheParams cacheParams =
new ImageCache.ImageCacheParams(getActivity(), IMAGE_CACHE_DIR);
cacheParams.setMemCacheSizePercent(0.25f); // Set memory cache to 25% of app memory
// The ImageFetcher takes care of loading images into our ImageView children asynchronously
mImageFetcher = new ImageFetcher(getActivity(), mImageThumbSize);
mImageFetcher.setLoadingImage(R.drawable.empty_photo);
mImageFetcher.addImageCache(getActivity().getSupportFragmentManager(), cacheParams);
}
@Override
public View onCreateView(
LayoutInflater inflater, ViewGroup container, Bundle savedInstanceState) {
final View v = inflater.inflate(R.layout.image_grid_fragment, container, false);
final GridView mGridView = (GridView) v.findViewById(R.id.gridView);
mGridView.setAdapter(mAdapter);
mGridView.setOnItemClickListener(this);
mGridView.setOnScrollListener(new AbsListView.OnScrollListener() {
@Override
public void onScrollStateChanged(AbsListView absListView, int scrollState) {
// Pause fetcher to ensure smoother scrolling when flinging
if (scrollState == AbsListView.OnScrollListener.SCROLL_STATE_FLING) {
// Before Honeycomb pause image loading on scroll to help with performance
if (!Utils.hasHoneycomb()) {
mImageFetcher.setPauseWork(true);
}
} else {
mImageFetcher.setPauseWork(false);
}
}
@Override
public void onScroll(AbsListView absListView, int firstVisibleItem,
int visibleItemCount, int totalItemCount) {
}
});
// This listener is used to get the final width of the GridView and then calculate the
// number of columns and the width of each column. The width of each column is variable
// as the GridView has stretchMode=columnWidth. The column width is used to set the height
// of each view so we get nice square thumbnails.
mGridView.getViewTreeObserver().addOnGlobalLayoutListener(
new ViewTreeObserver.OnGlobalLayoutListener() {
@TargetApi(VERSION_CODES.JELLY_BEAN)
@Override
public void onGlobalLayout() {
if (mAdapter.getNumColumns() == 0) {
final int numColumns = (int) Math.floor(
mGridView.getWidth() / (mImageThumbSize + mImageThumbSpacing));
if (numColumns > 0) {
final int columnWidth =
(mGridView.getWidth() / numColumns) - mImageThumbSpacing;
mAdapter.setNumColumns(numColumns);
mAdapter.setItemHeight(columnWidth);
if (BuildConfig.DEBUG) {
Log.d(TAG, "onCreateView - numColumns set to " + numColumns);
}
if (Utils.hasJellyBean()) {
mGridView.getViewTreeObserver()
.removeOnGlobalLayoutListener(this);
} else {
mGridView.getViewTreeObserver()
.removeGlobalOnLayoutListener(this);
}
}
}
}
});
return v;
}
@Override
public void onResume() {
super.onResume();
mImageFetcher.setExitTasksEarly(false);
mAdapter.notifyDataSetChanged();
}
@Override
public void onPause() {
super.onPause();
mImageFetcher.setPauseWork(false);
mImageFetcher.setExitTasksEarly(true);
mImageFetcher.flushCache();
}
@Override
public void onDestroy() {
super.onDestroy();
mImageFetcher.closeCache();
}
@TargetApi(VERSION_CODES.JELLY_BEAN)
@Override
public void onItemClick(AdapterView<?> parent, View v, int position, long id) {
final Intent i = new Intent(getActivity(), ImageDetailActivity.class);
i.putExtra(ImageDetailActivity.EXTRA_IMAGE, (int) id);
if (Utils.hasJellyBean()) {
// makeThumbnailScaleUpAnimation() looks kind of ugly here as the loading spinner may
// show plus the thumbnail image in GridView is cropped. so using
// makeScaleUpAnimation() instead.
ActivityOptions options =
ActivityOptions.makeScaleUpAnimation(v, 0, 0, v.getWidth(), v.getHeight());
getActivity().startActivity(i, options.toBundle());
} else {
startActivity(i);
}
}
@Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.main_menu, menu);
}
@Override
public boolean onOptionsItemSelected(MenuItem item) {
switch (item.getItemId()) {
case R.id.clear_cache:
mImageFetcher.clearCache();
Toast.makeText(getActivity(), R.string.clear_cache_complete_toast,
Toast.LENGTH_SHORT).show();
return true;
}
return super.onOptionsItemSelected(item);
}
/**
* The main adapter that backs the GridView. This is fairly standard except the number of
* columns in the GridView is used to create a fake top row of empty views as we use a
* transparent ActionBar and don't want the real top row of images to start off covered by it.
*/
private class ImageAdapter extends BaseAdapter {
private final Context mContext;
private int mItemHeight = 0;
private int mNumColumns = 0;
private int mActionBarHeight = 0;
private GridView.LayoutParams mImageViewLayoutParams;
public ImageAdapter(Context context) {
super();
mContext = context;
mImageViewLayoutParams = new GridView.LayoutParams(
LayoutParams.MATCH_PARENT, LayoutParams.MATCH_PARENT);
// Calculate ActionBar height
TypedValue tv = new TypedValue();
if (context.getTheme().resolveAttribute(
android.R.attr.actionBarSize, tv, true)) {
mActionBarHeight = TypedValue.complexToDimensionPixelSize(
tv.data, context.getResources().getDisplayMetrics());
}
}
@Override
public int getCount() {
// If columns have yet to be determined, return no items
if (getNumColumns() == 0) {
return 0;
}
// Size + number of columns for top empty row
return Images.imageThumbUrls.length + mNumColumns;
}
@Override
public Object getItem(int position) {
return position < mNumColumns ?
null : Images.imageThumbUrls[position - mNumColumns];
}
@Override
public long getItemId(int position) {
return position < mNumColumns ? 0 : position - mNumColumns;
}
@Override
public int getViewTypeCount() {
// Two types of views, the normal ImageView and the top row of empty views
return 2;
}
@Override
public int getItemViewType(int position) {
return (position < mNumColumns) ? 1 : 0;
}
@Override
public boolean hasStableIds() {
return true;
}
@Override
public View getView(int position, View convertView, ViewGroup container) {
//BEGIN_INCLUDE(load_gridview_item)
// First check if this is the top row
if (position < mNumColumns) {
if (convertView == null) {
convertView = new View(mContext);
}
// Set empty view with height of ActionBar
convertView.setLayoutParams(new AbsListView.LayoutParams(
LayoutParams.MATCH_PARENT, mActionBarHeight));
return convertView;
}
// Now handle the main ImageView thumbnails
ImageView imageView;
if (convertView == null) { // if it's not recycled, instantiate and initialize
imageView = new RecyclingImageView(mContext);
imageView.setScaleType(ImageView.ScaleType.CENTER_CROP);
imageView.setLayoutParams(mImageViewLayoutParams);
} else { // Otherwise re-use the converted view
imageView = (ImageView) convertView;
}
// Check the height matches our calculated column width
if (imageView.getLayoutParams().height != mItemHeight) {
imageView.setLayoutParams(mImageViewLayoutParams);
}
// Finally load the image asynchronously into the ImageView, this also takes care of
// setting a placeholder image while the background thread runs
mImageFetcher.loadImage(Images.imageThumbUrls[position - mNumColumns], imageView);
return imageView;
//END_INCLUDE(load_gridview_item)
}
/**
* Sets the item height. Useful for when we know the column width so the height can be set
* to match.
*
* @param height
*/
public void setItemHeight(int height) {
if (height == mItemHeight) {
return;
}
mItemHeight = height;
mImageViewLayoutParams =
new GridView.LayoutParams(LayoutParams.MATCH_PARENT, mItemHeight);
mImageFetcher.setImageSize(height);
notifyDataSetChanged();
}
public void setNumColumns(int numColumns) {
mNumColumns = numColumns;
}
public int getNumColumns() {
return mNumColumns;
}
}
}

89
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/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.ui;
import android.content.Context;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.LayerDrawable;
import android.util.AttributeSet;
import android.widget.ImageView;
import com.example.android.displayingbitmaps.util.RecyclingBitmapDrawable;
/**
* Sub-class of ImageView which automatically notifies the drawable when it is
* being displayed.
*/
public class RecyclingImageView extends ImageView {
public RecyclingImageView(Context context) {
super(context);
}
public RecyclingImageView(Context context, AttributeSet attrs) {
super(context, attrs);
}
/**
* @see android.widget.ImageView#onDetachedFromWindow()
*/
@Override
protected void onDetachedFromWindow() {
// This has been detached from Window, so clear the drawable
setImageDrawable(null);
super.onDetachedFromWindow();
}
/**
* @see android.widget.ImageView#setImageDrawable(android.graphics.drawable.Drawable)
*/
@Override
public void setImageDrawable(Drawable drawable) {
// Keep hold of previous Drawable
final Drawable previousDrawable = getDrawable();
// Call super to set new Drawable
super.setImageDrawable(drawable);
// Notify new Drawable that it is being displayed
notifyDrawable(drawable, true);
// Notify old Drawable so it is no longer being displayed
notifyDrawable(previousDrawable, false);
}
/**
* Notifies the drawable that it's displayed state has changed.
*
* @param drawable
* @param isDisplayed
*/
private static void notifyDrawable(Drawable drawable, final boolean isDisplayed) {
if (drawable instanceof RecyclingBitmapDrawable) {
// The drawable is a CountingBitmapDrawable, so notify it
((RecyclingBitmapDrawable) drawable).setIsDisplayed(isDisplayed);
} else if (drawable instanceof LayerDrawable) {
// The drawable is a LayerDrawable, so recurse on each layer
LayerDrawable layerDrawable = (LayerDrawable) drawable;
for (int i = 0, z = layerDrawable.getNumberOfLayers(); i < z; i++) {
notifyDrawable(layerDrawable.getDrawable(i), isDisplayed);
}
}
}
}

693
samples/browseable/DisplayingBitmaps/src/com.example.android.displayingbitmaps/util/AsyncTask.java Normal file
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/*
* Copyright (C) 2008 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import android.annotation.TargetApi;
import android.os.Handler;
import android.os.Message;
import android.os.Process;
import java.util.ArrayDeque;
import java.util.concurrent.BlockingQueue;
import java.util.concurrent.Callable;
import java.util.concurrent.CancellationException;
import java.util.concurrent.ExecutionException;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.util.concurrent.FutureTask;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadFactory;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
import java.util.concurrent.TimeoutException;
import java.util.concurrent.atomic.AtomicBoolean;
import java.util.concurrent.atomic.AtomicInteger;
/**
* *************************************
* Copied from JB release framework:
* https://android.googlesource.com/platform/frameworks/base/+/jb-release/core/java/android/os/AsyncTask.java
*
* so that threading behavior on all OS versions is the same and we can tweak behavior by using
* executeOnExecutor() if needed.
*
* There are 3 changes in this copy of AsyncTask:
* -pre-HC a single thread executor is used for serial operation
* (Executors.newSingleThreadExecutor) and is the default
* -the default THREAD_POOL_EXECUTOR was changed to use DiscardOldestPolicy
* -a new fixed thread pool called DUAL_THREAD_EXECUTOR was added
* *************************************
*
* <p>AsyncTask enables proper and easy use of the UI thread. This class allows to
* perform background operations and publish results on the UI thread without
* having to manipulate threads and/or handlers.</p>
*
* <p>AsyncTask is designed to be a helper class around {@link Thread} and {@link android.os.Handler}
* and does not constitute a generic threading framework. AsyncTasks should ideally be
* used for short operations (a few seconds at the most.) If you need to keep threads
* running for long periods of time, it is highly recommended you use the various APIs
* provided by the <code>java.util.concurrent</code> pacakge such as {@link java.util.concurrent.Executor},
* {@link java.util.concurrent.ThreadPoolExecutor} and {@link java.util.concurrent.FutureTask}.</p>
*
* <p>An asynchronous task is defined by a computation that runs on a background thread and
* whose result is published on the UI thread. An asynchronous task is defined by 3 generic
* types, called <code>Params</code>, <code>Progress</code> and <code>Result</code>,
* and 4 steps, called <code>onPreExecute</code>, <code>doInBackground</code>,
* <code>onProgressUpdate</code> and <code>onPostExecute</code>.</p>
*
* <div class="special reference">
* <h3>Developer Guides</h3>
* <p>For more information about using tasks and threads, read the
* <a href="{@docRoot}guide/topics/fundamentals/processes-and-threads.html">Processes and
* Threads</a> developer guide.</p>
* </div>
*
* <h2>Usage</h2>
* <p>AsyncTask must be subclassed to be used. The subclass will override at least
* one method ({@link #doInBackground}), and most often will override a
* second one ({@link #onPostExecute}.)</p>
*
* <p>Here is an example of subclassing:</p>
* <pre class="prettyprint">
* private class DownloadFilesTask extends AsyncTask&lt;URL, Integer, Long&gt; {
* protected Long doInBackground(URL... urls) {
* int count = urls.length;
* long totalSize = 0;
* for (int i = 0; i < count; i++) {
* totalSize += Downloader.downloadFile(urls[i]);
* publishProgress((int) ((i / (float) count) * 100));
* // Escape early if cancel() is called
* if (isCancelled()) break;
* }
* return totalSize;
* }
*
* protected void onProgressUpdate(Integer... progress) {
* setProgressPercent(progress[0]);
* }
*
* protected void onPostExecute(Long result) {
* showDialog("Downloaded " + result + " bytes");
* }
* }
* </pre>
*
* <p>Once created, a task is executed very simply:</p>
* <pre class="prettyprint">
* new DownloadFilesTask().execute(url1, url2, url3);
* </pre>
*
* <h2>AsyncTask's generic types</h2>
* <p>The three types used by an asynchronous task are the following:</p>
* <ol>
* <li><code>Params</code>, the type of the parameters sent to the task upon
* execution.</li>
* <li><code>Progress</code>, the type of the progress units published during
* the background computation.</li>
* <li><code>Result</code>, the type of the result of the background
* computation.</li>
* </ol>
* <p>Not all types are always used by an asynchronous task. To mark a type as unused,
* simply use the type {@link Void}:</p>
* <pre>
* private class MyTask extends AsyncTask&lt;Void, Void, Void&gt; { ... }
* </pre>
*
* <h2>The 4 steps</h2>
* <p>When an asynchronous task is executed, the task goes through 4 steps:</p>
* <ol>
* <li>{@link #onPreExecute()}, invoked on the UI thread immediately after the task
* is executed. This step is normally used to setup the task, for instance by
* showing a progress bar in the user interface.</li>
* <li>{@link #doInBackground}, invoked on the background thread
* immediately after {@link #onPreExecute()} finishes executing. This step is used
* to perform background computation that can take a long time. The parameters
* of the asynchronous task are passed to this step. The result of the computation must
* be returned by this step and will be passed back to the last step. This step
* can also use {@link #publishProgress} to publish one or more units
* of progress. These values are published on the UI thread, in the
* {@link #onProgressUpdate} step.</li>
* <li>{@link #onProgressUpdate}, invoked on the UI thread after a
* call to {@link #publishProgress}. The timing of the execution is
* undefined. This method is used to display any form of progress in the user
* interface while the background computation is still executing. For instance,
* it can be used to animate a progress bar or show logs in a text field.</li>
* <li>{@link #onPostExecute}, invoked on the UI thread after the background
* computation finishes. The result of the background computation is passed to
* this step as a parameter.</li>
* </ol>
*
* <h2>Cancelling a task</h2>
* <p>A task can be cancelled at any time by invoking {@link #cancel(boolean)}. Invoking
* this method will cause subsequent calls to {@link #isCancelled()} to return true.
* After invoking this method, {@link #onCancelled(Object)}, instead of
* {@link #onPostExecute(Object)} will be invoked after {@link #doInBackground(Object[])}
* returns. To ensure that a task is cancelled as quickly as possible, you should always
* check the return value of {@link #isCancelled()} periodically from
* {@link #doInBackground(Object[])}, if possible (inside a loop for instance.)</p>
*
* <h2>Threading rules</h2>
* <p>There are a few threading rules that must be followed for this class to
* work properly:</p>
* <ul>
* <li>The AsyncTask class must be loaded on the UI thread. This is done
* automatically as of {@link android.os.Build.VERSION_CODES#JELLY_BEAN}.</li>
* <li>The task instance must be created on the UI thread.</li>
* <li>{@link #execute} must be invoked on the UI thread.</li>
* <li>Do not call {@link #onPreExecute()}, {@link #onPostExecute},
* {@link #doInBackground}, {@link #onProgressUpdate} manually.</li>
* <li>The task can be executed only once (an exception will be thrown if
* a second execution is attempted.)</li>
* </ul>
*
* <h2>Memory observability</h2>
* <p>AsyncTask guarantees that all callback calls are synchronized in such a way that the following
* operations are safe without explicit synchronizations.</p>
* <ul>
* <li>Set member fields in the constructor or {@link #onPreExecute}, and refer to them
* in {@link #doInBackground}.
* <li>Set member fields in {@link #doInBackground}, and refer to them in
* {@link #onProgressUpdate} and {@link #onPostExecute}.
* </ul>
*
* <h2>Order of execution</h2>
* <p>When first introduced, AsyncTasks were executed serially on a single background
* thread. Starting with {@link android.os.Build.VERSION_CODES#DONUT}, this was changed
* to a pool of threads allowing multiple tasks to operate in parallel. Starting with
* {@link android.os.Build.VERSION_CODES#HONEYCOMB}, tasks are executed on a single
* thread to avoid common application errors caused by parallel execution.</p>
* <p>If you truly want parallel execution, you can invoke
* {@link #executeOnExecutor(java.util.concurrent.Executor, Object[])} with
* {@link #THREAD_POOL_EXECUTOR}.</p>
*/
public abstract class AsyncTask<Params, Progress, Result> {
private static final String LOG_TAG = "AsyncTask";
private static final int CORE_POOL_SIZE = 5;
private static final int MAXIMUM_POOL_SIZE = 128;
private static final int KEEP_ALIVE = 1;
private static final ThreadFactory sThreadFactory = new ThreadFactory() {
private final AtomicInteger mCount = new AtomicInteger(1);
public Thread newThread(Runnable r) {
return new Thread(r, "AsyncTask #" + mCount.getAndIncrement());
}
};
private static final BlockingQueue<Runnable> sPoolWorkQueue =
new LinkedBlockingQueue<Runnable>(10);
/**
* An {@link java.util.concurrent.Executor} that can be used to execute tasks in parallel.
*/
public static final Executor THREAD_POOL_EXECUTOR
= new ThreadPoolExecutor(CORE_POOL_SIZE, MAXIMUM_POOL_SIZE, KEEP_ALIVE,
TimeUnit.SECONDS, sPoolWorkQueue, sThreadFactory,
new ThreadPoolExecutor.DiscardOldestPolicy());
/**
* An {@link java.util.concurrent.Executor} that executes tasks one at a time in serial
* order. This serialization is global to a particular process.
*/
public static final Executor SERIAL_EXECUTOR = Utils.hasHoneycomb() ? new SerialExecutor() :
Executors.newSingleThreadExecutor(sThreadFactory);
public static final Executor DUAL_THREAD_EXECUTOR =
Executors.newFixedThreadPool(2, sThreadFactory);
private static final int MESSAGE_POST_RESULT = 0x1;
private static final int MESSAGE_POST_PROGRESS = 0x2;
private static final InternalHandler sHandler = new InternalHandler();
private static volatile Executor sDefaultExecutor = SERIAL_EXECUTOR;
private final WorkerRunnable<Params, Result> mWorker;
private final FutureTask<Result> mFuture;
private volatile Status mStatus = Status.PENDING;
private final AtomicBoolean mCancelled = new AtomicBoolean();
private final AtomicBoolean mTaskInvoked = new AtomicBoolean();
@TargetApi(11)
private static class SerialExecutor implements Executor {
final ArrayDeque<Runnable> mTasks = new ArrayDeque<Runnable>();
Runnable mActive;
public synchronized void execute(final Runnable r) {
mTasks.offer(new Runnable() {
public void run() {
try {
r.run();
} finally {
scheduleNext();
}
}
});
if (mActive == null) {
scheduleNext();
}
}
protected synchronized void scheduleNext() {
if ((mActive = mTasks.poll()) != null) {
THREAD_POOL_EXECUTOR.execute(mActive);
}
}
}
/**
* Indicates the current status of the task. Each status will be set only once
* during the lifetime of a task.
*/
public enum Status {
/**
* Indicates that the task has not been executed yet.
*/
PENDING,
/**
* Indicates that the task is running.
*/
RUNNING,
/**
* Indicates that {@link AsyncTask#onPostExecute} has finished.
*/
FINISHED,
}
/** @hide Used to force static handler to be created. */
public static void init() {
sHandler.getLooper();
}
/** @hide */
public static void setDefaultExecutor(Executor exec) {
sDefaultExecutor = exec;
}
/**
* Creates a new asynchronous task. This constructor must be invoked on the UI thread.
*/
public AsyncTask() {
mWorker = new WorkerRunnable<Params, Result>() {
public Result call() throws Exception {
mTaskInvoked.set(true);
Process.setThreadPriority(Process.THREAD_PRIORITY_BACKGROUND);
//noinspection unchecked
return postResult(doInBackground(mParams));
}
};
mFuture = new FutureTask<Result>(mWorker) {
@Override
protected void done() {
try {
postResultIfNotInvoked(get());
} catch (InterruptedException e) {
android.util.Log.w(LOG_TAG, e);
} catch (ExecutionException e) {
throw new RuntimeException("An error occured while executing doInBackground()",
e.getCause());
} catch (CancellationException e) {
postResultIfNotInvoked(null);
}
}
};
}
private void postResultIfNotInvoked(Result result) {
final boolean wasTaskInvoked = mTaskInvoked.get();
if (!wasTaskInvoked) {
postResult(result);
}
}
private Result postResult(Result result) {
@SuppressWarnings("unchecked")
Message message = sHandler.obtainMessage(MESSAGE_POST_RESULT,
new AsyncTaskResult<Result>(this, result));
message.sendToTarget();
return result;
}
/**
* Returns the current status of this task.
*
* @return The current status.
*/
public final Status getStatus() {
return mStatus;
}
/**
* Override this method to perform a computation on a background thread. The
* specified parameters are the parameters passed to {@link #execute}
* by the caller of this task.
*
* This method can call {@link #publishProgress} to publish updates
* on the UI thread.
*
* @param params The parameters of the task.
*
* @return A result, defined by the subclass of this task.
*
* @see #onPreExecute()
* @see #onPostExecute
* @see #publishProgress
*/
protected abstract Result doInBackground(Params... params);
/**
* Runs on the UI thread before {@link #doInBackground}.
*
* @see #onPostExecute
* @see #doInBackground
*/
protected void onPreExecute() {
}
/**
* <p>Runs on the UI thread after {@link #doInBackground}. The
* specified result is the value returned by {@link #doInBackground}.</p>
*
* <p>This method won't be invoked if the task was cancelled.</p>
*
* @param result The result of the operation computed by {@link #doInBackground}.
*
* @see #onPreExecute
* @see #doInBackground
* @see #onCancelled(Object)
*/
@SuppressWarnings({"UnusedDeclaration"})
protected void onPostExecute(Result result) {
}
/**
* Runs on the UI thread after {@link #publishProgress} is invoked.
* The specified values are the values passed to {@link #publishProgress}.
*
* @param values The values indicating progress.
*
* @see #publishProgress
* @see #doInBackground
*/
@SuppressWarnings({"UnusedDeclaration"})
protected void onProgressUpdate(Progress... values) {
}
/**
* <p>Runs on the UI thread after {@link #cancel(boolean)} is invoked and
* {@link #doInBackground(Object[])} has finished.</p>
*
* <p>The default implementation simply invokes {@link #onCancelled()} and
* ignores the result. If you write your own implementation, do not call
* <code>super.onCancelled(result)</code>.</p>
*
* @param result The result, if any, computed in
* {@link #doInBackground(Object[])}, can be null
*
* @see #cancel(boolean)
* @see #isCancelled()
*/
@SuppressWarnings({"UnusedParameters"})
protected void onCancelled(Result result) {
onCancelled();
}
/**
* <p>Applications should preferably override {@link #onCancelled(Object)}.
* This method is invoked by the default implementation of
* {@link #onCancelled(Object)}.</p>
*
* <p>Runs on the UI thread after {@link #cancel(boolean)} is invoked and
* {@link #doInBackground(Object[])} has finished.</p>
*
* @see #onCancelled(Object)
* @see #cancel(boolean)
* @see #isCancelled()
*/
protected void onCancelled() {
}
/**
* Returns <tt>true</tt> if this task was cancelled before it completed
* normally. If you are calling {@link #cancel(boolean)} on the task,
* the value returned by this method should be checked periodically from
* {@link #doInBackground(Object[])} to end the task as soon as possible.
*
* @return <tt>true</tt> if task was cancelled before it completed
*
* @see #cancel(boolean)
*/
public final boolean isCancelled() {
return mCancelled.get();
}
/**
* <p>Attempts to cancel execution of this task. This attempt will
* fail if the task has already completed, already been cancelled,
* or could not be cancelled for some other reason. If successful,
* and this task has not started when <tt>cancel</tt> is called,
* this task should never run. If the task has already started,
* then the <tt>mayInterruptIfRunning</tt> parameter determines
* whether the thread executing this task should be interrupted in
* an attempt to stop the task.</p>
*
* <p>Calling this method will result in {@link #onCancelled(Object)} being
* invoked on the UI thread after {@link #doInBackground(Object[])}
* returns. Calling this method guarantees that {@link #onPostExecute(Object)}
* is never invoked. After invoking this method, you should check the
* value returned by {@link #isCancelled()} periodically from
* {@link #doInBackground(Object[])} to finish the task as early as
* possible.</p>
*
* @param mayInterruptIfRunning <tt>true</tt> if the thread executing this
* task should be interrupted; otherwise, in-progress tasks are allowed
* to complete.
*
* @return <tt>false</tt> if the task could not be cancelled,
* typically because it has already completed normally;
* <tt>true</tt> otherwise
*
* @see #isCancelled()
* @see #onCancelled(Object)
*/
public final boolean cancel(boolean mayInterruptIfRunning) {
mCancelled.set(true);
return mFuture.cancel(mayInterruptIfRunning);
}
/**
* Waits if necessary for the computation to complete, and then
* retrieves its result.
*
* @return The computed result.
*
* @throws java.util.concurrent.CancellationException If the computation was cancelled.
* @throws java.util.concurrent.ExecutionException If the computation threw an exception.
* @throws InterruptedException If the current thread was interrupted
* while waiting.
*/
public final Result get() throws InterruptedException, ExecutionException {
return mFuture.get();
}
/**
* Waits if necessary for at most the given time for the computation
* to complete, and then retrieves its result.
*
* @param timeout Time to wait before cancelling the operation.
* @param unit The time unit for the timeout.
*
* @return The computed result.
*
* @throws java.util.concurrent.CancellationException If the computation was cancelled.
* @throws java.util.concurrent.ExecutionException If the computation threw an exception.
* @throws InterruptedException If the current thread was interrupted
* while waiting.
* @throws java.util.concurrent.TimeoutException If the wait timed out.
*/
public final Result get(long timeout, TimeUnit unit) throws InterruptedException,
ExecutionException, TimeoutException {
return mFuture.get(timeout, unit);
}
/**
* Executes the task with the specified parameters. The task returns
* itself (this) so that the caller can keep a reference to it.
*
* <p>Note: this function schedules the task on a queue for a single background
* thread or pool of threads depending on the platform version. When first
* introduced, AsyncTasks were executed serially on a single background thread.
* Starting with {@link android.os.Build.VERSION_CODES#DONUT}, this was changed
* to a pool of threads allowing multiple tasks to operate in parallel. Starting
* {@link android.os.Build.VERSION_CODES#HONEYCOMB}, tasks are back to being
* executed on a single thread to avoid common application errors caused
* by parallel execution. If you truly want parallel execution, you can use
* the {@link #executeOnExecutor} version of this method
* with {@link #THREAD_POOL_EXECUTOR}; however, see commentary there for warnings
* on its use.
*
* <p>This method must be invoked on the UI thread.
*
* @param params The parameters of the task.
*
* @return This instance of AsyncTask.
*
* @throws IllegalStateException If {@link #getStatus()} returns either
* {@link AsyncTask.Status#RUNNING} or {@link AsyncTask.Status#FINISHED}.
*
* @see #executeOnExecutor(java.util.concurrent.Executor, Object[])
* @see #execute(Runnable)
*/
public final AsyncTask<Params, Progress, Result> execute(Params... params) {
return executeOnExecutor(sDefaultExecutor, params);
}
/**
* Executes the task with the specified parameters. The task returns
* itself (this) so that the caller can keep a reference to it.
*
* <p>This method is typically used with {@link #THREAD_POOL_EXECUTOR} to
* allow multiple tasks to run in parallel on a pool of threads managed by
* AsyncTask, however you can also use your own {@link java.util.concurrent.Executor} for custom
* behavior.
*
* <p><em>Warning:</em> Allowing multiple tasks to run in parallel from
* a thread pool is generally <em>not</em> what one wants, because the order
* of their operation is not defined. For example, if these tasks are used
* to modify any state in common (such as writing a file due to a button click),
* there are no guarantees on the order of the modifications.
* Without careful work it is possible in rare cases for the newer version
* of the data to be over-written by an older one, leading to obscure data
* loss and stability issues. Such changes are best
* executed in serial; to guarantee such work is serialized regardless of
* platform version you can use this function with {@link #SERIAL_EXECUTOR}.
*
* <p>This method must be invoked on the UI thread.
*
* @param exec The executor to use. {@link #THREAD_POOL_EXECUTOR} is available as a
* convenient process-wide thread pool for tasks that are loosely coupled.
* @param params The parameters of the task.
*
* @return This instance of AsyncTask.
*
* @throws IllegalStateException If {@link #getStatus()} returns either
* {@link AsyncTask.Status#RUNNING} or {@link AsyncTask.Status#FINISHED}.
*
* @see #execute(Object[])
*/
public final AsyncTask<Params, Progress, Result> executeOnExecutor(Executor exec,
Params... params) {
if (mStatus != Status.PENDING) {
switch (mStatus) {
case RUNNING:
throw new IllegalStateException("Cannot execute task:"
+ " the task is already running.");
case FINISHED:
throw new IllegalStateException("Cannot execute task:"
+ " the task has already been executed "
+ "(a task can be executed only once)");
}
}
mStatus = Status.RUNNING;
onPreExecute();
mWorker.mParams = params;
exec.execute(mFuture);
return this;
}
/**
* Convenience version of {@link #execute(Object...)} for use with
* a simple Runnable object. See {@link #execute(Object[])} for more
* information on the order of execution.
*
* @see #execute(Object[])
* @see #executeOnExecutor(java.util.concurrent.Executor, Object[])
*/
public static void execute(Runnable runnable) {
sDefaultExecutor.execute(runnable);
}
/**
* This method can be invoked from {@link #doInBackground} to
* publish updates on the UI thread while the background computation is
* still running. Each call to this method will trigger the execution of
* {@link #onProgressUpdate} on the UI thread.
*
* {@link #onProgressUpdate} will note be called if the task has been
* canceled.
*
* @param values The progress values to update the UI with.
*
* @see #onProgressUpdate
* @see #doInBackground
*/
protected final void publishProgress(Progress... values) {
if (!isCancelled()) {
sHandler.obtainMessage(MESSAGE_POST_PROGRESS,
new AsyncTaskResult<Progress>(this, values)).sendToTarget();
}
}
private void finish(Result result) {
if (isCancelled()) {
onCancelled(result);
} else {
onPostExecute(result);
}
mStatus = Status.FINISHED;
}
private static class InternalHandler extends Handler {
@SuppressWarnings({"unchecked", "RawUseOfParameterizedType"})
@Override
public void handleMessage(Message msg) {
AsyncTaskResult result = (AsyncTaskResult) msg.obj;
switch (msg.what) {
case MESSAGE_POST_RESULT:
// There is only one result
result.mTask.finish(result.mData[0]);
break;
case MESSAGE_POST_PROGRESS:
result.mTask.onProgressUpdate(result.mData);
break;
}
}
}
private static abstract class WorkerRunnable<Params, Result> implements Callable<Result> {
Params[] mParams;
}
@SuppressWarnings({"RawUseOfParameterizedType"})
private static class AsyncTaskResult<Data> {
final AsyncTask mTask;
final Data[] mData;
AsyncTaskResult(AsyncTask task, Data... data) {
mTask = task;
mData = data;
}
}
}

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@@ -0,0 +1,953 @@
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import java.io.BufferedInputStream;
import java.io.BufferedWriter;
import java.io.Closeable;
import java.io.EOFException;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.FilterOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.StringWriter;
import java.io.Writer;
import java.lang.reflect.Array;
import java.nio.charset.Charset;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Iterator;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.concurrent.Callable;
import java.util.concurrent.ExecutorService;
import java.util.concurrent.LinkedBlockingQueue;
import java.util.concurrent.ThreadPoolExecutor;
import java.util.concurrent.TimeUnit;
/**
******************************************************************************
* Taken from the JB source code, can be found in:
* libcore/luni/src/main/java/libcore/io/DiskLruCache.java
* or direct link:
* https://android.googlesource.com/platform/libcore/+/android-4.1.1_r1/luni/src/main/java/libcore/io/DiskLruCache.java
******************************************************************************
*
* A cache that uses a bounded amount of space on a filesystem. Each cache
* entry has a string key and a fixed number of values. Values are byte
* sequences, accessible as streams or files. Each value must be between {@code
* 0} and {@code Integer.MAX_VALUE} bytes in length.
*
* <p>The cache stores its data in a directory on the filesystem. This
* directory must be exclusive to the cache; the cache may delete or overwrite
* files from its directory. It is an error for multiple processes to use the
* same cache directory at the same time.
*
* <p>This cache limits the number of bytes that it will store on the
* filesystem. When the number of stored bytes exceeds the limit, the cache will
* remove entries in the background until the limit is satisfied. The limit is
* not strict: the cache may temporarily exceed it while waiting for files to be
* deleted. The limit does not include filesystem overhead or the cache
* journal so space-sensitive applications should set a conservative limit.
*
* <p>Clients call {@link #edit} to create or update the values of an entry. An
* entry may have only one editor at one time; if a value is not available to be
* edited then {@link #edit} will return null.
* <ul>
* <li>When an entry is being <strong>created</strong> it is necessary to
* supply a full set of values; the empty value should be used as a
* placeholder if necessary.
* <li>When an entry is being <strong>edited</strong>, it is not necessary
* to supply data for every value; values default to their previous
* value.
* </ul>
* Every {@link #edit} call must be matched by a call to {@link Editor#commit}
* or {@link Editor#abort}. Committing is atomic: a read observes the full set
* of values as they were before or after the commit, but never a mix of values.
*
* <p>Clients call {@link #get} to read a snapshot of an entry. The read will
* observe the value at the time that {@link #get} was called. Updates and
* removals after the call do not impact ongoing reads.
*
* <p>This class is tolerant of some I/O errors. If files are missing from the
* filesystem, the corresponding entries will be dropped from the cache. If
* an error occurs while writing a cache value, the edit will fail silently.
* Callers should handle other problems by catching {@code IOException} and
* responding appropriately.
*/
public final class DiskLruCache implements Closeable {
static final String JOURNAL_FILE = "journal";
static final String JOURNAL_FILE_TMP = "journal.tmp";
static final String MAGIC = "libcore.io.DiskLruCache";
static final String VERSION_1 = "1";
static final long ANY_SEQUENCE_NUMBER = -1;
private static final String CLEAN = "CLEAN";
private static final String DIRTY = "DIRTY";
private static final String REMOVE = "REMOVE";
private static final String READ = "READ";
private static final Charset UTF_8 = Charset.forName("UTF-8");
private static final int IO_BUFFER_SIZE = 8 * 1024;
/*
* This cache uses a journal file named "journal". A typical journal file
* looks like this:
* libcore.io.DiskLruCache
* 1
* 100
* 2
*
* CLEAN 3400330d1dfc7f3f7f4b8d4d803dfcf6 832 21054
* DIRTY 335c4c6028171cfddfbaae1a9c313c52
* CLEAN 335c4c6028171cfddfbaae1a9c313c52 3934 2342
* REMOVE 335c4c6028171cfddfbaae1a9c313c52
* DIRTY 1ab96a171faeeee38496d8b330771a7a
* CLEAN 1ab96a171faeeee38496d8b330771a7a 1600 234
* READ 335c4c6028171cfddfbaae1a9c313c52
* READ 3400330d1dfc7f3f7f4b8d4d803dfcf6
*
* The first five lines of the journal form its header. They are the
* constant string "libcore.io.DiskLruCache", the disk cache's version,
* the application's version, the value count, and a blank line.
*
* Each of the subsequent lines in the file is a record of the state of a
* cache entry. Each line contains space-separated values: a state, a key,
* and optional state-specific values.
* o DIRTY lines track that an entry is actively being created or updated.
* Every successful DIRTY action should be followed by a CLEAN or REMOVE
* action. DIRTY lines without a matching CLEAN or REMOVE indicate that
* temporary files may need to be deleted.
* o CLEAN lines track a cache entry that has been successfully published
* and may be read. A publish line is followed by the lengths of each of
* its values.
* o READ lines track accesses for LRU.
* o REMOVE lines track entries that have been deleted.
*
* The journal file is appended to as cache operations occur. The journal may
* occasionally be compacted by dropping redundant lines. A temporary file named
* "journal.tmp" will be used during compaction; that file should be deleted if
* it exists when the cache is opened.
*/
private final File directory;
private final File journalFile;
private final File journalFileTmp;
private final int appVersion;
private final long maxSize;
private final int valueCount;
private long size = 0;
private Writer journalWriter;
private final LinkedHashMap<String, Entry> lruEntries
= new LinkedHashMap<String, Entry>(0, 0.75f, true);
private int redundantOpCount;
/**
* To differentiate between old and current snapshots, each entry is given
* a sequence number each time an edit is committed. A snapshot is stale if
* its sequence number is not equal to its entry's sequence number.
*/
private long nextSequenceNumber = 0;
/* From java.util.Arrays */
@SuppressWarnings("unchecked")
private static <T> T[] copyOfRange(T[] original, int start, int end) {
final int originalLength = original.length; // For exception priority compatibility.
if (start > end) {
throw new IllegalArgumentException();
}
if (start < 0 || start > originalLength) {
throw new ArrayIndexOutOfBoundsException();
}
final int resultLength = end - start;
final int copyLength = Math.min(resultLength, originalLength - start);
final T[] result = (T[]) Array
.newInstance(original.getClass().getComponentType(), resultLength);
System.arraycopy(original, start, result, 0, copyLength);
return result;
}
/**
* Returns the remainder of 'reader' as a string, closing it when done.
*/
public static String readFully(Reader reader) throws IOException {
try {
StringWriter writer = new StringWriter();
char[] buffer = new char[1024];
int count;
while ((count = reader.read(buffer)) != -1) {
writer.write(buffer, 0, count);
}
return writer.toString();
} finally {
reader.close();
}
}
/**
* Returns the ASCII characters up to but not including the next "\r\n", or
* "\n".
*
* @throws java.io.EOFException if the stream is exhausted before the next newline
* character.
*/
public static String readAsciiLine(InputStream in) throws IOException {
// TODO: support UTF-8 here instead
StringBuilder result = new StringBuilder(80);
while (true) {
int c = in.read();
if (c == -1) {
throw new EOFException();
} else if (c == '\n') {
break;
}
result.append((char) c);
}
int length = result.length();
if (length > 0 && result.charAt(length - 1) == '\r') {
result.setLength(length - 1);
}
return result.toString();
}
/**
* Closes 'closeable', ignoring any checked exceptions. Does nothing if 'closeable' is null.
*/
public static void closeQuietly(Closeable closeable) {
if (closeable != null) {
try {
closeable.close();
} catch (RuntimeException rethrown) {
throw rethrown;
} catch (Exception ignored) {
}
}
}
/**
* Recursively delete everything in {@code dir}.
*/
// TODO: this should specify paths as Strings rather than as Files
public static void deleteContents(File dir) throws IOException {
File[] files = dir.listFiles();
if (files == null) {
throw new IllegalArgumentException("not a directory: " + dir);
}
for (File file : files) {
if (file.isDirectory()) {
deleteContents(file);
}
if (!file.delete()) {
throw new IOException("failed to delete file: " + file);
}
}
}
/** This cache uses a single background thread to evict entries. */
private final ExecutorService executorService = new ThreadPoolExecutor(0, 1,
60L, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>());
private final Callable<Void> cleanupCallable = new Callable<Void>() {
@Override public Void call() throws Exception {
synchronized (DiskLruCache.this) {
if (journalWriter == null) {
return null; // closed
}
trimToSize();
if (journalRebuildRequired()) {
rebuildJournal();
redundantOpCount = 0;
}
}
return null;
}
};
private DiskLruCache(File directory, int appVersion, int valueCount, long maxSize) {
this.directory = directory;
this.appVersion = appVersion;
this.journalFile = new File(directory, JOURNAL_FILE);
this.journalFileTmp = new File(directory, JOURNAL_FILE_TMP);
this.valueCount = valueCount;
this.maxSize = maxSize;
}
/**
* Opens the cache in {@code directory}, creating a cache if none exists
* there.
*
* @param directory a writable directory
* @param appVersion
* @param valueCount the number of values per cache entry. Must be positive.
* @param maxSize the maximum number of bytes this cache should use to store
* @throws java.io.IOException if reading or writing the cache directory fails
*/
public static DiskLruCache open(File directory, int appVersion, int valueCount, long maxSize)
throws IOException {
if (maxSize <= 0) {
throw new IllegalArgumentException("maxSize <= 0");
}
if (valueCount <= 0) {
throw new IllegalArgumentException("valueCount <= 0");
}
// prefer to pick up where we left off
DiskLruCache cache = new DiskLruCache(directory, appVersion, valueCount, maxSize);
if (cache.journalFile.exists()) {
try {
cache.readJournal();
cache.processJournal();
cache.journalWriter = new BufferedWriter(new FileWriter(cache.journalFile, true),
IO_BUFFER_SIZE);
return cache;
} catch (IOException journalIsCorrupt) {
// System.logW("DiskLruCache " + directory + " is corrupt: "
// + journalIsCorrupt.getMessage() + ", removing");
cache.delete();
}
}
// create a new empty cache
directory.mkdirs();
cache = new DiskLruCache(directory, appVersion, valueCount, maxSize);
cache.rebuildJournal();
return cache;
}
private void readJournal() throws IOException {
InputStream in = new BufferedInputStream(new FileInputStream(journalFile), IO_BUFFER_SIZE);
try {
String magic = readAsciiLine(in);
String version = readAsciiLine(in);
String appVersionString = readAsciiLine(in);
String valueCountString = readAsciiLine(in);
String blank = readAsciiLine(in);
if (!MAGIC.equals(magic)
|| !VERSION_1.equals(version)
|| !Integer.toString(appVersion).equals(appVersionString)
|| !Integer.toString(valueCount).equals(valueCountString)
|| !"".equals(blank)) {
throw new IOException("unexpected journal header: ["
+ magic + ", " + version + ", " + valueCountString + ", " + blank + "]");
}
while (true) {
try {
readJournalLine(readAsciiLine(in));
} catch (EOFException endOfJournal) {
break;
}
}
} finally {
closeQuietly(in);
}
}
private void readJournalLine(String line) throws IOException {
String[] parts = line.split(" ");
if (parts.length < 2) {
throw new IOException("unexpected journal line: " + line);
}
String key = parts[1];
if (parts[0].equals(REMOVE) && parts.length == 2) {
lruEntries.remove(key);
return;
}
Entry entry = lruEntries.get(key);
if (entry == null) {
entry = new Entry(key);
lruEntries.put(key, entry);
}
if (parts[0].equals(CLEAN) && parts.length == 2 + valueCount) {
entry.readable = true;
entry.currentEditor = null;
entry.setLengths(copyOfRange(parts, 2, parts.length));
} else if (parts[0].equals(DIRTY) && parts.length == 2) {
entry.currentEditor = new Editor(entry);
} else if (parts[0].equals(READ) && parts.length == 2) {
// this work was already done by calling lruEntries.get()
} else {
throw new IOException("unexpected journal line: " + line);
}
}
/**
* Computes the initial size and collects garbage as a part of opening the
* cache. Dirty entries are assumed to be inconsistent and will be deleted.
*/
private void processJournal() throws IOException {
deleteIfExists(journalFileTmp);
for (Iterator<Entry> i = lruEntries.values().iterator(); i.hasNext(); ) {
Entry entry = i.next();
if (entry.currentEditor == null) {
for (int t = 0; t < valueCount; t++) {
size += entry.lengths[t];
}
} else {
entry.currentEditor = null;
for (int t = 0; t < valueCount; t++) {
deleteIfExists(entry.getCleanFile(t));
deleteIfExists(entry.getDirtyFile(t));
}
i.remove();
}
}
}
/**
* Creates a new journal that omits redundant information. This replaces the
* current journal if it exists.
*/
private synchronized void rebuildJournal() throws IOException {
if (journalWriter != null) {
journalWriter.close();
}
Writer writer = new BufferedWriter(new FileWriter(journalFileTmp), IO_BUFFER_SIZE);
writer.write(MAGIC);
writer.write("\n");
writer.write(VERSION_1);
writer.write("\n");
writer.write(Integer.toString(appVersion));
writer.write("\n");
writer.write(Integer.toString(valueCount));
writer.write("\n");
writer.write("\n");
for (Entry entry : lruEntries.values()) {
if (entry.currentEditor != null) {
writer.write(DIRTY + ' ' + entry.key + '\n');
} else {
writer.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n');
}
}
writer.close();
journalFileTmp.renameTo(journalFile);
journalWriter = new BufferedWriter(new FileWriter(journalFile, true), IO_BUFFER_SIZE);
}
private static void deleteIfExists(File file) throws IOException {
// try {
// Libcore.os.remove(file.getPath());
// } catch (ErrnoException errnoException) {
// if (errnoException.errno != OsConstants.ENOENT) {
// throw errnoException.rethrowAsIOException();
// }
// }
if (file.exists() && !file.delete()) {
throw new IOException();
}
}
/**
* Returns a snapshot of the entry named {@code key}, or null if it doesn't
* exist is not currently readable. If a value is returned, it is moved to
* the head of the LRU queue.
*/
public synchronized Snapshot get(String key) throws IOException {
checkNotClosed();
validateKey(key);
Entry entry = lruEntries.get(key);
if (entry == null) {
return null;
}
if (!entry.readable) {
return null;
}
/*
* Open all streams eagerly to guarantee that we see a single published
* snapshot. If we opened streams lazily then the streams could come
* from different edits.
*/
InputStream[] ins = new InputStream[valueCount];
try {
for (int i = 0; i < valueCount; i++) {
ins[i] = new FileInputStream(entry.getCleanFile(i));
}
} catch (FileNotFoundException e) {
// a file must have been deleted manually!
return null;
}
redundantOpCount++;
journalWriter.append(READ + ' ' + key + '\n');
if (journalRebuildRequired()) {
executorService.submit(cleanupCallable);
}
return new Snapshot(key, entry.sequenceNumber, ins);
}
/**
* Returns an editor for the entry named {@code key}, or null if another
* edit is in progress.
*/
public Editor edit(String key) throws IOException {
return edit(key, ANY_SEQUENCE_NUMBER);
}
private synchronized Editor edit(String key, long expectedSequenceNumber) throws IOException {
checkNotClosed();
validateKey(key);
Entry entry = lruEntries.get(key);
if (expectedSequenceNumber != ANY_SEQUENCE_NUMBER
&& (entry == null || entry.sequenceNumber != expectedSequenceNumber)) {
return null; // snapshot is stale
}
if (entry == null) {
entry = new Entry(key);
lruEntries.put(key, entry);
} else if (entry.currentEditor != null) {
return null; // another edit is in progress
}
Editor editor = new Editor(entry);
entry.currentEditor = editor;
// flush the journal before creating files to prevent file leaks
journalWriter.write(DIRTY + ' ' + key + '\n');
journalWriter.flush();
return editor;
}
/**
* Returns the directory where this cache stores its data.
*/
public File getDirectory() {
return directory;
}
/**
* Returns the maximum number of bytes that this cache should use to store
* its data.
*/
public long maxSize() {
return maxSize;
}
/**
* Returns the number of bytes currently being used to store the values in
* this cache. This may be greater than the max size if a background
* deletion is pending.
*/
public synchronized long size() {
return size;
}
private synchronized void completeEdit(Editor editor, boolean success) throws IOException {
Entry entry = editor.entry;
if (entry.currentEditor != editor) {
throw new IllegalStateException();
}
// if this edit is creating the entry for the first time, every index must have a value
if (success && !entry.readable) {
for (int i = 0; i < valueCount; i++) {
if (!entry.getDirtyFile(i).exists()) {
editor.abort();
throw new IllegalStateException("edit didn't create file " + i);
}
}
}
for (int i = 0; i < valueCount; i++) {
File dirty = entry.getDirtyFile(i);
if (success) {
if (dirty.exists()) {
File clean = entry.getCleanFile(i);
dirty.renameTo(clean);
long oldLength = entry.lengths[i];
long newLength = clean.length();
entry.lengths[i] = newLength;
size = size - oldLength + newLength;
}
} else {
deleteIfExists(dirty);
}
}
redundantOpCount++;
entry.currentEditor = null;
if (entry.readable | success) {
entry.readable = true;
journalWriter.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n');
if (success) {
entry.sequenceNumber = nextSequenceNumber++;
}
} else {
lruEntries.remove(entry.key);
journalWriter.write(REMOVE + ' ' + entry.key + '\n');
}
if (size > maxSize || journalRebuildRequired()) {
executorService.submit(cleanupCallable);
}
}
/**
* We only rebuild the journal when it will halve the size of the journal
* and eliminate at least 2000 ops.
*/
private boolean journalRebuildRequired() {
final int REDUNDANT_OP_COMPACT_THRESHOLD = 2000;
return redundantOpCount >= REDUNDANT_OP_COMPACT_THRESHOLD
&& redundantOpCount >= lruEntries.size();
}
/**
* Drops the entry for {@code key} if it exists and can be removed. Entries
* actively being edited cannot be removed.
*
* @return true if an entry was removed.
*/
public synchronized boolean remove(String key) throws IOException {
checkNotClosed();
validateKey(key);
Entry entry = lruEntries.get(key);
if (entry == null || entry.currentEditor != null) {
return false;
}
for (int i = 0; i < valueCount; i++) {
File file = entry.getCleanFile(i);
if (!file.delete()) {
throw new IOException("failed to delete " + file);
}
size -= entry.lengths[i];
entry.lengths[i] = 0;
}
redundantOpCount++;
journalWriter.append(REMOVE + ' ' + key + '\n');
lruEntries.remove(key);
if (journalRebuildRequired()) {
executorService.submit(cleanupCallable);
}
return true;
}
/**
* Returns true if this cache has been closed.
*/
public boolean isClosed() {
return journalWriter == null;
}
private void checkNotClosed() {
if (journalWriter == null) {
throw new IllegalStateException("cache is closed");
}
}
/**
* Force buffered operations to the filesystem.
*/
public synchronized void flush() throws IOException {
checkNotClosed();
trimToSize();
journalWriter.flush();
}
/**
* Closes this cache. Stored values will remain on the filesystem.
*/
public synchronized void close() throws IOException {
if (journalWriter == null) {
return; // already closed
}
for (Entry entry : new ArrayList<Entry>(lruEntries.values())) {
if (entry.currentEditor != null) {
entry.currentEditor.abort();
}
}
trimToSize();
journalWriter.close();
journalWriter = null;
}
private void trimToSize() throws IOException {
while (size > maxSize) {
// Map.Entry<String, Entry> toEvict = lruEntries.eldest();
final Map.Entry<String, Entry> toEvict = lruEntries.entrySet().iterator().next();
remove(toEvict.getKey());
}
}
/**
* Closes the cache and deletes all of its stored values. This will delete
* all files in the cache directory including files that weren't created by
* the cache.
*/
public void delete() throws IOException {
close();
deleteContents(directory);
}
private void validateKey(String key) {
if (key.contains(" ") || key.contains("\n") || key.contains("\r")) {
throw new IllegalArgumentException(
"keys must not contain spaces or newlines: \"" + key + "\"");
}
}
private static String inputStreamToString(InputStream in) throws IOException {
return readFully(new InputStreamReader(in, UTF_8));
}
/**
* A snapshot of the values for an entry.
*/
public final class Snapshot implements Closeable {
private final String key;
private final long sequenceNumber;
private final InputStream[] ins;
private Snapshot(String key, long sequenceNumber, InputStream[] ins) {
this.key = key;
this.sequenceNumber = sequenceNumber;
this.ins = ins;
}
/**
* Returns an editor for this snapshot's entry, or null if either the
* entry has changed since this snapshot was created or if another edit
* is in progress.
*/
public Editor edit() throws IOException {
return DiskLruCache.this.edit(key, sequenceNumber);
}
/**
* Returns the unbuffered stream with the value for {@code index}.
*/
public InputStream getInputStream(int index) {
return ins[index];
}
/**
* Returns the string value for {@code index}.
*/
public String getString(int index) throws IOException {
return inputStreamToString(getInputStream(index));
}
@Override public void close() {
for (InputStream in : ins) {
closeQuietly(in);
}
}
}
/**
* Edits the values for an entry.
*/
public final class Editor {
private final Entry entry;
private boolean hasErrors;
private Editor(Entry entry) {
this.entry = entry;
}
/**
* Returns an unbuffered input stream to read the last committed value,
* or null if no value has been committed.
*/
public InputStream newInputStream(int index) throws IOException {
synchronized (DiskLruCache.this) {
if (entry.currentEditor != this) {
throw new IllegalStateException();
}
if (!entry.readable) {
return null;
}
return new FileInputStream(entry.getCleanFile(index));
}
}
/**
* Returns the last committed value as a string, or null if no value
* has been committed.
*/
public String getString(int index) throws IOException {
InputStream in = newInputStream(index);
return in != null ? inputStreamToString(in) : null;
}
/**
* Returns a new unbuffered output stream to write the value at
* {@code index}. If the underlying output stream encounters errors
* when writing to the filesystem, this edit will be aborted when
* {@link #commit} is called. The returned output stream does not throw
* IOExceptions.
*/
public OutputStream newOutputStream(int index) throws IOException {
synchronized (DiskLruCache.this) {
if (entry.currentEditor != this) {
throw new IllegalStateException();
}
return new FaultHidingOutputStream(new FileOutputStream(entry.getDirtyFile(index)));
}
}
/**
* Sets the value at {@code index} to {@code value}.
*/
public void set(int index, String value) throws IOException {
Writer writer = null;
try {
writer = new OutputStreamWriter(newOutputStream(index), UTF_8);
writer.write(value);
} finally {
closeQuietly(writer);
}
}
/**
* Commits this edit so it is visible to readers. This releases the
* edit lock so another edit may be started on the same key.
*/
public void commit() throws IOException {
if (hasErrors) {
completeEdit(this, false);
remove(entry.key); // the previous entry is stale
} else {
completeEdit(this, true);
}
}
/**
* Aborts this edit. This releases the edit lock so another edit may be
* started on the same key.
*/
public void abort() throws IOException {
completeEdit(this, false);
}
private class FaultHidingOutputStream extends FilterOutputStream {
private FaultHidingOutputStream(OutputStream out) {
super(out);
}
@Override public void write(int oneByte) {
try {
out.write(oneByte);
} catch (IOException e) {
hasErrors = true;
}
}
@Override public void write(byte[] buffer, int offset, int length) {
try {
out.write(buffer, offset, length);
} catch (IOException e) {
hasErrors = true;
}
}
@Override public void close() {
try {
out.close();
} catch (IOException e) {
hasErrors = true;
}
}
@Override public void flush() {
try {
out.flush();
} catch (IOException e) {
hasErrors = true;
}
}
}
}
private final class Entry {
private final String key;
/** Lengths of this entry's files. */
private final long[] lengths;
/** True if this entry has ever been published */
private boolean readable;
/** The ongoing edit or null if this entry is not being edited. */
private Editor currentEditor;
/** The sequence number of the most recently committed edit to this entry. */
private long sequenceNumber;
private Entry(String key) {
this.key = key;
this.lengths = new long[valueCount];
}
public String getLengths() throws IOException {
StringBuilder result = new StringBuilder();
for (long size : lengths) {
result.append(' ').append(size);
}
return result.toString();
}
/**
* Set lengths using decimal numbers like "10123".
*/
private void setLengths(String[] strings) throws IOException {
if (strings.length != valueCount) {
throw invalidLengths(strings);
}
try {
for (int i = 0; i < strings.length; i++) {
lengths[i] = Long.parseLong(strings[i]);
}
} catch (NumberFormatException e) {
throw invalidLengths(strings);
}
}
private IOException invalidLengths(String[] strings) throws IOException {
throw new IOException("unexpected journal line: " + Arrays.toString(strings));
}
public File getCleanFile(int i) {
return new File(directory, key + "." + i);
}
public File getDirtyFile(int i) {
return new File(directory, key + "." + i + ".tmp");
}
}
}

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samples/browseable/DisplayingBitmaps/src/com.example.android.displayingbitmaps/util/ImageCache.java Normal file
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@@ -0,0 +1,738 @@
/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import android.annotation.TargetApi;
import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.Bitmap.CompressFormat;
import android.graphics.Bitmap.Config;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.os.Build.VERSION_CODES;
import android.os.Bundle;
import android.os.Environment;
import android.os.StatFs;
import android.support.v4.app.Fragment;
import android.support.v4.app.FragmentManager;
import android.support.v4.util.LruCache;
import com.example.android.common.logger.Log;
import com.example.android.displayingbitmaps.BuildConfig;
import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.lang.ref.SoftReference;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.Collections;
import java.util.HashSet;
import java.util.Iterator;
import java.util.Set;
/**
* This class handles disk and memory caching of bitmaps in conjunction with the
* {@link ImageWorker} class and its subclasses. Use
* {@link ImageCache#getInstance(android.support.v4.app.FragmentManager, ImageCacheParams)} to get an instance of this
* class, although usually a cache should be added directly to an {@link ImageWorker} by calling
* {@link ImageWorker#addImageCache(android.support.v4.app.FragmentManager, ImageCacheParams)}.
*/
public class ImageCache {
private static final String TAG = "ImageCache";
// Default memory cache size in kilobytes
private static final int DEFAULT_MEM_CACHE_SIZE = 1024 * 5; // 5MB
// Default disk cache size in bytes
private static final int DEFAULT_DISK_CACHE_SIZE = 1024 * 1024 * 10; // 10MB
// Compression settings when writing images to disk cache
private static final CompressFormat DEFAULT_COMPRESS_FORMAT = CompressFormat.JPEG;
private static final int DEFAULT_COMPRESS_QUALITY = 70;
private static final int DISK_CACHE_INDEX = 0;
// Constants to easily toggle various caches
private static final boolean DEFAULT_MEM_CACHE_ENABLED = true;
private static final boolean DEFAULT_DISK_CACHE_ENABLED = true;
private static final boolean DEFAULT_INIT_DISK_CACHE_ON_CREATE = false;
private DiskLruCache mDiskLruCache;
private LruCache<String, BitmapDrawable> mMemoryCache;
private ImageCacheParams mCacheParams;
private final Object mDiskCacheLock = new Object();
private boolean mDiskCacheStarting = true;
private Set<SoftReference<Bitmap>> mReusableBitmaps;
/**
* Create a new ImageCache object using the specified parameters. This should not be
* called directly by other classes, instead use
* {@link ImageCache#getInstance(android.support.v4.app.FragmentManager, ImageCacheParams)} to fetch an ImageCache
* instance.
*
* @param cacheParams The cache parameters to use to initialize the cache
*/
private ImageCache(ImageCacheParams cacheParams) {
init(cacheParams);
}
/**
* Return an {@link ImageCache} instance. A {@link RetainFragment} is used to retain the
* ImageCache object across configuration changes such as a change in device orientation.
*
* @param fragmentManager The fragment manager to use when dealing with the retained fragment.
* @param cacheParams The cache parameters to use if the ImageCache needs instantiation.
* @return An existing retained ImageCache object or a new one if one did not exist
*/
public static ImageCache getInstance(
FragmentManager fragmentManager, ImageCacheParams cacheParams) {
// Search for, or create an instance of the non-UI RetainFragment
final RetainFragment mRetainFragment = findOrCreateRetainFragment(fragmentManager);
// See if we already have an ImageCache stored in RetainFragment
ImageCache imageCache = (ImageCache) mRetainFragment.getObject();
// No existing ImageCache, create one and store it in RetainFragment
if (imageCache == null) {
imageCache = new ImageCache(cacheParams);
mRetainFragment.setObject(imageCache);
}
return imageCache;
}
/**
* Initialize the cache, providing all parameters.
*
* @param cacheParams The cache parameters to initialize the cache
*/
private void init(ImageCacheParams cacheParams) {
mCacheParams = cacheParams;
//BEGIN_INCLUDE(init_memory_cache)
// Set up memory cache
if (mCacheParams.memoryCacheEnabled) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "Memory cache created (size = " + mCacheParams.memCacheSize + ")");
}
// If we're running on Honeycomb or newer, create a set of reusable bitmaps that can be
// populated into the inBitmap field of BitmapFactory.Options. Note that the set is
// of SoftReferences which will actually not be very effective due to the garbage
// collector being aggressive clearing Soft/WeakReferences. A better approach
// would be to use a strongly references bitmaps, however this would require some
// balancing of memory usage between this set and the bitmap LruCache. It would also
// require knowledge of the expected size of the bitmaps. From Honeycomb to JellyBean
// the size would need to be precise, from KitKat onward the size would just need to
// be the upper bound (due to changes in how inBitmap can re-use bitmaps).
if (Utils.hasHoneycomb()) {
mReusableBitmaps =
Collections.synchronizedSet(new HashSet<SoftReference<Bitmap>>());
}
mMemoryCache = new LruCache<String, BitmapDrawable>(mCacheParams.memCacheSize) {
/**
* Notify the removed entry that is no longer being cached
*/
@Override
protected void entryRemoved(boolean evicted, String key,
BitmapDrawable oldValue, BitmapDrawable newValue) {
if (RecyclingBitmapDrawable.class.isInstance(oldValue)) {
// The removed entry is a recycling drawable, so notify it
// that it has been removed from the memory cache
((RecyclingBitmapDrawable) oldValue).setIsCached(false);
} else {
// The removed entry is a standard BitmapDrawable
if (Utils.hasHoneycomb()) {
// We're running on Honeycomb or later, so add the bitmap
// to a SoftReference set for possible use with inBitmap later
mReusableBitmaps.add(new SoftReference<Bitmap>(oldValue.getBitmap()));
}
}
}
/**
* Measure item size in kilobytes rather than units which is more practical
* for a bitmap cache
*/
@Override
protected int sizeOf(String key, BitmapDrawable value) {
final int bitmapSize = getBitmapSize(value) / 1024;
return bitmapSize == 0 ? 1 : bitmapSize;
}
};
}
//END_INCLUDE(init_memory_cache)
// By default the disk cache is not initialized here as it should be initialized
// on a separate thread due to disk access.
if (cacheParams.initDiskCacheOnCreate) {
// Set up disk cache
initDiskCache();
}
}
/**
* Initializes the disk cache. Note that this includes disk access so this should not be
* executed on the main/UI thread. By default an ImageCache does not initialize the disk
* cache when it is created, instead you should call initDiskCache() to initialize it on a
* background thread.
*/
public void initDiskCache() {
// Set up disk cache
synchronized (mDiskCacheLock) {
if (mDiskLruCache == null || mDiskLruCache.isClosed()) {
File diskCacheDir = mCacheParams.diskCacheDir;
if (mCacheParams.diskCacheEnabled && diskCacheDir != null) {
if (!diskCacheDir.exists()) {
diskCacheDir.mkdirs();
}
if (getUsableSpace(diskCacheDir) > mCacheParams.diskCacheSize) {
try {
mDiskLruCache = DiskLruCache.open(
diskCacheDir, 1, 1, mCacheParams.diskCacheSize);
if (BuildConfig.DEBUG) {
Log.d(TAG, "Disk cache initialized");
}
} catch (final IOException e) {
mCacheParams.diskCacheDir = null;
Log.e(TAG, "initDiskCache - " + e);
}
}
}
}
mDiskCacheStarting = false;
mDiskCacheLock.notifyAll();
}
}
/**
* Adds a bitmap to both memory and disk cache.
* @param data Unique identifier for the bitmap to store
* @param value The bitmap drawable to store
*/
public void addBitmapToCache(String data, BitmapDrawable value) {
//BEGIN_INCLUDE(add_bitmap_to_cache)
if (data == null || value == null) {
return;
}
// Add to memory cache
if (mMemoryCache != null) {
if (RecyclingBitmapDrawable.class.isInstance(value)) {
// The removed entry is a recycling drawable, so notify it
// that it has been added into the memory cache
((RecyclingBitmapDrawable) value).setIsCached(true);
}
mMemoryCache.put(data, value);
}
synchronized (mDiskCacheLock) {
// Add to disk cache
if (mDiskLruCache != null) {
final String key = hashKeyForDisk(data);
OutputStream out = null;
try {
DiskLruCache.Snapshot snapshot = mDiskLruCache.get(key);
if (snapshot == null) {
final DiskLruCache.Editor editor = mDiskLruCache.edit(key);
if (editor != null) {
out = editor.newOutputStream(DISK_CACHE_INDEX);
value.getBitmap().compress(
mCacheParams.compressFormat, mCacheParams.compressQuality, out);
editor.commit();
out.close();
}
} else {
snapshot.getInputStream(DISK_CACHE_INDEX).close();
}
} catch (final IOException e) {
Log.e(TAG, "addBitmapToCache - " + e);
} catch (Exception e) {
Log.e(TAG, "addBitmapToCache - " + e);
} finally {
try {
if (out != null) {
out.close();
}
} catch (IOException e) {}
}
}
}
//END_INCLUDE(add_bitmap_to_cache)
}
/**
* Get from memory cache.
*
* @param data Unique identifier for which item to get
* @return The bitmap drawable if found in cache, null otherwise
*/
public BitmapDrawable getBitmapFromMemCache(String data) {
//BEGIN_INCLUDE(get_bitmap_from_mem_cache)
BitmapDrawable memValue = null;
if (mMemoryCache != null) {
memValue = mMemoryCache.get(data);
}
if (BuildConfig.DEBUG && memValue != null) {
Log.d(TAG, "Memory cache hit");
}
return memValue;
//END_INCLUDE(get_bitmap_from_mem_cache)
}
/**
* Get from disk cache.
*
* @param data Unique identifier for which item to get
* @return The bitmap if found in cache, null otherwise
*/
public Bitmap getBitmapFromDiskCache(String data) {
//BEGIN_INCLUDE(get_bitmap_from_disk_cache)
final String key = hashKeyForDisk(data);
Bitmap bitmap = null;
synchronized (mDiskCacheLock) {
while (mDiskCacheStarting) {
try {
mDiskCacheLock.wait();
} catch (InterruptedException e) {}
}
if (mDiskLruCache != null) {
InputStream inputStream = null;
try {
final DiskLruCache.Snapshot snapshot = mDiskLruCache.get(key);
if (snapshot != null) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "Disk cache hit");
}
inputStream = snapshot.getInputStream(DISK_CACHE_INDEX);
if (inputStream != null) {
FileDescriptor fd = ((FileInputStream) inputStream).getFD();
// Decode bitmap, but we don't want to sample so give
// MAX_VALUE as the target dimensions
bitmap = ImageResizer.decodeSampledBitmapFromDescriptor(
fd, Integer.MAX_VALUE, Integer.MAX_VALUE, this);
}
}
} catch (final IOException e) {
Log.e(TAG, "getBitmapFromDiskCache - " + e);
} finally {
try {
if (inputStream != null) {
inputStream.close();
}
} catch (IOException e) {}
}
}
return bitmap;
}
//END_INCLUDE(get_bitmap_from_disk_cache)
}
/**
* @param options - BitmapFactory.Options with out* options populated
* @return Bitmap that case be used for inBitmap
*/
protected Bitmap getBitmapFromReusableSet(BitmapFactory.Options options) {
//BEGIN_INCLUDE(get_bitmap_from_reusable_set)
Bitmap bitmap = null;
if (mReusableBitmaps != null && !mReusableBitmaps.isEmpty()) {
synchronized (mReusableBitmaps) {
final Iterator<SoftReference<Bitmap>> iterator = mReusableBitmaps.iterator();
Bitmap item;
while (iterator.hasNext()) {
item = iterator.next().get();
if (null != item && item.isMutable()) {
// Check to see it the item can be used for inBitmap
if (canUseForInBitmap(item, options)) {
bitmap = item;
// Remove from reusable set so it can't be used again
iterator.remove();
break;
}
} else {
// Remove from the set if the reference has been cleared.
iterator.remove();
}
}
}
}
return bitmap;
//END_INCLUDE(get_bitmap_from_reusable_set)
}
/**
* Clears both the memory and disk cache associated with this ImageCache object. Note that
* this includes disk access so this should not be executed on the main/UI thread.
*/
public void clearCache() {
if (mMemoryCache != null) {
mMemoryCache.evictAll();
if (BuildConfig.DEBUG) {
Log.d(TAG, "Memory cache cleared");
}
}
synchronized (mDiskCacheLock) {
mDiskCacheStarting = true;
if (mDiskLruCache != null && !mDiskLruCache.isClosed()) {
try {
mDiskLruCache.delete();
if (BuildConfig.DEBUG) {
Log.d(TAG, "Disk cache cleared");
}
} catch (IOException e) {
Log.e(TAG, "clearCache - " + e);
}
mDiskLruCache = null;
initDiskCache();
}
}
}
/**
* Flushes the disk cache associated with this ImageCache object. Note that this includes
* disk access so this should not be executed on the main/UI thread.
*/
public void flush() {
synchronized (mDiskCacheLock) {
if (mDiskLruCache != null) {
try {
mDiskLruCache.flush();
if (BuildConfig.DEBUG) {
Log.d(TAG, "Disk cache flushed");
}
} catch (IOException e) {
Log.e(TAG, "flush - " + e);
}
}
}
}
/**
* Closes the disk cache associated with this ImageCache object. Note that this includes
* disk access so this should not be executed on the main/UI thread.
*/
public void close() {
synchronized (mDiskCacheLock) {
if (mDiskLruCache != null) {
try {
if (!mDiskLruCache.isClosed()) {
mDiskLruCache.close();
mDiskLruCache = null;
if (BuildConfig.DEBUG) {
Log.d(TAG, "Disk cache closed");
}
}
} catch (IOException e) {
Log.e(TAG, "close - " + e);
}
}
}
}
/**
* A holder class that contains cache parameters.
*/
public static class ImageCacheParams {
public int memCacheSize = DEFAULT_MEM_CACHE_SIZE;
public int diskCacheSize = DEFAULT_DISK_CACHE_SIZE;
public File diskCacheDir;
public CompressFormat compressFormat = DEFAULT_COMPRESS_FORMAT;
public int compressQuality = DEFAULT_COMPRESS_QUALITY;
public boolean memoryCacheEnabled = DEFAULT_MEM_CACHE_ENABLED;
public boolean diskCacheEnabled = DEFAULT_DISK_CACHE_ENABLED;
public boolean initDiskCacheOnCreate = DEFAULT_INIT_DISK_CACHE_ON_CREATE;
/**
* Create a set of image cache parameters that can be provided to
* {@link ImageCache#getInstance(android.support.v4.app.FragmentManager, ImageCacheParams)} or
* {@link ImageWorker#addImageCache(android.support.v4.app.FragmentManager, ImageCacheParams)}.
* @param context A context to use.
* @param diskCacheDirectoryName A unique subdirectory name that will be appended to the
* application cache directory. Usually "cache" or "images"
* is sufficient.
*/
public ImageCacheParams(Context context, String diskCacheDirectoryName) {
diskCacheDir = getDiskCacheDir(context, diskCacheDirectoryName);
}
/**
* Sets the memory cache size based on a percentage of the max available VM memory.
* Eg. setting percent to 0.2 would set the memory cache to one fifth of the available
* memory. Throws {@link IllegalArgumentException} if percent is < 0.01 or > .8.
* memCacheSize is stored in kilobytes instead of bytes as this will eventually be passed
* to construct a LruCache which takes an int in its constructor.
*
* This value should be chosen carefully based on a number of factors
* Refer to the corresponding Android Training class for more discussion:
* http://developer.android.com/training/displaying-bitmaps/
*
* @param percent Percent of available app memory to use to size memory cache
*/
public void setMemCacheSizePercent(float percent) {
if (percent < 0.01f || percent > 0.8f) {
throw new IllegalArgumentException("setMemCacheSizePercent - percent must be "
+ "between 0.01 and 0.8 (inclusive)");
}
memCacheSize = Math.round(percent * Runtime.getRuntime().maxMemory() / 1024);
}
}
/**
* @param candidate - Bitmap to check
* @param targetOptions - Options that have the out* value populated
* @return true if <code>candidate</code> can be used for inBitmap re-use with
* <code>targetOptions</code>
*/
@TargetApi(VERSION_CODES.KITKAT)
private static boolean canUseForInBitmap(
Bitmap candidate, BitmapFactory.Options targetOptions) {
//BEGIN_INCLUDE(can_use_for_inbitmap)
if (!Utils.hasKitKat()) {
// On earlier versions, the dimensions must match exactly and the inSampleSize must be 1
return candidate.getWidth() == targetOptions.outWidth
&& candidate.getHeight() == targetOptions.outHeight
&& targetOptions.inSampleSize == 1;
}
// From Android 4.4 (KitKat) onward we can re-use if the byte size of the new bitmap
// is smaller than the reusable bitmap candidate allocation byte count.
int width = targetOptions.outWidth / targetOptions.inSampleSize;
int height = targetOptions.outHeight / targetOptions.inSampleSize;
int byteCount = width * height * getBytesPerPixel(candidate.getConfig());
return byteCount <= candidate.getAllocationByteCount();
//END_INCLUDE(can_use_for_inbitmap)
}
/**
* Return the byte usage per pixel of a bitmap based on its configuration.
* @param config The bitmap configuration.
* @return The byte usage per pixel.
*/
private static int getBytesPerPixel(Config config) {
if (config == Config.ARGB_8888) {
return 4;
} else if (config == Config.RGB_565) {
return 2;
} else if (config == Config.ARGB_4444) {
return 2;
} else if (config == Config.ALPHA_8) {
return 1;
}
return 1;
}
/**
* Get a usable cache directory (external if available, internal otherwise).
*
* @param context The context to use
* @param uniqueName A unique directory name to append to the cache dir
* @return The cache dir
*/
public static File getDiskCacheDir(Context context, String uniqueName) {
// Check if media is mounted or storage is built-in, if so, try and use external cache dir
// otherwise use internal cache dir
final String cachePath =
Environment.MEDIA_MOUNTED.equals(Environment.getExternalStorageState()) ||
!isExternalStorageRemovable() ? getExternalCacheDir(context).getPath() :
context.getCacheDir().getPath();
return new File(cachePath + File.separator + uniqueName);
}
/**
* A hashing method that changes a string (like a URL) into a hash suitable for using as a
* disk filename.
*/
public static String hashKeyForDisk(String key) {
String cacheKey;
try {
final MessageDigest mDigest = MessageDigest.getInstance("MD5");
mDigest.update(key.getBytes());
cacheKey = bytesToHexString(mDigest.digest());
} catch (NoSuchAlgorithmException e) {
cacheKey = String.valueOf(key.hashCode());
}
return cacheKey;
}
private static String bytesToHexString(byte[] bytes) {
// http://stackoverflow.com/questions/332079
StringBuilder sb = new StringBuilder();
for (int i = 0; i < bytes.length; i++) {
String hex = Integer.toHexString(0xFF & bytes[i]);
if (hex.length() == 1) {
sb.append('0');
}
sb.append(hex);
}
return sb.toString();
}
/**
* Get the size in bytes of a bitmap in a BitmapDrawable. Note that from Android 4.4 (KitKat)
* onward this returns the allocated memory size of the bitmap which can be larger than the
* actual bitmap data byte count (in the case it was re-used).
*
* @param value
* @return size in bytes
*/
@TargetApi(VERSION_CODES.KITKAT)
public static int getBitmapSize(BitmapDrawable value) {
Bitmap bitmap = value.getBitmap();
// From KitKat onward use getAllocationByteCount() as allocated bytes can potentially be
// larger than bitmap byte count.
if (Utils.hasKitKat()) {
return bitmap.getAllocationByteCount();
}
if (Utils.hasHoneycombMR1()) {
return bitmap.getByteCount();
}
// Pre HC-MR1
return bitmap.getRowBytes() * bitmap.getHeight();
}
/**
* Check if external storage is built-in or removable.
*
* @return True if external storage is removable (like an SD card), false
* otherwise.
*/
@TargetApi(VERSION_CODES.GINGERBREAD)
public static boolean isExternalStorageRemovable() {
if (Utils.hasGingerbread()) {
return Environment.isExternalStorageRemovable();
}
return true;
}
/**
* Get the external app cache directory.
*
* @param context The context to use
* @return The external cache dir
*/
@TargetApi(VERSION_CODES.FROYO)
public static File getExternalCacheDir(Context context) {
if (Utils.hasFroyo()) {
return context.getExternalCacheDir();
}
// Before Froyo we need to construct the external cache dir ourselves
final String cacheDir = "/Android/data/" + context.getPackageName() + "/cache/";
return new File(Environment.getExternalStorageDirectory().getPath() + cacheDir);
}
/**
* Check how much usable space is available at a given path.
*
* @param path The path to check
* @return The space available in bytes
*/
@TargetApi(VERSION_CODES.GINGERBREAD)
public static long getUsableSpace(File path) {
if (Utils.hasGingerbread()) {
return path.getUsableSpace();
}
final StatFs stats = new StatFs(path.getPath());
return (long) stats.getBlockSize() * (long) stats.getAvailableBlocks();
}
/**
* Locate an existing instance of this Fragment or if not found, create and
* add it using FragmentManager.
*
* @param fm The FragmentManager manager to use.
* @return The existing instance of the Fragment or the new instance if just
* created.
*/
private static RetainFragment findOrCreateRetainFragment(FragmentManager fm) {
//BEGIN_INCLUDE(find_create_retain_fragment)
// Check to see if we have retained the worker fragment.
RetainFragment mRetainFragment = (RetainFragment) fm.findFragmentByTag(TAG);
// If not retained (or first time running), we need to create and add it.
if (mRetainFragment == null) {
mRetainFragment = new RetainFragment();
fm.beginTransaction().add(mRetainFragment, TAG).commitAllowingStateLoss();
}
return mRetainFragment;
//END_INCLUDE(find_create_retain_fragment)
}
/**
* A simple non-UI Fragment that stores a single Object and is retained over configuration
* changes. It will be used to retain the ImageCache object.
*/
public static class RetainFragment extends Fragment {
private Object mObject;
/**
* Empty constructor as per the Fragment documentation
*/
public RetainFragment() {}
@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Make sure this Fragment is retained over a configuration change
setRetainInstance(true);
}
/**
* Store a single object in this Fragment.
*
* @param object The object to store
*/
public void setObject(Object object) {
mObject = object;
}
/**
* Get the stored object.
*
* @return The stored object
*/
public Object getObject() {
return mObject;
}
}
}

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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import android.content.Context;
import android.graphics.Bitmap;
import android.net.ConnectivityManager;
import android.net.NetworkInfo;
import android.os.Build;
import android.widget.Toast;
import com.example.android.common.logger.Log;
import com.example.android.displayingbitmaps.BuildConfig;
import com.example.android.displayingbitmaps.R;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileDescriptor;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.net.HttpURLConnection;
import java.net.URL;
/**
* A simple subclass of {@link ImageResizer} that fetches and resizes images fetched from a URL.
*/
public class ImageFetcher extends ImageResizer {
private static final String TAG = "ImageFetcher";
private static final int HTTP_CACHE_SIZE = 10 * 1024 * 1024; // 10MB
private static final String HTTP_CACHE_DIR = "http";
private static final int IO_BUFFER_SIZE = 8 * 1024;
private DiskLruCache mHttpDiskCache;
private File mHttpCacheDir;
private boolean mHttpDiskCacheStarting = true;
private final Object mHttpDiskCacheLock = new Object();
private static final int DISK_CACHE_INDEX = 0;
/**
* Initialize providing a target image width and height for the processing images.
*
* @param context
* @param imageWidth
* @param imageHeight
*/
public ImageFetcher(Context context, int imageWidth, int imageHeight) {
super(context, imageWidth, imageHeight);
init(context);
}
/**
* Initialize providing a single target image size (used for both width and height);
*
* @param context
* @param imageSize
*/
public ImageFetcher(Context context, int imageSize) {
super(context, imageSize);
init(context);
}
private void init(Context context) {
checkConnection(context);
mHttpCacheDir = ImageCache.getDiskCacheDir(context, HTTP_CACHE_DIR);
}
@Override
protected void initDiskCacheInternal() {
super.initDiskCacheInternal();
initHttpDiskCache();
}
private void initHttpDiskCache() {
if (!mHttpCacheDir.exists()) {
mHttpCacheDir.mkdirs();
}
synchronized (mHttpDiskCacheLock) {
if (ImageCache.getUsableSpace(mHttpCacheDir) > HTTP_CACHE_SIZE) {
try {
mHttpDiskCache = DiskLruCache.open(mHttpCacheDir, 1, 1, HTTP_CACHE_SIZE);
if (BuildConfig.DEBUG) {
Log.d(TAG, "HTTP cache initialized");
}
} catch (IOException e) {
mHttpDiskCache = null;
}
}
mHttpDiskCacheStarting = false;
mHttpDiskCacheLock.notifyAll();
}
}
@Override
protected void clearCacheInternal() {
super.clearCacheInternal();
synchronized (mHttpDiskCacheLock) {
if (mHttpDiskCache != null && !mHttpDiskCache.isClosed()) {
try {
mHttpDiskCache.delete();
if (BuildConfig.DEBUG) {
Log.d(TAG, "HTTP cache cleared");
}
} catch (IOException e) {
Log.e(TAG, "clearCacheInternal - " + e);
}
mHttpDiskCache = null;
mHttpDiskCacheStarting = true;
initHttpDiskCache();
}
}
}
@Override
protected void flushCacheInternal() {
super.flushCacheInternal();
synchronized (mHttpDiskCacheLock) {
if (mHttpDiskCache != null) {
try {
mHttpDiskCache.flush();
if (BuildConfig.DEBUG) {
Log.d(TAG, "HTTP cache flushed");
}
} catch (IOException e) {
Log.e(TAG, "flush - " + e);
}
}
}
}
@Override
protected void closeCacheInternal() {
super.closeCacheInternal();
synchronized (mHttpDiskCacheLock) {
if (mHttpDiskCache != null) {
try {
if (!mHttpDiskCache.isClosed()) {
mHttpDiskCache.close();
mHttpDiskCache = null;
if (BuildConfig.DEBUG) {
Log.d(TAG, "HTTP cache closed");
}
}
} catch (IOException e) {
Log.e(TAG, "closeCacheInternal - " + e);
}
}
}
}
/**
* Simple network connection check.
*
* @param context
*/
private void checkConnection(Context context) {
final ConnectivityManager cm =
(ConnectivityManager) context.getSystemService(Context.CONNECTIVITY_SERVICE);
final NetworkInfo networkInfo = cm.getActiveNetworkInfo();
if (networkInfo == null || !networkInfo.isConnectedOrConnecting()) {
Toast.makeText(context, R.string.no_network_connection_toast, Toast.LENGTH_LONG).show();
Log.e(TAG, "checkConnection - no connection found");
}
}
/**
* The main process method, which will be called by the ImageWorker in the AsyncTask background
* thread.
*
* @param data The data to load the bitmap, in this case, a regular http URL
* @return The downloaded and resized bitmap
*/
private Bitmap processBitmap(String data) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "processBitmap - " + data);
}
final String key = ImageCache.hashKeyForDisk(data);
FileDescriptor fileDescriptor = null;
FileInputStream fileInputStream = null;
DiskLruCache.Snapshot snapshot;
synchronized (mHttpDiskCacheLock) {
// Wait for disk cache to initialize
while (mHttpDiskCacheStarting) {
try {
mHttpDiskCacheLock.wait();
} catch (InterruptedException e) {}
}
if (mHttpDiskCache != null) {
try {
snapshot = mHttpDiskCache.get(key);
if (snapshot == null) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "processBitmap, not found in http cache, downloading...");
}
DiskLruCache.Editor editor = mHttpDiskCache.edit(key);
if (editor != null) {
if (downloadUrlToStream(data,
editor.newOutputStream(DISK_CACHE_INDEX))) {
editor.commit();
} else {
editor.abort();
}
}
snapshot = mHttpDiskCache.get(key);
}
if (snapshot != null) {
fileInputStream =
(FileInputStream) snapshot.getInputStream(DISK_CACHE_INDEX);
fileDescriptor = fileInputStream.getFD();
}
} catch (IOException e) {
Log.e(TAG, "processBitmap - " + e);
} catch (IllegalStateException e) {
Log.e(TAG, "processBitmap - " + e);
} finally {
if (fileDescriptor == null && fileInputStream != null) {
try {
fileInputStream.close();
} catch (IOException e) {}
}
}
}
}
Bitmap bitmap = null;
if (fileDescriptor != null) {
bitmap = decodeSampledBitmapFromDescriptor(fileDescriptor, mImageWidth,
mImageHeight, getImageCache());
}
if (fileInputStream != null) {
try {
fileInputStream.close();
} catch (IOException e) {}
}
return bitmap;
}
@Override
protected Bitmap processBitmap(Object data) {
return processBitmap(String.valueOf(data));
}
/**
* Download a bitmap from a URL and write the content to an output stream.
*
* @param urlString The URL to fetch
* @return true if successful, false otherwise
*/
public boolean downloadUrlToStream(String urlString, OutputStream outputStream) {
disableConnectionReuseIfNecessary();
HttpURLConnection urlConnection = null;
BufferedOutputStream out = null;
BufferedInputStream in = null;
try {
final URL url = new URL(urlString);
urlConnection = (HttpURLConnection) url.openConnection();
in = new BufferedInputStream(urlConnection.getInputStream(), IO_BUFFER_SIZE);
out = new BufferedOutputStream(outputStream, IO_BUFFER_SIZE);
int b;
while ((b = in.read()) != -1) {
out.write(b);
}
return true;
} catch (final IOException e) {
Log.e(TAG, "Error in downloadBitmap - " + e);
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
try {
if (out != null) {
out.close();
}
if (in != null) {
in.close();
}
} catch (final IOException e) {}
}
return false;
}
/**
* Workaround for bug pre-Froyo, see here for more info:
* http://android-developers.blogspot.com/2011/09/androids-http-clients.html
*/
public static void disableConnectionReuseIfNecessary() {
// HTTP connection reuse which was buggy pre-froyo
if (Build.VERSION.SDK_INT < Build.VERSION_CODES.FROYO) {
System.setProperty("http.keepAlive", "false");
}
}
}

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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import android.annotation.TargetApi;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.os.Build;
import com.example.android.common.logger.Log;
import com.example.android.displayingbitmaps.BuildConfig;
import java.io.FileDescriptor;
/**
* A simple subclass of {@link ImageWorker} that resizes images from resources given a target width
* and height. Useful for when the input images might be too large to simply load directly into
* memory.
*/
public class ImageResizer extends ImageWorker {
private static final String TAG = "ImageResizer";
protected int mImageWidth;
protected int mImageHeight;
/**
* Initialize providing a single target image size (used for both width and height);
*
* @param context
* @param imageWidth
* @param imageHeight
*/
public ImageResizer(Context context, int imageWidth, int imageHeight) {
super(context);
setImageSize(imageWidth, imageHeight);
}
/**
* Initialize providing a single target image size (used for both width and height);
*
* @param context
* @param imageSize
*/
public ImageResizer(Context context, int imageSize) {
super(context);
setImageSize(imageSize);
}
/**
* Set the target image width and height.
*
* @param width
* @param height
*/
public void setImageSize(int width, int height) {
mImageWidth = width;
mImageHeight = height;
}
/**
* Set the target image size (width and height will be the same).
*
* @param size
*/
public void setImageSize(int size) {
setImageSize(size, size);
}
/**
* The main processing method. This happens in a background task. In this case we are just
* sampling down the bitmap and returning it from a resource.
*
* @param resId
* @return
*/
private Bitmap processBitmap(int resId) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "processBitmap - " + resId);
}
return decodeSampledBitmapFromResource(mResources, resId, mImageWidth,
mImageHeight, getImageCache());
}
@Override
protected Bitmap processBitmap(Object data) {
return processBitmap(Integer.parseInt(String.valueOf(data)));
}
/**
* Decode and sample down a bitmap from resources to the requested width and height.
*
* @param res The resources object containing the image data
* @param resId The resource id of the image data
* @param reqWidth The requested width of the resulting bitmap
* @param reqHeight The requested height of the resulting bitmap
* @param cache The ImageCache used to find candidate bitmaps for use with inBitmap
* @return A bitmap sampled down from the original with the same aspect ratio and dimensions
* that are equal to or greater than the requested width and height
*/
public static Bitmap decodeSampledBitmapFromResource(Resources res, int resId,
int reqWidth, int reqHeight, ImageCache cache) {
// BEGIN_INCLUDE (read_bitmap_dimensions)
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeResource(res, resId, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// END_INCLUDE (read_bitmap_dimensions)
// If we're running on Honeycomb or newer, try to use inBitmap
if (Utils.hasHoneycomb()) {
addInBitmapOptions(options, cache);
}
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeResource(res, resId, options);
}
/**
* Decode and sample down a bitmap from a file to the requested width and height.
*
* @param filename The full path of the file to decode
* @param reqWidth The requested width of the resulting bitmap
* @param reqHeight The requested height of the resulting bitmap
* @param cache The ImageCache used to find candidate bitmaps for use with inBitmap
* @return A bitmap sampled down from the original with the same aspect ratio and dimensions
* that are equal to or greater than the requested width and height
*/
public static Bitmap decodeSampledBitmapFromFile(String filename,
int reqWidth, int reqHeight, ImageCache cache) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFile(filename, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// If we're running on Honeycomb or newer, try to use inBitmap
if (Utils.hasHoneycomb()) {
addInBitmapOptions(options, cache);
}
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
return BitmapFactory.decodeFile(filename, options);
}
/**
* Decode and sample down a bitmap from a file input stream to the requested width and height.
*
* @param fileDescriptor The file descriptor to read from
* @param reqWidth The requested width of the resulting bitmap
* @param reqHeight The requested height of the resulting bitmap
* @param cache The ImageCache used to find candidate bitmaps for use with inBitmap
* @return A bitmap sampled down from the original with the same aspect ratio and dimensions
* that are equal to or greater than the requested width and height
*/
public static Bitmap decodeSampledBitmapFromDescriptor(
FileDescriptor fileDescriptor, int reqWidth, int reqHeight, ImageCache cache) {
// First decode with inJustDecodeBounds=true to check dimensions
final BitmapFactory.Options options = new BitmapFactory.Options();
options.inJustDecodeBounds = true;
BitmapFactory.decodeFileDescriptor(fileDescriptor, null, options);
// Calculate inSampleSize
options.inSampleSize = calculateInSampleSize(options, reqWidth, reqHeight);
// Decode bitmap with inSampleSize set
options.inJustDecodeBounds = false;
// If we're running on Honeycomb or newer, try to use inBitmap
if (Utils.hasHoneycomb()) {
addInBitmapOptions(options, cache);
}
return BitmapFactory.decodeFileDescriptor(fileDescriptor, null, options);
}
@TargetApi(Build.VERSION_CODES.HONEYCOMB)
private static void addInBitmapOptions(BitmapFactory.Options options, ImageCache cache) {
//BEGIN_INCLUDE(add_bitmap_options)
// inBitmap only works with mutable bitmaps so force the decoder to
// return mutable bitmaps.
options.inMutable = true;
if (cache != null) {
// Try and find a bitmap to use for inBitmap
Bitmap inBitmap = cache.getBitmapFromReusableSet(options);
if (inBitmap != null) {
options.inBitmap = inBitmap;
}
}
//END_INCLUDE(add_bitmap_options)
}
/**
* Calculate an inSampleSize for use in a {@link android.graphics.BitmapFactory.Options} object when decoding
* bitmaps using the decode* methods from {@link android.graphics.BitmapFactory}. This implementation calculates
* the closest inSampleSize that is a power of 2 and will result in the final decoded bitmap
* having a width and height equal to or larger than the requested width and height.
*
* @param options An options object with out* params already populated (run through a decode*
* method with inJustDecodeBounds==true
* @param reqWidth The requested width of the resulting bitmap
* @param reqHeight The requested height of the resulting bitmap
* @return The value to be used for inSampleSize
*/
public static int calculateInSampleSize(BitmapFactory.Options options,
int reqWidth, int reqHeight) {
// BEGIN_INCLUDE (calculate_sample_size)
// Raw height and width of image
final int height = options.outHeight;
final int width = options.outWidth;
int inSampleSize = 1;
if (height > reqHeight || width > reqWidth) {
final int halfHeight = height / 2;
final int halfWidth = width / 2;
// Calculate the largest inSampleSize value that is a power of 2 and keeps both
// height and width larger than the requested height and width.
while ((halfHeight / inSampleSize) > reqHeight
&& (halfWidth / inSampleSize) > reqWidth) {
inSampleSize *= 2;
}
// This offers some additional logic in case the image has a strange
// aspect ratio. For example, a panorama may have a much larger
// width than height. In these cases the total pixels might still
// end up being too large to fit comfortably in memory, so we should
// be more aggressive with sample down the image (=larger inSampleSize).
long totalPixels = width * height / inSampleSize;
// Anything more than 2x the requested pixels we'll sample down further
final long totalReqPixelsCap = reqWidth * reqHeight * 2;
while (totalPixels > totalReqPixelsCap) {
inSampleSize *= 2;
totalPixels /= 2;
}
}
return inSampleSize;
// END_INCLUDE (calculate_sample_size)
}
}

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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import android.content.Context;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.drawable.BitmapDrawable;
import android.graphics.drawable.ColorDrawable;
import android.graphics.drawable.Drawable;
import android.graphics.drawable.TransitionDrawable;
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.widget.ImageView;
import com.example.android.common.logger.Log;
import com.example.android.displayingbitmaps.BuildConfig;
import java.lang.ref.WeakReference;
/**
* This class wraps up completing some arbitrary long running work when loading a bitmap to an
* ImageView. It handles things like using a memory and disk cache, running the work in a background
* thread and setting a placeholder image.
*/
public abstract class ImageWorker {
private static final String TAG = "ImageWorker";
private static final int FADE_IN_TIME = 200;
private ImageCache mImageCache;
private ImageCache.ImageCacheParams mImageCacheParams;
private Bitmap mLoadingBitmap;
private boolean mFadeInBitmap = true;
private boolean mExitTasksEarly = false;
protected boolean mPauseWork = false;
private final Object mPauseWorkLock = new Object();
protected Resources mResources;
private static final int MESSAGE_CLEAR = 0;
private static final int MESSAGE_INIT_DISK_CACHE = 1;
private static final int MESSAGE_FLUSH = 2;
private static final int MESSAGE_CLOSE = 3;
protected ImageWorker(Context context) {
mResources = context.getResources();
}
/**
* Load an image specified by the data parameter into an ImageView (override
* {@link ImageWorker#processBitmap(Object)} to define the processing logic). A memory and
* disk cache will be used if an {@link ImageCache} has been added using
* {@link ImageWorker#addImageCache(android.support.v4.app.FragmentManager, ImageCache.ImageCacheParams)}. If the
* image is found in the memory cache, it is set immediately, otherwise an {@link AsyncTask}
* will be created to asynchronously load the bitmap.
*
* @param data The URL of the image to download.
* @param imageView The ImageView to bind the downloaded image to.
*/
public void loadImage(Object data, ImageView imageView) {
if (data == null) {
return;
}
BitmapDrawable value = null;
if (mImageCache != null) {
value = mImageCache.getBitmapFromMemCache(String.valueOf(data));
}
if (value != null) {
// Bitmap found in memory cache
imageView.setImageDrawable(value);
} else if (cancelPotentialWork(data, imageView)) {
//BEGIN_INCLUDE(execute_background_task)
final BitmapWorkerTask task = new BitmapWorkerTask(data, imageView);
final AsyncDrawable asyncDrawable =
new AsyncDrawable(mResources, mLoadingBitmap, task);
imageView.setImageDrawable(asyncDrawable);
// NOTE: This uses a custom version of AsyncTask that has been pulled from the
// framework and slightly modified. Refer to the docs at the top of the class
// for more info on what was changed.
task.executeOnExecutor(AsyncTask.DUAL_THREAD_EXECUTOR);
//END_INCLUDE(execute_background_task)
}
}
/**
* Set placeholder bitmap that shows when the the background thread is running.
*
* @param bitmap
*/
public void setLoadingImage(Bitmap bitmap) {
mLoadingBitmap = bitmap;
}
/**
* Set placeholder bitmap that shows when the the background thread is running.
*
* @param resId
*/
public void setLoadingImage(int resId) {
mLoadingBitmap = BitmapFactory.decodeResource(mResources, resId);
}
/**
* Adds an {@link ImageCache} to this {@link ImageWorker} to handle disk and memory bitmap
* caching.
* @param fragmentManager
* @param cacheParams The cache parameters to use for the image cache.
*/
public void addImageCache(FragmentManager fragmentManager,
ImageCache.ImageCacheParams cacheParams) {
mImageCacheParams = cacheParams;
mImageCache = ImageCache.getInstance(fragmentManager, mImageCacheParams);
new CacheAsyncTask().execute(MESSAGE_INIT_DISK_CACHE);
}
/**
* Adds an {@link ImageCache} to this {@link ImageWorker} to handle disk and memory bitmap
* caching.
* @param activity
* @param diskCacheDirectoryName See
* {@link ImageCache.ImageCacheParams#ImageCacheParams(android.content.Context, String)}.
*/
public void addImageCache(FragmentActivity activity, String diskCacheDirectoryName) {
mImageCacheParams = new ImageCache.ImageCacheParams(activity, diskCacheDirectoryName);
mImageCache = ImageCache.getInstance(activity.getSupportFragmentManager(), mImageCacheParams);
new CacheAsyncTask().execute(MESSAGE_INIT_DISK_CACHE);
}
/**
* If set to true, the image will fade-in once it has been loaded by the background thread.
*/
public void setImageFadeIn(boolean fadeIn) {
mFadeInBitmap = fadeIn;
}
public void setExitTasksEarly(boolean exitTasksEarly) {
mExitTasksEarly = exitTasksEarly;
setPauseWork(false);
}
/**
* Subclasses should override this to define any processing or work that must happen to produce
* the final bitmap. This will be executed in a background thread and be long running. For
* example, you could resize a large bitmap here, or pull down an image from the network.
*
* @param data The data to identify which image to process, as provided by
* {@link ImageWorker#loadImage(Object, android.widget.ImageView)}
* @return The processed bitmap
*/
protected abstract Bitmap processBitmap(Object data);
/**
* @return The {@link ImageCache} object currently being used by this ImageWorker.
*/
protected ImageCache getImageCache() {
return mImageCache;
}
/**
* Cancels any pending work attached to the provided ImageView.
* @param imageView
*/
public static void cancelWork(ImageView imageView) {
final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView);
if (bitmapWorkerTask != null) {
bitmapWorkerTask.cancel(true);
if (BuildConfig.DEBUG) {
final Object bitmapData = bitmapWorkerTask.mData;
Log.d(TAG, "cancelWork - cancelled work for " + bitmapData);
}
}
}
/**
* Returns true if the current work has been canceled or if there was no work in
* progress on this image view.
* Returns false if the work in progress deals with the same data. The work is not
* stopped in that case.
*/
public static boolean cancelPotentialWork(Object data, ImageView imageView) {
//BEGIN_INCLUDE(cancel_potential_work)
final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView);
if (bitmapWorkerTask != null) {
final Object bitmapData = bitmapWorkerTask.mData;
if (bitmapData == null || !bitmapData.equals(data)) {
bitmapWorkerTask.cancel(true);
if (BuildConfig.DEBUG) {
Log.d(TAG, "cancelPotentialWork - cancelled work for " + data);
}
} else {
// The same work is already in progress.
return false;
}
}
return true;
//END_INCLUDE(cancel_potential_work)
}
/**
* @param imageView Any imageView
* @return Retrieve the currently active work task (if any) associated with this imageView.
* null if there is no such task.
*/
private static BitmapWorkerTask getBitmapWorkerTask(ImageView imageView) {
if (imageView != null) {
final Drawable drawable = imageView.getDrawable();
if (drawable instanceof AsyncDrawable) {
final AsyncDrawable asyncDrawable = (AsyncDrawable) drawable;
return asyncDrawable.getBitmapWorkerTask();
}
}
return null;
}
/**
* The actual AsyncTask that will asynchronously process the image.
*/
private class BitmapWorkerTask extends AsyncTask<Void, Void, BitmapDrawable> {
private Object mData;
private final WeakReference<ImageView> imageViewReference;
public BitmapWorkerTask(Object data, ImageView imageView) {
mData = data;
imageViewReference = new WeakReference<ImageView>(imageView);
}
/**
* Background processing.
*/
@Override
protected BitmapDrawable doInBackground(Void... params) {
//BEGIN_INCLUDE(load_bitmap_in_background)
if (BuildConfig.DEBUG) {
Log.d(TAG, "doInBackground - starting work");
}
final String dataString = String.valueOf(mData);
Bitmap bitmap = null;
BitmapDrawable drawable = null;
// Wait here if work is paused and the task is not cancelled
synchronized (mPauseWorkLock) {
while (mPauseWork && !isCancelled()) {
try {
mPauseWorkLock.wait();
} catch (InterruptedException e) {}
}
}
// If the image cache is available and this task has not been cancelled by another
// thread and the ImageView that was originally bound to this task is still bound back
// to this task and our "exit early" flag is not set then try and fetch the bitmap from
// the cache
if (mImageCache != null && !isCancelled() && getAttachedImageView() != null
&& !mExitTasksEarly) {
bitmap = mImageCache.getBitmapFromDiskCache(dataString);
}
// If the bitmap was not found in the cache and this task has not been cancelled by
// another thread and the ImageView that was originally bound to this task is still
// bound back to this task and our "exit early" flag is not set, then call the main
// process method (as implemented by a subclass)
if (bitmap == null && !isCancelled() && getAttachedImageView() != null
&& !mExitTasksEarly) {
bitmap = processBitmap(mData);
}
// If the bitmap was processed and the image cache is available, then add the processed
// bitmap to the cache for future use. Note we don't check if the task was cancelled
// here, if it was, and the thread is still running, we may as well add the processed
// bitmap to our cache as it might be used again in the future
if (bitmap != null) {
if (Utils.hasHoneycomb()) {
// Running on Honeycomb or newer, so wrap in a standard BitmapDrawable
drawable = new BitmapDrawable(mResources, bitmap);
} else {
// Running on Gingerbread or older, so wrap in a RecyclingBitmapDrawable
// which will recycle automagically
drawable = new RecyclingBitmapDrawable(mResources, bitmap);
}
if (mImageCache != null) {
mImageCache.addBitmapToCache(dataString, drawable);
}
}
if (BuildConfig.DEBUG) {
Log.d(TAG, "doInBackground - finished work");
}
return drawable;
//END_INCLUDE(load_bitmap_in_background)
}
/**
* Once the image is processed, associates it to the imageView
*/
@Override
protected void onPostExecute(BitmapDrawable value) {
//BEGIN_INCLUDE(complete_background_work)
// if cancel was called on this task or the "exit early" flag is set then we're done
if (isCancelled() || mExitTasksEarly) {
value = null;
}
final ImageView imageView = getAttachedImageView();
if (value != null && imageView != null) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "onPostExecute - setting bitmap");
}
setImageDrawable(imageView, value);
}
//END_INCLUDE(complete_background_work)
}
@Override
protected void onCancelled(BitmapDrawable value) {
super.onCancelled(value);
synchronized (mPauseWorkLock) {
mPauseWorkLock.notifyAll();
}
}
/**
* Returns the ImageView associated with this task as long as the ImageView's task still
* points to this task as well. Returns null otherwise.
*/
private ImageView getAttachedImageView() {
final ImageView imageView = imageViewReference.get();
final BitmapWorkerTask bitmapWorkerTask = getBitmapWorkerTask(imageView);
if (this == bitmapWorkerTask) {
return imageView;
}
return null;
}
}
/**
* A custom Drawable that will be attached to the imageView while the work is in progress.
* Contains a reference to the actual worker task, so that it can be stopped if a new binding is
* required, and makes sure that only the last started worker process can bind its result,
* independently of the finish order.
*/
private static class AsyncDrawable extends BitmapDrawable {
private final WeakReference<BitmapWorkerTask> bitmapWorkerTaskReference;
public AsyncDrawable(Resources res, Bitmap bitmap, BitmapWorkerTask bitmapWorkerTask) {
super(res, bitmap);
bitmapWorkerTaskReference =
new WeakReference<BitmapWorkerTask>(bitmapWorkerTask);
}
public BitmapWorkerTask getBitmapWorkerTask() {
return bitmapWorkerTaskReference.get();
}
}
/**
* Called when the processing is complete and the final drawable should be
* set on the ImageView.
*
* @param imageView
* @param drawable
*/
private void setImageDrawable(ImageView imageView, Drawable drawable) {
if (mFadeInBitmap) {
// Transition drawable with a transparent drawable and the final drawable
final TransitionDrawable td =
new TransitionDrawable(new Drawable[] {
new ColorDrawable(android.R.color.transparent),
drawable
});
// Set background to loading bitmap
imageView.setBackgroundDrawable(
new BitmapDrawable(mResources, mLoadingBitmap));
imageView.setImageDrawable(td);
td.startTransition(FADE_IN_TIME);
} else {
imageView.setImageDrawable(drawable);
}
}
/**
* Pause any ongoing background work. This can be used as a temporary
* measure to improve performance. For example background work could
* be paused when a ListView or GridView is being scrolled using a
* {@link android.widget.AbsListView.OnScrollListener} to keep
* scrolling smooth.
* <p>
* If work is paused, be sure setPauseWork(false) is called again
* before your fragment or activity is destroyed (for example during
* {@link android.app.Activity#onPause()}), or there is a risk the
* background thread will never finish.
*/
public void setPauseWork(boolean pauseWork) {
synchronized (mPauseWorkLock) {
mPauseWork = pauseWork;
if (!mPauseWork) {
mPauseWorkLock.notifyAll();
}
}
}
protected class CacheAsyncTask extends AsyncTask<Object, Void, Void> {
@Override
protected Void doInBackground(Object... params) {
switch ((Integer)params[0]) {
case MESSAGE_CLEAR:
clearCacheInternal();
break;
case MESSAGE_INIT_DISK_CACHE:
initDiskCacheInternal();
break;
case MESSAGE_FLUSH:
flushCacheInternal();
break;
case MESSAGE_CLOSE:
closeCacheInternal();
break;
}
return null;
}
}
protected void initDiskCacheInternal() {
if (mImageCache != null) {
mImageCache.initDiskCache();
}
}
protected void clearCacheInternal() {
if (mImageCache != null) {
mImageCache.clearCache();
}
}
protected void flushCacheInternal() {
if (mImageCache != null) {
mImageCache.flush();
}
}
protected void closeCacheInternal() {
if (mImageCache != null) {
mImageCache.close();
mImageCache = null;
}
}
public void clearCache() {
new CacheAsyncTask().execute(MESSAGE_CLEAR);
}
public void flushCache() {
new CacheAsyncTask().execute(MESSAGE_FLUSH);
}
public void closeCache() {
new CacheAsyncTask().execute(MESSAGE_CLOSE);
}
}

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/*
* Copyright (C) 2013 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import android.content.res.Resources;
import android.graphics.Bitmap;
import android.graphics.drawable.BitmapDrawable;
import com.example.android.common.logger.Log;
import com.example.android.displayingbitmaps.BuildConfig;
/**
* A BitmapDrawable that keeps track of whether it is being displayed or cached.
* When the drawable is no longer being displayed or cached,
* {@link android.graphics.Bitmap#recycle() recycle()} will be called on this drawable's bitmap.
*/
public class RecyclingBitmapDrawable extends BitmapDrawable {
static final String TAG = "CountingBitmapDrawable";
private int mCacheRefCount = 0;
private int mDisplayRefCount = 0;
private boolean mHasBeenDisplayed;
public RecyclingBitmapDrawable(Resources res, Bitmap bitmap) {
super(res, bitmap);
}
/**
* Notify the drawable that the displayed state has changed. Internally a
* count is kept so that the drawable knows when it is no longer being
* displayed.
*
* @param isDisplayed - Whether the drawable is being displayed or not
*/
public void setIsDisplayed(boolean isDisplayed) {
//BEGIN_INCLUDE(set_is_displayed)
synchronized (this) {
if (isDisplayed) {
mDisplayRefCount++;
mHasBeenDisplayed = true;
} else {
mDisplayRefCount--;
}
}
// Check to see if recycle() can be called
checkState();
//END_INCLUDE(set_is_displayed)
}
/**
* Notify the drawable that the cache state has changed. Internally a count
* is kept so that the drawable knows when it is no longer being cached.
*
* @param isCached - Whether the drawable is being cached or not
*/
public void setIsCached(boolean isCached) {
//BEGIN_INCLUDE(set_is_cached)
synchronized (this) {
if (isCached) {
mCacheRefCount++;
} else {
mCacheRefCount--;
}
}
// Check to see if recycle() can be called
checkState();
//END_INCLUDE(set_is_cached)
}
private synchronized void checkState() {
//BEGIN_INCLUDE(check_state)
// If the drawable cache and display ref counts = 0, and this drawable
// has been displayed, then recycle
if (mCacheRefCount <= 0 && mDisplayRefCount <= 0 && mHasBeenDisplayed
&& hasValidBitmap()) {
if (BuildConfig.DEBUG) {
Log.d(TAG, "No longer being used or cached so recycling. "
+ toString());
}
getBitmap().recycle();
}
//END_INCLUDE(check_state)
}
private synchronized boolean hasValidBitmap() {
Bitmap bitmap = getBitmap();
return bitmap != null && !bitmap.isRecycled();
}
}

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/*
* Copyright (C) 2012 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package com.example.android.displayingbitmaps.util;
import android.annotation.TargetApi;
import android.os.Build;
import android.os.Build.VERSION_CODES;
import android.os.StrictMode;
import com.example.android.displayingbitmaps.ui.ImageDetailActivity;
import com.example.android.displayingbitmaps.ui.ImageGridActivity;
/**
* Class containing some static utility methods.
*/
public class Utils {
private Utils() {};
@TargetApi(VERSION_CODES.HONEYCOMB)
public static void enableStrictMode() {
if (Utils.hasGingerbread()) {
StrictMode.ThreadPolicy.Builder threadPolicyBuilder =
new StrictMode.ThreadPolicy.Builder()
.detectAll()
.penaltyLog();
StrictMode.VmPolicy.Builder vmPolicyBuilder =
new StrictMode.VmPolicy.Builder()
.detectAll()
.penaltyLog();
if (Utils.hasHoneycomb()) {
threadPolicyBuilder.penaltyFlashScreen();
vmPolicyBuilder
.setClassInstanceLimit(ImageGridActivity.class, 1)
.setClassInstanceLimit(ImageDetailActivity.class, 1);
}
StrictMode.setThreadPolicy(threadPolicyBuilder.build());
StrictMode.setVmPolicy(vmPolicyBuilder.build());
}
}
public static boolean hasFroyo() {
// Can use static final constants like FROYO, declared in later versions
// of the OS since they are inlined at compile time. This is guaranteed behavior.
return Build.VERSION.SDK_INT >= VERSION_CODES.FROYO;
}
public static boolean hasGingerbread() {
return Build.VERSION.SDK_INT >= VERSION_CODES.GINGERBREAD;
}
public static boolean hasHoneycomb() {
return Build.VERSION.SDK_INT >= VERSION_CODES.HONEYCOMB;
}
public static boolean hasHoneycombMR1() {
return Build.VERSION.SDK_INT >= VERSION_CODES.HONEYCOMB_MR1;
}
public static boolean hasJellyBean() {
return Build.VERSION.SDK_INT >= VERSION_CODES.JELLY_BEAN;
}
public static boolean hasKitKat() {
return Build.VERSION.SDK_INT >= VERSION_CODES.KITKAT;
}
}