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/* * Copyright (C) 2006 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 android.appwidget; import android.content.BroadcastReceiver; import android.content.Context; import android.content.Intent; import android.os.Bundle; /** * A convenience class to aid in implementing an AppWidget provider. * Everything you can do with AppWidgetProvider, you can do with a regular {@link BroadcastReceiver}. * AppWidgetProvider merely parses the relevant fields out of the Intent that is received in * {@link #onReceive(Context,Intent) onReceive(Context,Intent)}, and calls hook methods * with the received extras. * * <p>Extend this class and override one or more of the {@link #onUpdate}, {@link #onDeleted}, * {@link #onEnabled} or {@link #onDisabled} methods to implement your own AppWidget functionality. * </p> * * <div class="special reference"> * <h3>Developer Guides</h3> * <p>For more information about how to write an app widget provider, read the * <a href="{@docRoot}guide/topics/appwidgets/index.html#AppWidgetProvider">App Widgets</a> * developer guide.</p> * </div> */ public class AppWidgetProvider extends BroadcastReceiver { /** * Constructor to initialize AppWidgetProvider. */ public AppWidgetProvider() { } /** * Implements {@link BroadcastReceiver#onReceive} to dispatch calls to the various * other methods on AppWidgetProvider. * * @param context The Context in which the receiver is running. * @param intent The Intent being received. */ // BEGIN_INCLUDE(onReceive) public void onReceive(Context context, Intent intent) { // Protect against rogue update broadcasts (not really a security issue, // just filter bad broacasts out so subclasses are less likely to crash). String action = intent.getAction(); if (AppWidgetManager.ACTION_APPWIDGET_UPDATE.equals(action)) { Bundle extras = intent.getExtras(); if (extras != null) { int[] appWidgetIds = extras.getIntArray(AppWidgetManager.EXTRA_APPWIDGET_IDS); if (appWidgetIds != null && appWidgetIds.length > 0) { this.onUpdate(context, AppWidgetManager.getInstance(context), appWidgetIds); } } } else if (AppWidgetManager.ACTION_APPWIDGET_DELETED.equals(action)) { Bundle extras = intent.getExtras(); if (extras != null && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_ID)) { final int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID); this.onDeleted(context, new int[] { appWidgetId }); } } else if (AppWidgetManager.ACTION_APPWIDGET_OPTIONS_CHANGED.equals(action)) { Bundle extras = intent.getExtras(); if (extras != null && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_ID) && extras.containsKey(AppWidgetManager.EXTRA_APPWIDGET_OPTIONS)) { int appWidgetId = extras.getInt(AppWidgetManager.EXTRA_APPWIDGET_ID); Bundle widgetExtras = extras.getBundle(AppWidgetManager.EXTRA_APPWIDGET_OPTIONS); this.onAppWidgetOptionsChanged(context, AppWidgetManager.getInstance(context), appWidgetId, widgetExtras); } } else if (AppWidgetManager.ACTION_APPWIDGET_ENABLED.equals(action)) { this.onEnabled(context); } else if (AppWidgetManager.ACTION_APPWIDGET_DISABLED.equals(action)) { this.onDisabled(context); } else if (AppWidgetManager.ACTION_APPWIDGET_RESTORED.equals(action)) { Bundle extras = intent.getExtras(); if (extras != null) { int[] oldIds = extras.getIntArray(AppWidgetManager.EXTRA_APPWIDGET_OLD_IDS); int[] newIds = extras.getIntArray(AppWidgetManager.EXTRA_APPWIDGET_IDS); if (oldIds != null && oldIds.length > 0) { this.onRestored(context, oldIds, newIds); this.onUpdate(context, AppWidgetManager.getInstance(context), newIds); } } } } // END_INCLUDE(onReceive) /** * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_UPDATE} and * {@link AppWidgetManager#ACTION_APPWIDGET_RESTORED} broadcasts when this AppWidget * provider is being asked to provide {@link android.widget.RemoteViews RemoteViews} * for a set of AppWidgets. Override this method to implement your own AppWidget functionality. * * {@more} * * @param context The {@link android.content.Context Context} in which this receiver is * running. * @param appWidgetManager A {@link AppWidgetManager} object you can call {@link * AppWidgetManager#updateAppWidget} on. * @param appWidgetIds The appWidgetIds for which an update is needed. Note that this * may be all of the AppWidget instances for this provider, or just * a subset of them. * * @see AppWidgetManager#ACTION_APPWIDGET_UPDATE */ public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) { } /** * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_OPTIONS_CHANGED} * broadcast when this widget has been layed out at a new size. * * {@more} * * @param context The {@link android.content.Context Context} in which this receiver is * running. * @param appWidgetManager A {@link AppWidgetManager} object you can call {@link * AppWidgetManager#updateAppWidget} on. * @param appWidgetId The appWidgetId of the widget whose size changed. * @param newOptions The appWidgetId of the widget whose size changed. * * @see AppWidgetManager#ACTION_APPWIDGET_OPTIONS_CHANGED */ public void onAppWidgetOptionsChanged(Context context, AppWidgetManager appWidgetManager, int appWidgetId, Bundle newOptions) { } /** * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_DELETED} broadcast when * one or more AppWidget instances have been deleted. Override this method to implement * your own AppWidget functionality. * * {@more} * * @param context The {@link android.content.Context Context} in which this receiver is * running. * @param appWidgetIds The appWidgetIds that have been deleted from their host. * * @see AppWidgetManager#ACTION_APPWIDGET_DELETED */ public void onDeleted(Context context, int[] appWidgetIds) { } /** * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_ENABLED} broadcast when * the a AppWidget for this provider is instantiated. Override this method to implement your * own AppWidget functionality. * * {@more} * When the last AppWidget for this provider is deleted, * {@link AppWidgetManager#ACTION_APPWIDGET_DISABLED} is sent by the AppWidget manager, and * {@link #onDisabled} is called. If after that, an AppWidget for this provider is created * again, onEnabled() will be called again. * * @param context The {@link android.content.Context Context} in which this receiver is * running. * * @see AppWidgetManager#ACTION_APPWIDGET_ENABLED */ public void onEnabled(Context context) { } /** * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_DISABLED} broadcast, which * is sent when the last AppWidget instance for this provider is deleted. Override this method * to implement your own AppWidget functionality. * * {@more} * * @param context The {@link android.content.Context Context} in which this receiver is * running. * * @see AppWidgetManager#ACTION_APPWIDGET_DISABLED */ public void onDisabled(Context context) { } /** * Called in response to the {@link AppWidgetManager#ACTION_APPWIDGET_RESTORED} broadcast * when instances of this AppWidget provider have been restored from backup. If your * provider maintains any persistent data about its widget instances, override this method * to remap the old AppWidgetIds to the new values and update any other app state that may * be relevant. * * <p>This callback will be followed immediately by a call to {@link #onUpdate} so your * provider can immediately generate new RemoteViews suitable for its newly-restored set * of instances. * * {@more} * * @param context * @param oldWidgetIds * @param newWidgetIds */ public void onRestored(Context context, int[] oldWidgetIds, int[] newWidgetIds) { } }