Can't create handler inside thread Thread[Thread-4,5,main] that has not called Looper.prepare() code example

Example: Can't create handler inside thread Thread[DefaultDispatcher-worker-1,5,main] that has not called Looper.prepare()

mHandler = new Handler(Looper.getMainLooper()) {
    @Override
    public void handleMessage(Message message) {
        // This is where you do your work in the UI thread.
        // Your worker tells you in the message what to do.
    }
};

void workerThread() {
    // And this is how you call it from the worker thread:
    Message message = mHandler.obtainMessage(command, parameter);
    message.sendToTarget();
}