Run Handler messages in a background thread

You can simply do this:

private Handler mHandler;

private HandlerThread mHandlerThread;

public void startHandlerThread(){
    mHandlerThread = new HandlerThread("HandlerThread");
    mHandlerThread.start();
    mHandler = new Handler(mHandlerThread.getLooper());
}

Then invoke with:

mHandler.postDelayed(new Runnable() {
        @Override
        public void run() {
          // Your task goes here
        }
    },1000);