Question

Good day, I have an activity which i navigate to from an icon on an appwidget using pending Intents. Everything is being done in a service class. Now, the activity has a refresh button which when pressed, it sends an intent that calls the onStart() method on the service to update itself and perform some web operations. How do i go about reflecting the changes that could have occurred from the service in the activity without temporarily existing the activity.

Service to Activity:

if(intent.getExtras()!= null){
      appWidgetId = intent.getExtras().getInt(AppWidgetManager.EXTRA_APPWIDGET_ID);

      //if i get this action from my detailedinfo class add a boolean to it

      if(intent.getAction() == refresh_action){

     // boolean variable to hold condition
          my_action = true;
      }



Intent forecast = new Intent(this,detailedInfo.class );
    forecast.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, AppWidgetManager.INVALID_APPWIDGET_ID);
        forecast.putExtra("cityname", city);

 PendingIntent forecastIntent = PendingIntent.getActivity(this, 0, forecast, 0);

        /*onclick to go to detailedInfo class*/
        remoteView.setOnClickPendingIntent(R.id.city_image_id, forecastIntent);


        if(my_action == true){          
            //Log.d(TAG, "my_action is true, performing pending intent");

            try {
                forecastIntent.send(this, 0, forecast);
            } catch (CanceledException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

And in the Activity class:

Intent service = new Intent(this, cityService.class);
        service.putExtra(AppWidgetManager.EXTRA_APPWIDGET_ID, appWidgetId);
        service.setAction(refresh_action);
        Uri data = Uri.withAppendedPath(Uri.parse(CityWidgetProvider.URI_SCHEME + "://widget/id/"), String.valueOf(appWidgetId));
        service.setData(data);
               startService(service);

I tried adding a setAction() method to the intent that calls the service and then use the same pendingIntent(even though i think is a long shot) but they seems to be ignored. Please how do i go about this and what could i have been doing wrong.? As usual any help is highly appreciated. Thank you.

Answer 1

I’m not 100% clear on what you’re trying to do, but the easiest thing to do would be to register a BroadcastReceiver in your Activity onResume (remove it in onPause). When the service is done with whatever it needs to do, broadcast that info.

In the Activity

public static final String ACTION_STRING = "THE_BIG_ACTION";
private BroadcastReceiver receiver = new BroadcastReceiver() {

        @Override
        public void onReceive(Context context, Intent intent) {
            // Do whatever you want here
            Toast.makeText(getApplicationContext(), "received", Toast.LENGTH_SHORT);

        }
    };

    @Override
    protected void onResume() {
        super.onResume();
        registerReceiver(receiver, new IntentFilter(ACTION_STRING));
    }

    @Override
    protected void onPause() {
        super.onPause();
        unregisterReceiver(receiver);
    }

In the service, when you’re done, just call…

sendBroadcast(new Intent(YourActivityClass.ACTION_STRING));

If you want to include some data, just put it in the intent like you would when starting an Activity.

If your Activity is off screen when the service completes, and the user goes back to it, you’ll have missed the notification. That’s a different issue to resolve.