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        }
70        else if (AppWidgetManager.ACTION_APPWIDGET_DELETED.equals(action)) {
71            Bundle extras = intent.getExtras();
72            if (extras != null && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_ID)) {
73                final int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID);
74                this.onDeleted(context, new int[] { appWidgetId });
75            }
76        }
77        else if (AppWidgetManager.ACTION_APPWIDGET_OPTIONS_CHANGED.equals(action)) {
78            Bundle extras = intent.getExtras();
79            if (extras != null && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_ID)
80                    && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_OPTIONS)) {
81                int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID);
82                Bundle widgetExtras = extras.getBundle(AppWidgetManager.EXTRA_APPWIDGET_OPTIONS);
83                this.onAppWidgetOptionsChanged(context, AppWidgetManager.getInstance(context),
84                        appWidgetId, widgetExtras);
85            }
86        }
87        else if (AppWidgetManager.ACTION_APPWIDGET_ENABLED.equals(action)) {
88            this.onEnabled(context);
89        }
90        else if (AppWidgetManager.ACTION_APPWIDGET_DISABLED.equals(action)) {
91            this.onDisabled(context);
92        }
93    }
94    // END_INCLUDE(onReceive)
95
96    /**
97     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_UPDATE} broadcast when
98     * this AppWidget provider is being asked to provide {@link android.widget.RemoteViews RemoteViews}
99     * for a set of AppWidgets.  Override this method to implement your own AppWidget functionality.
100     *
101     * {@more}
102     *
103     * @param context   The {@link android.content.Context Context} in which this receiver is
104     *                  running.
105     * @param appWidgetManager A {@link AppWidgetManager} object you can call {@link
106     *                  AppWidgetManager#updateAppWidget} on.
107     * @param appWidgetIds The appWidgetIds for which an update is needed.  Note that this
108     *                  may be all of the AppWidget instances for this provider, or just
109     *                  a subset of them.
110     *
111     * @see AppWidgetManager#ACTION_APPWIDGET_UPDATE
112     */
113    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
114    }
115
116    /**
117     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_OPTIONS_CHANGED}
118     * broadcast when this widget has been layed out at a new size.
119     *
120     * {@more}
121     *
122     * @param context   The {@link android.content.Context Context} in which this receiver is
123     *                  running.
124     * @param appWidgetManager A {@link AppWidgetManager} object you can call {@link
125     *                  AppWidgetManager#updateAppWidget} on.
126     * @param appWidgetId The appWidgetId of the widget who's size changed.
127     * @param newOptions The appWidgetId of the widget who's size changed.
128     *
129     * @see AppWidgetManager#ACTION_APPWIDGET_OPTIONS_CHANGED
130     */
131    public void onAppWidgetOptionsChanged(Context context, AppWidgetManager appWidgetManager,
132            int appWidgetId, Bundle newOptions) {
133    }
134
135    /**
136     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_DELETED} broadcast when
137     * one or more AppWidget instances have been deleted.  Override this method to implement
138     * your own AppWidget functionality.
139     *
140     * {@more}
141     *
142     * @param context   The {@link android.content.Context Context} in which this receiver is
143     *                  running.
144     * @param appWidgetIds The appWidgetIds that have been deleted from their host.
145     *
146     * @see AppWidgetManager#ACTION_APPWIDGET_DELETED
147     */
148    public void onDeleted(Context context, int[] appWidgetIds) {
149    }
150
151    /**
152     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_ENABLED} broadcast when
153     * the a AppWidget for this provider is instantiated.  Override this method to implement your
154     * own AppWidget functionality.
155     *
156     * {@more}
157     * When the last AppWidget for this provider is deleted,
158     * {@link AppWidgetManager#ACTION_APPWIDGET_DISABLED} is sent by the AppWidget manager, and
159     * {@link #onDisabled} is called.  If after that, an AppWidget for this provider is created
160     * again, onEnabled() will be called again.
161     *
162     * @param context   The {@link android.content.Context Context} in which this receiver is
163     *                  running.
164     *
165     * @see AppWidgetManager#ACTION_APPWIDGET_ENABLED
166     */
167    public void onEnabled(Context context) {
168    }
169
170    /**
171     * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_DISABLED} broadcast, which
172     * is sent when the last AppWidget instance for this provider is deleted.  Override this method
173     * to implement your own AppWidget functionality.
174     *
175     * {@more}
176     *
177     * @param context   The {@link android.content.Context Context} in which this receiver is
178     *                  running.
179     *
180     * @see AppWidgetManager#ACTION_APPWIDGET_DISABLED
181     */
182    public void onDisabled(Context context) {
183    }
184}
185