Question

I’m trying to change a boolean value only on home button press. Can anyone tell me a solution for this?

Answer 1

Look at onUserLeaveHint() :

Called as part of the activity lifecycle when an activity is about to
go into the background as the result of user choice. For example, when
the user presses the Home key, onUserLeaveHint() will be called, but
when an incoming phone call causes the in-call Activity to be
automatically brought to the foreground, onUserLeaveHint() will not be
called on the activity being interrupted. In cases when it is invoked,
this method is called right before the activity’s onPause() callback.

make Boolean variable true inside onUserLeaveHint() as:

 @Override
    public void onUserLeaveHint() {
                super.onUserLeaveHint();
                //make Boolean true here because this method first  
                //called when user press home key
            }