BroadcastReceiver or Messenger via Handler
android, android-sdk-2.1, android-service
Solution
If your `IntentService` does not know whether the activity will exist (e.g., might have been destroyed), or if there are multiple activities that might be in the foreground and would want to know about what's going on, I'd use `sendOrderedBroadcast()`. You can arrange to then also have a "backstop" `BroadcastReceiver` that could raise a Notification, if desired, as I outline in this blog post and demonstrate in this sample project.
Either of your techniques can work, though.
Problem
I have an `IntentService` which need to pass a message to an `Activity`. I know two ways of doing so. use `sendBroadcast()` at the `Service` side while registering a `broadcastReciever` at the `Activity` side which will receiver the message. passing a `Messenger` to the Service `side`, which will point to a `Handler` at the `Activity` side, which will be ready to receive that message from the service. Which one is good for which purpose? Or both of them do the same?