How do you bring back a destroyed activity?

Question

I have an application that starts activity A. The user can then start service S from activity A. When a certain event happens, service S starts activity B. Activity B only has one button, and when pushed, should return to activity A. Everything works fine, except for when activity A was closed out using the back key. When the back key is pressed, instead of onPause, onDestroy is called. So when activity B is dismissed, I get sent back to the homepage instead of Activity A. So my question is, how can I make sure that Activity B reopens activity A if activity A is onPause, and also reopens the activity A when it's onDestroy has been called. I'm thinking to use intent filters, but I can't figure out to get the right combination. I do not want multiple instances of Activity A. Thanks for the help.

Answer 1

on activity A:

public void onBackPressed() {
    moveTaskToBack(true);
}

or on Activity B, force it to start activity A,

public void onBackPressed() {
    Intent i = new Intent(B.this, A.class);
    startactivity(i);
}

but since you implement the first one, you dont need this last code.

I Hope it helps