Android Custom Event Listener

Say I want to make my own event listener for my class, how do I do that? Do I need to maintain a thread manually?

Solution 1:

public class CustomView extends View(){
OnCustomEventListener mListener;
:
://some code
:
:

Create an interface that will be implemented by your activity:

public interface OnCustomEventListener {
    void onEvent();
}

public void setCustomEventListener(OnCustomEventListener eventListener) {
    mListener = eventListener;
}

Now you need to know when the event is actually occurring. For example when the user touches a point on screen, override onTouchEvent method:

onTouchEvent(MotionEvent ev) {
    if (ev.getAction==MotionEvent.ACTION_DOWN) {
        if(mListener!=null) 
            mListener.onEvent();
    }
}

Similarly, you can create a specific event that you want. (examples could be touch down, wait for exactly 2 seconds and release- you would need to do some logic inside touch event).

In your activity, you can use the customView object to set an eventListener as such:

 customView.setCustomEventListener(new OnCustomEventListener() {
    public void onEvent() {
        //do whatever you want to do when the event is performed.
    }
 });   

Solution 2:

It can be done in the following way

First create an interface class :

public interface OnStopTrackEventListener {
    public void onStopTrack();
}

Then create the class that controls the interface :

public class Player {

    private OnStopTrackEventListener mOnStopTrackEventListener;

    public void setOnStopTrackEventListener(OnStopTrackEventListener eventListener)
    {
        mOnStopTrackEventListener = eventListener;
    }

    public void stop()
    {
        if(mOnStopTrackEventListener != null)
        {
            mOnStopTrackEventListener.onStopTrack();
        }

    }
}

That is all. Let's use it now

Player player = new Player();
player.stop(); //We are stopping music
player.setOnStopTrackEventListener(new OnStopTrackEventListener() {
      @Override
      public void onStopTrack() {
           //Code to work when music stops
      }
});