Question

I’m trying to create my first AppWidget using the AlarmManager class so that I can update more frequently than every 30 minutes. I followed this tutorial as a basis for setting up my widget, but for some reason I cannot get the updates to begin properly. It appears as I am never receiving any APPWIDGET_ENABLED intents, which would fire off the onEnabled event callback in my AppWidgetProvider.

Here is the manifest definition for my AppWidgetProvider:

    <receiver 
       android:name="com.myapp.android.appwidget.MarketTimingAppWidgetProvider"
       android:label="@string/appwidget_markettiming_label">
        <intent-filter>
            <action android:name="android.appwidget.action.APPWIDGET_UPDATE" /> 
            <action android:name="@string/appwidget_markettiming_updateintent" />           
        </intent-filter>
        <meta-data android:name="android.appwidget.provider"
                   android:resource="@xml/appwidget_markettiming_info" />
    </receiver>

Here is the code for my AppWidgetProvider:

public class MarketTimingAppWidgetProvider extends AppWidgetProvider {

public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {

    final int N = appWidgetIds.length;

    Log.d("myLogger", "onUpdate");
    // Perform this loop procedure for each App Widget that belongs to this provider
    for (int i=0; i<N; i++) {

        int appWidgetId = appWidgetIds[i];
        Log.d("myLogger", "Updating Widget: " + appWidgetId);
        updateWidget(context, appWidgetManager, appWidgetId);

    }

}

@Override
public void onEnabled(Context context) {
    super.onEnabled(context);

    Log.d("myLogger", "onEnabled running");
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    Calendar calendar = Calendar.getInstance();
    calendar.setTimeInMillis(System.currentTimeMillis());
    calendar.add(Calendar.SECOND, 1);
    alarmManager.setRepeating(AlarmManager.RTC, calendar.getTimeInMillis(), 
                              1000, createClockIntent(context));   
}

public void onDisabled(Context context) {
    super.onDisabled(context);
    AlarmManager alarmManager = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);
    alarmManager.cancel(createClockIntent(context));
}

public void onReceive(Context context, Intent intent) {
    super.onReceive(context, intent);

    Log.d("myLogger", "Intent Received " + intent.getAction());
    String widgetIntent = context.getResources().getString(R.string.appwidget_markettiming_updateintent);

    // This code fires when my custom intent is received
    if(widgetIntent.equals(intent.getAction())) {
        ComponentName thisAppWidget = new ComponentName(context.getPackageName(), getClass().getName());
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context);
        int ids[] = appWidgetManager.getAppWidgetIds(thisAppWidget);
        for(int appWidgetId: ids) {
            updateWidget(context, appWidgetManager, appWidgetId);
        }
    }

}

private void updateWidget(Context context, AppWidgetManager appWidgetManager, int appWidgetId) {

    RemoteViews views = new RemoteViews(context.getPackageName(), R.layout.appwidget_markettiming);
    views.setTextViewText(R.id.widget_text, "Update: " +  
            DateFormat.getDateTimeInstance(
                    DateFormat.LONG, DateFormat.LONG).format(new Date()));

    // Tell the AppWidgetManager to perform an update on the current app widget
    appWidgetManager.updateAppWidget(appWidgetId, views);

}

private PendingIntent createClockIntent(Context context) {
    String updateIntent = context.getResources().getString(R.string.appwidget_markettiming_updateintent);
    Log.d("myLogger", "my intent: " + updateIntent);
    Intent intent = new Intent(updateIntent);
    PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0, intent, PendingIntent.FLAG_UPDATE_CURRENT);
    return pendingIntent;
}

}

When I look in LogCat the only intent that is ever recieved by my onReceive method is the initial APPWIDGET_UPDATE intent, and the only callback ever executed is the onUpdate callback. I’ve tried including the APPWIDGET_ENABLED intent in my appwidget intent-filter (although the docs tell me that this should be automatically received by my widget). It didn’t work. Is there just something I’m missing here?

Answer 1

There is an error in your manifest. Action name in this element:

<action android:name="@string/appwidget_markettiming_updateintent" />

should be replaced by actual string, not the reference. So it should be something like this:

<action android:name="com.myapp.android.appwidget.action.MARKETTIMING_UPDATE" />

or whatever you have in your values/something.xml inside the <string name="appwidget_markettiming_updateintent"> element.

The problem is that the BroadcastReceiver does not receives the broadcasts from AlarmManager. I’ve created a project with your code, replaced only this string in manifest (and added the appropriate value to values/strings.xml of course) and all works fine.

In addition, you may want to replace the second parameter of alarmManager.setRepeating() by just System.currentTimeMillis() + 1000 and remove all those extra Calendar-related stuff.