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I want to know how to exit an app when user press the Home Button.

As far as i know that Home Button moves the running app in background and puts Launcher process in front.

I know i can use finish() but i don't know where i should call it because i have no idea which function is going to get a call when user will press the Home Key.

Thanks.

Gerald Schneider
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Varundroid
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    Whatever problem you think you are solving this way can be better solved with other techniques. I have not encountered a valid reason to proactively destroy an activity because the user, say, responds to a `Notification`. For example, if you are doing this for security (e.g., force a login), please do it based on time. Whether the user presses HOME or responds to a `Notification` or whatever should have no bearing, any more than if the user switches browser tabs away from a Web app should cause them to be automatically logged out of the Web app. – CommonsWare Apr 30 '11 at 18:38
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    Similarly, if you are destroying the activity proactively because you are crashing when the user returns to the activity, please just fix the bug, rather than cause the user to lose context. And, to top it off, this is only really useful if you have a single-activity application, as there is nothing in Android to allow you to "exit an app", period. If you feel that this is still somehow justified in your scenario, I'd love for you to try to convince me. – CommonsWare Apr 30 '11 at 18:40
  • @CommonsWare i think you are right. i should try to find an other option to handle home key instead of destroying my app. Thanks for waking me up. But my problem is very simple, my app is not crashing when user pressing the home key. Actually the problem is in my home screen widget because whenever i exit my app by pressing the home key and after that if i click on my home screen widget then it is starting the main activity again after performing the necessary tasks. – Varundroid Apr 30 '11 at 20:59
  • I am interpreting this as "you click on something in the app widget, it opens up Activity B, then BACK returns the user to Activity A that had already been running". If that's the case, try adding `FLAG_ACTIVITY_NEW_TASK` to your `Intent` in the `PendingIntent` in the app widget. If that doesn't work, try `FLAG_ACTIVITY_CLEAR_TOP`. And if I misunderstood the symptoms, my apologies. – CommonsWare Apr 30 '11 at 22:03
  • @CommonsWare - I totally agree that from a design / user experience point of view it is very bad/pointless to try and kill the application when the user presses the home button. However, sometimes clients want this behaviour and will not budge. – Dean Wild Jan 16 '12 at 15:15

2 Answers2

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Depending on what you want to do, overriding onUserLeaveHint might be the best bet:

http://developer.android.com/reference/android/app/Activity.html#onUserLeaveHint()

This will let your app know that your app is being exited because the user chose to switch apps (Like by hitting the Home button or selecting a notification). This hint function will not be called if an incoming phone call (or similar) is causing your app to go to the background, as the user didn't initiate that action.

Kevin TeslaCoil
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    Thanks. This is exactly what i was looking for. I don't know why CommonsWare said "This is not supported in android" when Android provide us this method to perform tasks which we want to perform at Home Key event. STRANGE!! – Varundroid Apr 30 '11 at 17:53
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    @Varundroid: I keep forgetting about that method. It doesn't really matter, as you can't "exit an app", regardless. I also worry a bit over when `onUserLeaveHint()` returns `true` or `false` -- the docs outline two scenarios, but there are many more than that. – CommonsWare Apr 30 '11 at 18:42
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    onUserLeaveHint() also fires if you start a new intent annoyingly – Dean Wild Jan 16 '12 at 15:11
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In my case,

I have many activities in application so if I use 'onUserLeaveHint', 'onStop' or ...

It just catch activity transition.

So I put below code every activities. And finally catch user's home button action.

first, you have singleton object

public class ActivityContext {
    public static Context context = null;
}

and every activities,

@Override
protected void onStop(){  //onStop runs after New one's onResume
    super.onStop();
    if(ActivityContext.context==context) { //user home button out
        AppStartEnd.sendAppEndData(context);
    }
}
@Override
protected void onResume(){  
    super.onResume();
    ActivityContext.context = YourActivity.this;
}

I hope this will help you

Wonjun Hwang
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