活动处于暂停状态或处于停止状态时，服务发送到活动

Question

Anyone know can activity received the message send by service while activity is in onStop or onPause State? How should I handle so that Activity will received the message send by service while in background? I have an Activity which is received locations send by service from the background. My activity is updating how much user travel every 10 seconds. If the activity is in onPause mode, I don't think activity can do any calculation send by service.

Answer 1

Yes and no. Your activity can't actually receive broadcasts while it's paused or stopped, but you can have your broadcast cause it to be woken back up. But that's probably not something you want to do every 10 seconds. It would likely be better to just keep the knowledge in the service and have the activity ask for it when it gets restarted. If that's an approach you're after I can point you to some examples.

Answer 2

I would recommend you to do the following :

1. Whatever computation you do, do it in the service. So you will always have the state of user maintained somewhere.

2. When your activity starts, 'Bind' the service to the activity and call your function of the service FROM the activity to retrieve the state of the user. You can use the 'ServiceConnection' class for this in the activity.

3. You can call your function of the service from the activity in your 'onResume' function of the activity.

Viewable content should be in the activity and all the other data in the service. When you do the above, the user will see the latest stuff that you want to show. There is no point in sending data to the activity and doing the computation there even if the user does not see it.