Show a notification only if Activity is not showing

Question

I have a background task I would like to handle. The thing is that when the task completes, I would like to call a new Activity to show the result to the user, only if my main Activity is showing, otherwise I would like to send just a notification so the user can see that the action completed, and be able to open it whenever he likes.

I was thinking of using a service to handle the start and termination of the background task and broadcast a message when it finishes, but in this case I have no option to know whether the Activity was shown or the broadcast was not processed and I should send a notification.

So this is my problem, and because my knowledge and experience in background tasks and services is limited I decided to ask for some help.

Thanks in advance for reading my case, hope for some help!

Answer 1

Here's a good article which describes how to implement what you want: Activity or Notification via Ordered Broadcast.

The main idea is to use ordered broadcasts. You should create a BroadcastReceiver which will live without any activities. In order to do that you should declare it in the AndroidManifest.xml file. This receiver will show a Notification. Also you should register another BroadcastReceiver with higher priority in your main activity which will display something on the screen. Then you just need to send an ordered broadcast.