New API demo for UndoManager.

Change-Id: Ic49211c771db275f27ceefa5372b005a357fce21

samples/ApiDemos/AndroidManifest.xml

@@ -1117,6 +1117,14 @@
             </intent-filter>
         </activity>
 
+        <activity android:name=".content.TextUndoActivity" android:label="@string/activity_text_undo">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
+                <category android:name="android.intent.category.SAMPLE_CODE" />
+                <category android:name="android.intent.category.EMBED" />
+            </intent-filter>
+        </activity>
+
         <activity android:name=".content.ResourcesLayoutReference"
                 android:label="@string/activity_resources_layout_reference">
             <intent-filter>

samples/ApiDemos/res/layout/text_undo.xml

@@ -0,0 +1,58 @@
+<?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.
+-->
+
+<!-- Demonstrates saving and restoring activity state.
+     See corresponding Java code com.android.sdk.app.SaveRestoreState.java. -->
+
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent" android:layout_height="match_parent">
+    <LinearLayout android:orientation="vertical" android:padding="4dip"
+        android:layout_width="match_parent" android:layout_height="wrap_content">
+
+        <TextView android:id="@+id/msg"
+            android:layout_width="match_parent" android:layout_height="wrap_content"
+            android:layout_weight="0" android:textAppearance="?android:attr/textAppearanceMedium"
+            android:paddingBottom="8dip"
+            android:text="@string/text_undo_msg" />
+
+        <EditText android:id="@+id/text"
+            android:layout_width="match_parent" android:layout_height="wrap_content"
+            android:layout_weight="1"
+            android:textAppearance="?android:attr/textAppearanceMedium"
+            android:freezesText="true">
+        </EditText>
+
+        <LinearLayout
+            android:orientation="horizontal"
+            android:layout_width="wrap_content"
+            android:layout_height="match_parent"
+            android:paddingTop="8dip">
+            <Button
+                android:id="@+id/undo"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="@string/undo"
+                android:layout_gravity="bottom" />
+            <Button
+                android:id="@+id/redo"
+                android:layout_width="wrap_content"
+                android:layout_height="wrap_content"
+                android:text="@string/redo"
+                android:layout_gravity="bottom" />
+        </LinearLayout>
+
+    </LinearLayout>
+</ScrollView>

samples/ApiDemos/res/values/strings.xml

@@ -421,6 +421,12 @@
     <string name="styled_text">Plain, <b>bold</b>, <i>italic</i>, <b><i>bold-italic</i></b></string>
     <string name="styled_text_prog">Assigned programmatically:</string>
 
+    <string name="activity_text_undo">Content/Undo Manager/Text</string>
+    <string name="text_undo_msg">Demonstrates simple use of UndoManager with text editing
+            in a TextView.</string>
+    <string name="undo">Undo</string>
+    <string name="redo">Redo</string>
+
     <string name="activity_resources_layout_reference">Content/Resources/Layout Reference</string>
     <string name="resources_layout_reference_description">Shows how to write layout
         resource references, so that you can define multiple different configurations of

samples/ApiDemos/src/com/example/android/apis/content/TextUndoActivity.java

@@ -0,0 +1,69 @@
+/*
+ * 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.apis.content;
+
+import android.app.Activity;
+import android.content.UndoManager;
+import android.os.Parcelable;
+import android.view.View;
+import android.widget.Button;
+import com.example.android.apis.R;
+
+import android.os.Bundle;
+import android.widget.TextView;
+
+/**
+ * Simple example of using an UndoManager for editing text in a TextView.
+ */
+public class TextUndoActivity extends Activity {
+    UndoManager mUndoManager;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+
+        mUndoManager = new UndoManager();
+        if (savedInstanceState != null) {
+            Parcelable p = savedInstanceState.getParcelable("undo");
+            if (p != null) {
+                mUndoManager.restoreInstanceState(p);
+            }
+        }
+
+        setContentView(R.layout.text_undo);
+
+        ((TextView)findViewById(R.id.text)).setUndoManager(mUndoManager, "text");
+        ((Button)findViewById(R.id.undo)).setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                mUndoManager.undo(null, 1);
+            }
+        });
+        ((Button)findViewById(R.id.redo)).setOnClickListener(new View.OnClickListener() {
+            @Override
+            public void onClick(View v) {
+                mUndoManager.redo(null, 1);
+            }
+        });
+     }
+
+    @Override
+    protected void onSaveInstanceState(Bundle outState) {
+        super.onSaveInstanceState(outState);
+        outState.putParcelable("undo", mUndoManager.saveInstanceState());
+    }
+}