android自定义侦听器-如何注销

Question

I have written a custom listener in my android app as below:

private OnListener l = new OnListener() {
@Override
public void OnReceive() {
  Log.v(TAG, "Received response");
};

It works well, however, when I set l = null, it still invokes OnReceive(). It's probably because it runs in a separate thread and the reference to it still exists in the event caller function. However, how I can make sure if I set it to null, it doesn't receive anything? Or how can I unregister a listener?

Answer 1

I don't know about events and threads, but if you set a null listener to your control, it should unregister.

I tried this:

int timesFired=0;
Button btn2, btn1;
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    final TextView txt=(TextView)findViewById(R.id.textView1);
    btn1=(Button)findViewById(R.id.btn1);

    btn2=(Button)findViewById(R.id.btn2);
    btn1.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View arg0) {
            // TODO Auto-generated method stub
            timesFired++;
            txt.setText("btn1's listener fired " + timesFired);
        }
    });

    btn2.setOnClickListener(new OnClickListener() {
        @Override
        public void onClick(View v) {
            btn1.setOnClickListener(null);
            txt.setText("btn1 unregistered");
        }
    });
}

And it does what it's supposed to.