How to make an activity stop, rather then be destroyed, from the BACK key?

Question

Right now an activity gets destroyed when the BACK key is pressed. How can I make it just stop ( i.e. keep all the variables, etc. alive ), rather then be destroyed?

Answer 1

Pressing the BACK key triggers the onBackPressed callback method of Activity class. The default implementation of this callback calls the finish() method.

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

You can override this method to move the activity to background (mimick the action of pressing the HOME key.

eg:

@Override
public void onBackPressed() {
    onKeyDown(KeyEvent.KEYCODE_HOME);        
}

You could also instead consider moveTaskToBackground() mentioned here:

Override back button to act like home button