Android Widget update

Question

Based on this tutorial I created a widget that should show the time. The java way works, but the service way doesn't.

HelloWidget.java:

public class HelloWidget extends AppWidgetProvider {

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

        Intent intent = new Intent(context, UpdateService.class);
        context.startService(intent);
    }
}

UpdateService.java:

public final class UpdateService extends Service {
    @Override
    public void onStart(Intent intent, int startId) {
        RemoteViews updateViews = new RemoteViews(this.getPackageName(), R.layout.main);

        Date date = new Date();
        java.text.DateFormat format = SimpleDateFormat.getTimeInstance(
                SimpleDateFormat.MEDIUM, Locale.getDefault());
                updateViews.setTextViewText(R.id.widget_textview, "Current Time " + format.format(date));

        ComponentName thisWidget = new ComponentName(this, HelloWidget.class);
        AppWidgetManager manager = AppWidgetManager.getInstance(this);
        manager.updateAppWidget(thisWidget, updateViews);
    }

    @Override
    public IBinder onBind(Intent intent) {
        // TODO Auto-generated method stub
        return null;
    }
}

The hello_widget_provider.xml has this row: android:updatePeriodMillis="1000"

Problem:

The widget shows the current time but it's not updating (the java-way is).

My main goal is to update the widget at e.g. 18:56 every day. Idk if this is the good way, but i tried to modify the onUpdate method like below, but it has a problem with ALARM_SERVICE: ALARM_SERVICE cannot be resolved to a variable

public class HelloWidget extends AppWidgetProvider {

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

        AlarmManager alarmManager;
        Intent intent = new Intent(context, AlarmReceiver.class);
        PendingIntent pendingIntent = PendingIntent.getBroadcast(context, 0,
          intent, PendingIntent.FLAG_UPDATE_CURRENT);
        alarmManager = (AlarmManager) getSystemService(ALARM_SERVICE);
        Calendar cal = Calendar.getInstance();
        cal.set(Calendar.HOUR_OF_DAY, 18);
        cal.set(Calendar.MINUTE, 56);
        cal.set(Calendar.SECOND, 0);
        cal.set(Calendar.MILLISECOND, 0);
        alarmManager.setRepeating(AlarmManager.RTC_WAKEUP, cal.getTimeInMillis(), 86400, pendingIntent);
   }
}

Any help is appreciated.

Answer 1

Looking back the time I asked this question makes me realize how much I learned in the past 1,5 years.

Since I have just been working with a widget in the last two weeks and I have just found this unanswered question of mine I decided to solve it. I hope it helps others.

The AppWidgetProvider should look like this:

public class MyWidget extends AppWidgetProvider {

    public static String ACTION_WIDGET_CONFIGURE = "ConfigureWidget";
    public static String ACTION_WIDGET_RECEIVER = "ActionReceiverWidget";
    private PendingIntent service = null;  

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


           final AlarmManager m = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);

           final Calendar TIME = Calendar.getInstance();
           TIME.set(Calendar.MINUTE, 0);
           TIME.set(Calendar.SECOND, 0);
           TIME.set(Calendar.MILLISECOND, 0);

           final Intent i = new Intent(context, MyService.class);

           if (service == null)
           {
               service = PendingIntent.getService(context, 0, i, PendingIntent.FLAG_CANCEL_CURRENT);
           }

           m.setRepeating(AlarmManager.RTC, TIME.getTime().getTime(), 1000 * 1, service);

    }

      @Override
       public void onDeleted(Context context, int[] appWidgetIds) {
               super.onDeleted(context, appWidgetIds);
       }

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

               final AlarmManager m = (AlarmManager) context.getSystemService(Context.ALARM_SERVICE);  
               if (service != null)
               {
                   m.cancel(service);
               }
       }

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

       @Override
       public void onReceive(Context context, Intent intent) {

         super.onReceive(context, intent);

       }

}

The Service:

public class MyService extends Service
{
    @Override
    public void onCreate()
    {
        super.onCreate();
    }

    @Override
    public int onStartCommand(Intent intent, int flags, int startId)
    {
        buildUpdate();

        return super.onStartCommand(intent, flags, startId);
    }

    private void buildUpdate()
    {
        String lastUpdated = DateFormat.format("hh:mm:ss", new Date()).toString();

        RemoteViews view = new RemoteViews(getPackageName(), R.layout.widget_layout);
        view.setTextViewText(R.id.btn_widget, lastUpdated);

        ComponentName thisWidget = new ComponentName(this, MyWidget.class);
        AppWidgetManager manager = AppWidgetManager.getInstance(this);
        manager.updateAppWidget(thisWidget, view);
    }

    @Override
    public IBinder onBind(Intent intent)
    {
        return null;
    }
}

Also, register the provider and the Service in the Manifest:

<receiver android:name="MyWidget" android:label="Tutorial_Widget 1x1">
            <intent-filter>
                <action android:name="android.appwidget.action.APPWIDGET_UPDATE" />
                <action android:name="com.something.MyWidget.ACTION_WIDGET_RECEIVER"/>
            </intent-filter>    
            <meta-data android:name="android.appwidget.provider" android:resource="@xml/widget_info"/>
        </receiver>

         <service android:enabled="true" android:name=".MyService" />

Answer 2

ALARM_SERVICE is a static field of the Context class. So type Context.ALARM_SERVICE or use a static import.

Remember that when you set updatePeriodMillis attribute value it's not guaranteed for your onUpdate method to be called with that period exactly.