1/*
2 * Copyright (C) 2006 The Android Open Source Project
3 *
4 * Licensed under the Apache License, Version 2.0 (the "License");
5 * you may not use this file except in compliance with the License.
6 * You may obtain a copy of the License at
7 *
8 *      http://www.apache.org/licenses/LICENSE-2.0
9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17package android.appwidget;
18
19import android.content.BroadcastReceiver;
20import android.content.Context;
21import android.content.Intent;
22import android.os.Bundle;
23
24/**
25 * A convenience class to aid in implementing an AppWidget provider.
26 * Everything you can do with AppWidgetProvider, you can do with a regular {@link BroadcastReceiver}.
27 * AppWidgetProvider merely parses the relevant fields out of the Intent that is received in
28 * {@link #onReceive(Context,Intent) onReceive(Context,Intent)}, and calls hook methods
29 * with the received extras.
30 *
31 * <p>Extend this class and override one or more of the {@link #onUpdate}, {@link #onDeleted},
32 * {@link #onEnabled} or {@link #onDisabled} methods to implement your own AppWidget functionality.
33 * </p>
34 *
35 * <div class="special reference">
36 * <h3>Developer Guides</h3>
37 * <p>For more information about how to write an app widget provider, read the
38 * <a href="{@docRoot}guide/topics/appwidgets/index.html#AppWidgetProvider">App Widgets</a>
39 * developer guide.</p>
40 * </div>
41 */
42public class AppWidgetProvider extends BroadcastReceiver {
43    /**
44     * Constructor to initialize AppWidgetProvider.
45     */
46    public AppWidgetProvider() {
47    }
48
49    /**
50     * Implements {@link BroadcastReceiver#onReceive} to dispatch calls to the various
51     * other methods on AppWidgetProvider.
52     *
53     * @param context The Context in which the receiver is running.
54     * @param intent The Intent being received.
55     */
56    // BEGIN_INCLUDE(onReceive)
57    public void onReceive(Context context, Intent intent) {
58        // Protect against rogue update broadcasts (not really a security issue,
59        // just filter bad broacasts out so subclasses are less likely to crash).
60        String action = intent.getAction();
61        if (AppWidgetManager.ACTION_APPWIDGET_UPDATE.equals(action)) {
62            Bundle extras = intent.getExtras();
63            if (extras != null) {
64                int[] appWidgetIds = extras.getIntArray(AppWidgetManager.EXTRA_APPWIDGET_IDS);
65                if (appWidgetIds != null && appWidgetIds.length > 0) {
66                    this.onUpdate(context, AppWidgetManager.getInstance(context), appWidgetIds);
67                }
68            }
69        } else if (AppWidgetManager.ACTION_APPWIDGET_DELETED.equals(action)) {
70            Bundle extras = intent.getExtras();
71            if (extras != null && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_ID)) {
72                final int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID);
73                this.onDeleted(context, new int[] { appWidgetId });
74            }
75        } else if (AppWidgetManager.ACTION_APPWIDGET_OPTIONS_CHANGED.equals(action)) {
76            Bundle extras = intent.getExtras();
77            if (extras != null && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_ID)
78                    && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_OPTIONS)) {
79                int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID);
80                Bundle widgetExtras = extras.getBundle(AppWidgetManager.EXTRA_APPWIDGET_OPTIONS);
81                this.onAppWidgetOptionsChanged(context, AppWidgetManager.getInstance(context),
82                        appWidgetId, widgetExtras);
83            }
84        } else if (AppWidgetManager.ACTION_APPWIDGET_ENABLED.equals(action)) {
85            this.onEnabled(context);
86        } else if (AppWidgetManager.ACTION_APPWIDGET_DISABLED.equals(action)) {
87            this.onDisabled(context);
88        } else if (AppWidgetManager.ACTION_APPWIDGET_RESTORED.equals(action)) {
89            Bundle extras = intent.getExtras();
90            if (extras != null) {
91                int[] oldIds = extras.getIntArray(AppWidgetManager.EXTRA_APPWIDGET_OLD_IDS);
92                int[] newIds = extras.getIntArray(AppWidgetManager.EXTRA_APPWIDGET_IDS);
93                if (oldIds != null && oldIds.length > 0) {
94                    this.onRestored(context, oldIds, newIds);
95                    this.onUpdate(context, AppWidgetManager.getInstance(context), newIds);
96                }
97            }
98        }
99    }
100    // END_INCLUDE(onReceive)
101
102    /**
103     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_UPDATE} and
104     * {@link AppWidgetManager#ACTION_APPWIDGET_RESTORED} broadcasts when this AppWidget
105     * provider is being asked to provide {@link android.widget.RemoteViews RemoteViews}
106     * for a set of AppWidgets.  Override this method to implement your own AppWidget functionality.
107     *
108     * {@more}
109     *
110     * @param context   The {@link android.content.Context Context} in which this receiver is
111     *                  running.
112     * @param appWidgetManager A {@link AppWidgetManager} object you can call {@link
113     *                  AppWidgetManager#updateAppWidget} on.
114     * @param appWidgetIds The appWidgetIds for which an update is needed.  Note that this
115     *                  may be all of the AppWidget instances for this provider, or just
116     *                  a subset of them.
117     *
118     * @see AppWidgetManager#ACTION_APPWIDGET_UPDATE
119     */
120    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
121    }
122
123    /**
124     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_OPTIONS_CHANGED}
125     * broadcast when this widget has been layed out at a new size.
126     *
127     * {@more}
128     *
129     * @param context   The {@link android.content.Context Context} in which this receiver is
130     *                  running.
131     * @param appWidgetManager A {@link AppWidgetManager} object you can call {@link
132     *                  AppWidgetManager#updateAppWidget} on.
133     * @param appWidgetId The appWidgetId of the widget whose size changed.
134     * @param newOptions The appWidgetId of the widget whose size changed.
135     *
136     * @see AppWidgetManager#ACTION_APPWIDGET_OPTIONS_CHANGED
137     */
138    public void onAppWidgetOptionsChanged(Context context, AppWidgetManager appWidgetManager,
139            int appWidgetId, Bundle newOptions) {
140    }
141
142    /**
143     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_DELETED} broadcast when
144     * one or more AppWidget instances have been deleted.  Override this method to implement
145     * your own AppWidget functionality.
146     *
147     * {@more}
148     *
149     * @param context   The {@link android.content.Context Context} in which this receiver is
150     *                  running.
151     * @param appWidgetIds The appWidgetIds that have been deleted from their host.
152     *
153     * @see AppWidgetManager#ACTION_APPWIDGET_DELETED
154     */
155    public void onDeleted(Context context, int[] appWidgetIds) {
156    }
157
158    /**
159     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_ENABLED} broadcast when
160     * the a AppWidget for this provider is instantiated.  Override this method to implement your
161     * own AppWidget functionality.
162     *
163     * {@more}
164     * When the last AppWidget for this provider is deleted,
165     * {@link AppWidgetManager#ACTION_APPWIDGET_DISABLED} is sent by the AppWidget manager, and
166     * {@link #onDisabled} is called.  If after that, an AppWidget for this provider is created
167     * again, onEnabled() will be called again.
168     *
169     * @param context   The {@link android.content.Context Context} in which this receiver is
170     *                  running.
171     *
172     * @see AppWidgetManager#ACTION_APPWIDGET_ENABLED
173     */
174    public void onEnabled(Context context) {
175    }
176
177    /**
178     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_DISABLED} broadcast, which
179     * is sent when the last AppWidget instance for this provider is deleted.  Override this method
180     * to implement your own AppWidget functionality.
181     *
182     * {@more}
183     *
184     * @param context   The {@link android.content.Context Context} in which this receiver is
185     *                  running.
186     *
187     * @see AppWidgetManager#ACTION_APPWIDGET_DISABLED
188     */
189    public void onDisabled(Context context) {
190    }
191
192    /**
193     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_RESTORED} broadcast
194     * when instances of this AppWidget provider have been restored from backup.  If your
195     * provider maintains any persistent data about its widget instances, override this method
196     * to remap the old AppWidgetIds to the new values and update any other app state that may
197     * be relevant.
198     *
199     * <p>This callback will be followed immediately by a call to {@link #onUpdate} so your
200     * provider can immediately generate new RemoteViews suitable for its newly-restored set
201     * of instances.
202     *
203     * {@more}
204     *
205     * @param context
206     * @param oldWidgetIds
207     * @param newWidgetIds
208     */
209    public void onRestored(Context context, int[] oldWidgetIds, int[] newWidgetIds) {
210    }
211}
212