Question

I wish to do something(call a function), if for a particular time interval the screen wasn’t touched or was remained inactive.
How can I achieve this in Android?

Any suggestions.

Answer 1

You can send a delayed message to the handler of UI thread in onResume() method:

handler.sendEmptyMessageDelayed(SCREEN_INACTIVE_MSG, DELAY_MILIS);

Then, in onTouchEvent remove the message and insert it again:

handler.removeMessages(SCREEN_INACTIVE_MSG);
handler.sendEmptyMessageDelayed(SCREEN_INACTIVE_MSG, DELAY_MILIS);

In your handler, override handleMessage() method, to handle the message:

public void handleMessage (Message msg) {
    switch(msg.what) {
        case SCREEN_INACTIVE_MSG:
            handleIdleScreenMetohd();
            break;
    }
}

Also, remove the message from the handler in onPause().

This assumes that your activity is active for the whole time (not paused etc.). Handling screen inactivity outside of your app seems impossible.