How to catch event of coming back to an activity after hitting back

问题

I have a main screen for my application which then leads to different screens, from each of those hitting back takes you back to the main screen. I want to do some stuff every time a user is "coming back" to the main screen, How do I catch this kind of event???

回答1:

Use onResume() method in your main activity or Use startActivityForResult method in your activity by overriding the keyDown method in sub activities,it may help you

回答2:

you cand try this:

    @Override
    public boolean onKeyDown(int keyCode, KeyEvent event) {
       if ((keyCode == KeyEvent.KEYCODE_BACK)) {
       //your stuff goes here
       }
    return super.onKeyDown(keyCode, event);
    }

回答3:

You could do something like -

@Override
public boolean onKeyDown(int keyCode, KeyEvent event) {
    if (keyCode == KeyEvent.KEYCODE_BACK) {
       // Do your stuff
       return true;
   }
   return super.onKeyDown(keyCode, event);
}

来源：https://stackoverflow.com/questions/6636039/how-to-catch-event-of-coming-back-to-an-activity-after-hitting-back