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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 BroadcastReceiver. AppWidgetProvider merely parses the relevant fields out of the Intent that is received in onReceive(Context,Intent), and calls hook methods with the received extras. 
Extend this class and override one or more of the onUpdate, onDeleted, onEnabled or onDisabled methods to implement your own AppWidget functionality. 




Developer Guides


For more information about how to write an app widget provider, read the
App Widgets
developer guide.




/**
 * 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.

/**
     * Constructor to initialize AppWidgetProvider.
     */
    public AppWidgetProvider() {
    }

    
Implements BroadcastReceiver.onReceive to dispatch calls to the various other methods on AppWidgetProvider. 
Params:
  • context – The Context in which the receiver is running.
  • intent – The Intent being received.
/**
     * 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 AppWidgetManager.ACTION_APPWIDGET_UPDATE and AppWidgetManager.ACTION_APPWIDGET_RESTORED broadcasts when this AppWidget provider is being asked to provide RemoteViews for a set of AppWidgets. Override this method to implement your own AppWidget functionality. {@more} 
Params:
  • context –  The Context in which this receiver is running.
  • appWidgetManager – A AppWidgetManager object you can call AppWidgetManager.updateAppWidget on.
  • 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 Also:
/**
     * 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 AppWidgetManager.ACTION_APPWIDGET_OPTIONS_CHANGED broadcast when this widget has been layed out at a new size. {@more} 
Params:
  • context –  The Context in which this receiver is running.
  • appWidgetManager – A AppWidgetManager object you can call AppWidgetManager.updateAppWidget on.
  • appWidgetId – The appWidgetId of the widget whose size changed.
  • newOptions – The appWidgetId of the widget whose size changed.
See Also:
/**
     * 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 AppWidgetManager.ACTION_APPWIDGET_DELETED broadcast when one or more AppWidget instances have been deleted. Override this method to implement your own AppWidget functionality. {@more} 
Params:
  • context –  The Context in which this receiver is running.
  • appWidgetIds – The appWidgetIds that have been deleted from their host.
See Also:
/**
     * 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 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, AppWidgetManager.ACTION_APPWIDGET_DISABLED is sent by the AppWidget manager, and onDisabled is called. If after that, an AppWidget for this provider is created again, onEnabled() will be called again. 
Params:
  • context –  The Context in which this receiver is running.
See Also:
/**
     * 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 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} 
Params:
  • context –  The Context in which this receiver is running.
See Also:
/**
     * 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 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. 
This callback will be followed immediately by a call to onUpdate so your provider can immediately generate new RemoteViews suitable for its newly-restored set of instances. {@more} 
Params:
  • context – 
  • oldWidgetIds – 
  • newWidgetIds – 
/**
     * 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) {
    }
}