Notify Activity in Android to refresh when data is updated

Question

I have a background Service which updates the database in an Android App. In the App this data is displayed, but I am having trouble finding a good way to trigger a refresh of the data.

Initially I just refreshed each time a view resumed, but that doesn't work obviously if the data is updated while the view is shown.

On iOS I use notifications, which I register in the view, and is triggered by the update process when completed. Is there a way to do something similar in Android to trigger an update on the UI thread from a background thread?

you can use Broadcast receiver component of android to get to know your desired trigger — Durgesh Patel, Aug 27 '15 at 09:05
You can use a BroadCastReceiver with the custom intnet. Whenever that custom intent is fired you can refresh the data. — RajSharma, Aug 27 '15 at 09:14

score 3 · Accepted Answer · answered Aug 27 '15 at 09:16

BroadcastReciever in your Activity is the best way to update Activity from the Service.

Activity:

 BroadcastReceiver br = new BroadcastReceiver() {
    @Override
    public void onReceive(Context context, Intent intent) {

    }
}

After that, all you need is to register some action for it in Activity:

 public final static String BROADCAST_ACTION = "com.example.action";

 IntentFilter intFilt = new IntentFilter(BROADCAST_ACTION);
registerReceiver(br, intFilt);

In your service you should build an intent and call sendBroadcast.

Service:

Intent intent = new Intent(MainActivity.BROADCAST_ACTION);
sendBroadcast(intent);

score 2 · Answer 2 · edited May 23 '17 at 12:22

2

There's no need to use a BroadCastReceiver if you update your database and you're using a ContentProvider to saving your data to the db then whenever data change on the ContentProvider it should notify that data has changed and in your on your activity you use a CursorLoader then the Loader is notified and UI updated, this is very easy to do and has the advantage that a CursorLoader will run the thread on background see more here and here

edited May 23 '17 at 12:22

Community

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answered Aug 27 '15 at 09:27

forcewill

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Thanks for this tip, I will need to look into that. That is a much more elegant solution then just to reload. – Luuk D. Jansen Aug 27 '15 at 18:14

Notify Activity in Android to refresh when data is updated

2 Answers2