am 18159037: Add API demo for game style system UI interaction.

* commit '18159037a4f6a6b539736f6b8c0bdab4d26e3bd7':
  Add API demo for game style system UI interaction.

samples/ApiDemos/AndroidManifest.xml

@@ -2469,6 +2469,16 @@
             </intent-filter>
         </activity>
 
+        <activity android:name=".view.GameActivity"
+                android:label="Views/System UI Visibility/Game"
+                android:theme="@android:style/Theme.Holo.NoActionBar"
+                android:enabled="@bool/atLeastKitKat">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.SAMPLE_CODE" />
+            </intent-filter>
+        </activity>
+
         <activity android:name=".view.Switches" android:label="Views/Switches">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />

samples/ApiDemos/res/layout/game.xml

@@ -0,0 +1,48 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- 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.
+-->
+
+<!-- BEGIN_INCLUDE(complete) -->
+<FrameLayout xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent" android:layout_height="match_parent"
+    >
+    <!-- This is the outer area of the entire game screen, extending out under
+         system UI elements. -->
+    <view class="com.example.android.apis.view.GameActivity$Content"
+        android:id="@+id/content"
+        android:src="@drawable/frantic"
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:scaleType="center"
+        />
+    <!-- This is the inner area of the game, not covered by system UI elements.
+        Any UI elements that need to be accessible when the game is paused or other
+        states where the system UI is shown (such as in menus) should go here. -->
+    <FrameLayout
+        android:layout_width="match_parent"
+        android:layout_height="match_parent"
+        android:fitsSystemWindows="true"
+        android:animateLayoutChanges="true"
+        >
+        <Button
+            android:id="@+id/play"
+            android:layout_width="wrap_content"
+            android:layout_height="wrap_content"
+            android:layout_gravity="top|right"
+            android:textSize="28dp"
+            />
+    </FrameLayout>
+</FrameLayout>
+<!-- END_INCLUDE(complete) -->

samples/ApiDemos/src/com/example/android/apis/graphics/TouchPaint.java

@@ -26,6 +26,7 @@ import android.graphics.RectF;
 import android.os.Bundle;
 import android.os.Handler;
 import android.os.Message;
+import android.util.AttributeSet;
 import android.view.Menu;
 import android.view.MenuItem;
 import android.view.MotionEvent;
@@ -87,9 +88,6 @@ public class TouchPaint extends GraphicsActivity {
     /** Is fading mode enabled? */
     boolean mFading;
 
-    /** The index of the current color to use. */
-    int mColorIndex;
-
     @Override
     protected void onCreate(Bundle savedInstanceState) {
         super.onCreate(savedInstanceState);
@@ -104,10 +102,10 @@ public class TouchPaint extends GraphicsActivity {
         // the contents of the bitmap.
         if (savedInstanceState != null) {
             mFading = savedInstanceState.getBoolean("fading", true);
-            mColorIndex = savedInstanceState.getInt("color", 0);
+            mView.mColorIndex = savedInstanceState.getInt("color", 0);
         } else {
             mFading = true;
-            mColorIndex = 0;
+            mView.mColorIndex = 0;
         }
     }
 
@@ -161,7 +159,7 @@ public class TouchPaint extends GraphicsActivity {
         // Save away the fading state to restore if needed later.  Note that
         // we do not currently save the contents of the display.
         outState.putBoolean("fading", mFading);
-        outState.putInt("color", mColorIndex);
+        outState.putInt("color", mView.mColorIndex);
     }
 
     @Override
@@ -225,9 +223,9 @@ public class TouchPaint extends GraphicsActivity {
      *
      * It handles all of the input events and drawing functions.
      */
-    class PaintView extends View {
+    public static class PaintView extends View {
         private static final int FADE_ALPHA = 0x06;
-        private static final int MAX_FADE_STEPS = 256 / FADE_ALPHA + 4;
+        private static final int MAX_FADE_STEPS = 256 / (FADE_ALPHA/2) + 4;
         private static final int TRACKBALL_SCALE = 10;
 
         private static final int SPLAT_VECTORS = 40;
@@ -235,21 +233,31 @@ public class TouchPaint extends GraphicsActivity {
         private final Random mRandom = new Random();
         private Bitmap mBitmap;
         private Canvas mCanvas;
-        private final Paint mPaint;
+        private final Paint mPaint = new Paint();
-        private final Paint mFadePaint;
+        private final Paint mFadePaint = new Paint();
         private float mCurX;
         private float mCurY;
         private int mOldButtonState;
         private int mFadeSteps = MAX_FADE_STEPS;
 
+        /** The index of the current color to use. */
+        int mColorIndex;
+
         public PaintView(Context c) {
             super(c);
+            init();
+        }
+
+        public PaintView(Context c, AttributeSet attrs) {
+            super(c, attrs);
+            init();
+        }
+
+        private void init() {
             setFocusable(true);
 
-            mPaint = new Paint();
             mPaint.setAntiAlias(true);
 
-            mFadePaint = new Paint();
             mFadePaint.setColor(BACKGROUND_COLOR);
             mFadePaint.setAlpha(FADE_ALPHA);
         }
@@ -273,6 +281,31 @@ public class TouchPaint extends GraphicsActivity {
             }
         }
 
+        public void text(String text) {
+            if (mBitmap != null) {
+                final int width = mBitmap.getWidth();
+                final int height = mBitmap.getHeight();
+                mPaint.setColor(COLORS[mColorIndex]);
+                mPaint.setAlpha(255);
+                int size = height;
+                mPaint.setTextSize(size);
+                Rect bounds = new Rect();
+                mPaint.getTextBounds(text, 0, text.length(), bounds);
+                int twidth = bounds.width();
+                twidth += (twidth/4);
+                if (twidth > width) {
+                    size = (size*width)/twidth;
+                    mPaint.setTextSize(size);
+                    mPaint.getTextBounds(text, 0, text.length(), bounds);
+                }
+                Paint.FontMetrics fm = mPaint.getFontMetrics();
+                mCanvas.drawText(text, (width-bounds.width())/2,
+                        ((height-size)/2) - fm.ascent, mPaint);
+                mFadeSteps = 0;
+                invalidate();
+            }
+        }
+
         @Override
         protected void onSizeChanged(int w, int h, int oldw, int oldh) {
             int curW = mBitmap != null ? mBitmap.getWidth() : 0;

samples/ApiDemos/src/com/example/android/apis/view/GameActivity.java

@@ -0,0 +1,189 @@
+/*
+ * 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.apis.view;
+
+import android.app.ActionBar;
+import android.app.ActionBar.Tab;
+import android.app.Activity;
+import android.app.FragmentTransaction;
+import android.content.Context;
+import android.content.Intent;
+import android.net.Uri;
+import android.os.Bundle;
+import android.os.Handler;
+import android.util.AttributeSet;
+import android.util.Log;
+import android.view.Menu;
+import android.view.MenuInflater;
+import android.view.MenuItem;
+import android.view.View;
+import android.view.Window;
+import android.widget.Button;
+import android.widget.ImageView;
+import android.widget.SearchView;
+import android.widget.SeekBar;
+import android.widget.ShareActionProvider;
+import android.widget.TextView;
+import android.widget.Toast;
+import android.widget.SearchView.OnQueryTextListener;
+
+import com.example.android.apis.R;
+import com.example.android.apis.graphics.TouchPaint;
+
+/**
+ * This activity demonstrates how to use the system UI flags to
+ * implement an immersive game.
+ */
+public class GameActivity extends Activity {
+
+    /**
+     * Implementation of a view for the game, filling the entire screen.
+     */
+//BEGIN_INCLUDE(content)
+    public static class Content extends TouchPaint.PaintView implements
+            View.OnSystemUiVisibilityChangeListener, View.OnClickListener {
+        Activity mActivity;
+        Button mPlayButton;
+        boolean mPaused;
+        int mLastSystemUiVis;
+        boolean mUpdateSystemUi;
+
+        Runnable mFader = new Runnable() {
+            @Override public void run() {
+                fade();
+                if (mUpdateSystemUi) {
+                    updateNavVisibility();
+                }
+                if (!mPaused) {
+                    getHandler().postDelayed(mFader, 1000/30);
+                }
+            }
+        };
+
+        public Content(Context context, AttributeSet attrs) {
+            super(context, attrs);
+            setOnSystemUiVisibilityChangeListener(this);
+        }
+
+        public void init(Activity activity, Button playButton) {
+            // This called by the containing activity to supply the surrounding
+            // state of the game that it will interact with.
+            mActivity = activity;
+            mPlayButton = playButton;
+            mPlayButton.setOnClickListener(this);
+            setGamePaused(true);
+        }
+
+        @Override public void onSystemUiVisibilityChange(int visibility) {
+            // Detect when we go out of nav-hidden mode, to reset back to having
+            // it hidden; our game wants those elements to stay hidden as long
+            // as it is being played and stay shown when paused.
+            int diff = mLastSystemUiVis ^ visibility;
+            mLastSystemUiVis = visibility;
+            if (!mPaused && (diff&SYSTEM_UI_FLAG_HIDE_NAVIGATION) != 0
+                    && (visibility&SYSTEM_UI_FLAG_HIDE_NAVIGATION) == 0) {
+                // We are running and the system UI navigation has become
+                // shown...  we want it to remain hidden, so update our system
+                // UI state at the next game loop.
+                mUpdateSystemUi = true;
+            }
+        }
+
+        @Override protected void onWindowVisibilityChanged(int visibility) {
+            super.onWindowVisibilityChanged(visibility);
+
+            // When we become visible or invisible, play is paused.
+            setGamePaused(true);
+        }
+
+        @Override
+        public void onWindowFocusChanged(boolean hasWindowFocus) {
+            super.onWindowFocusChanged(hasWindowFocus);
+
+            // When we become visible or invisible, play is paused.
+            // Optional: pause game when window loses focus.  This will cause it to
+            // pause, for example, when the notification shade is pulled down.
+            if (!hasWindowFocus) {
+                //setGamePaused(true);
+            }
+        }
+
+        @Override public void onClick(View v) {
+            if (v == mPlayButton) {
+                // Clicking on the play/pause button toggles its state.
+                setGamePaused(!mPaused);
+            }
+        }
+
+        void setGamePaused(boolean paused) {
+            mPaused = paused;
+            mPlayButton.setText(paused ? R.string.play : R.string.pause);
+            setKeepScreenOn(!paused);
+            updateNavVisibility();
+            Handler h = getHandler();
+            if (h != null) {
+                getHandler().removeCallbacks(mFader);
+                if (!paused) {
+                    mFader.run();
+                    text("Draw!");
+                }
+            }
+        }
+
+        void updateNavVisibility() {
+            int newVis = SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
+                    | SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
+                    | SYSTEM_UI_FLAG_LAYOUT_STABLE;
+            if (!mPaused) {
+                newVis |= SYSTEM_UI_FLAG_LOW_PROFILE | SYSTEM_UI_FLAG_FULLSCREEN
+                        | SYSTEM_UI_FLAG_HIDE_NAVIGATION  | SYSTEM_UI_FLAG_IMMERSIVE_STICKY;
+            }
+
+            // Set the new desired visibility.
+            setSystemUiVisibility(newVis);
+            mUpdateSystemUi = false;
+        }
+    }
+//END_INCLUDE(content)
+
+    Content mContent;
+
+    public GameActivity() {
+    }
+
+    @Override
+    public void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        setContentView(R.layout.game);
+        mContent = (Content)findViewById(R.id.content);
+        mContent.init(this, (Button)findViewById(R.id.play));
+    }
+
+    @Override
+    public void onAttachedToWindow() {
+        super.onAttachedToWindow();
+    }
+
+    @Override
+    protected void onPause() {
+        super.onPause();
+
+        // Pause game when its activity is paused.
+        mContent.setGamePaused(true);
+    }
+}