Question

I want to code an app that displays some information in an widget, which should be updated from time to time. From time to time means, that I use an alarm timer to trigger a peroidic update. So heres the problem: intent.getIntArrayExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS); is null for the broadcast receivers intent.

Here’s my widget provider:

public class MyWidgetProvider extends AppWidgetProvider {
    public void onUpdate(Context context, AppWidgetManager appWidgetManager, int[] appWidgetIds) {
        final int N = appWidgetIds.length;      
    for(int i=0; i<N; i++) {
            int widgetId = appWidgetIds[i];         
            RemoteViews rViews = new RemoteViews(context.getPackageName(), R.layout.widget_layout);         
            Intent intent = new Intent(context.getApplicationContext(), TrafficService.class);
            intent.putExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS, appWidgetIds);            
            rViews.setTextViewText(R.id.TextView01, "" + System.currentTimeMillis());           
            appWidgetManager.updateAppWidget(widgetId, rViews);
        }
    }
}

and this is the BroadcastReceiver causing the problem:

public class TimeIntervalReceiver extends BroadcastReceiver {
    @Override
    public void onReceive(Context context, Intent intent) {
// set new alarm timer (code cut out)       
        AppWidgetManager appWidgetManager = AppWidgetManager.getInstance(context.getApplicationContext());
        // PROBLEM BELOW!
        int[] appWidgetIds = intent.getIntArrayExtra(AppWidgetManager.EXTRA_APPWIDGET_IDS);     
        if(appWidgetIds == null) Log.d("TRAFFIC", "oh SHIT");
        if(appWidgetIds != null && appWidgetIds.length > 0) {
            for(int widgetId : appWidgetIds) {
                RemoteViews rViews = new RemoteViews(context.getPackageName(), R.layout.widget_layout);
                rViews.setTextViewText(R.id.TextView01, "some data");
                appWidgetManager.updateAppWidget(widgetId, rViews);
            }
        }
    }
}

Is this even solveable?

Answer 1

When the system calls your implementation of AppWidgetProvider, it fills the intent with these extras.

But when it calls your broadcast receiver which has nothing to do with the widget, it does not fill this extra in the intent.

You will have to use another method to transfer the ID’s. Maybe you could fill them in the Intent which is fired as the alarm fires?