Trigger action after picture is clicked

There is a button picture in my 2D game. I placed the picture in certain region of screen. When the touch occurs within the region of button, some action executes. But I want to implement it like the picture itself listen to the touch input. How to implement that?

My current code is shown below:

sbMidSq1X ,sbMidSq2X, sbMidSq3Y and sbMidSq2Y are boundaries of picture region.

public void onTouchEvent(TouchEvent evt) {

    if ((Boolean) player.getUserData("alive")) {
        if (evt.getType().TAP.equals(TouchEvent.Type.TAP)) {
            //shoot Bullet
            if(evt.getX() >= sbMidSq1X && evt.getX() <= sbMidSq2X
              && evt.getY() >= sbMidSq3Y && evt.getY() <= sbMidSq2Y)
            {    
                
                if (System.currentTimeMillis() - bulletCooldown > 83f) {
                    bulletCooldown = System.currentTimeMillis();

                    Vector3f aim = getAimDirection();
                    Vector3f offset = new Vector3f(aim.y/3,-aim.x/3,0);
                    

//                    init bullet 1
                    Spatial bullet = getSpatial("Bullet");
                    Vector3f finalOffset = aim.add(offset).mult(30);
                    Vector3f trans = player.getLocalTranslation().add(finalOffset);
                    bullet.setLocalTranslation(trans);
                    bullet.addControl(new BulletControl(aim, settings.getWidth(), settings.getHeight(), particleManager/*,grid*/));
                    bulletNode.attachChild(bullet);

//                    init bullet 2
                    Spatial bullet2 = getSpatial("Bullet");
                    finalOffset = aim.add(offset.negate()).mult(30);
                    trans = player.getLocalTranslation().add(finalOffset);
                    bullet2.setLocalTranslation(trans);
                    bullet2.addControl(new BulletControl(aim, settings.getWidth(), settings.getHeight(), particleManager/*,grid*/));
                    bulletNode.attachChild(bullet2);

                    sound.shoot();
                }
            }
        }
    }        


}

If you want to add listeners directly to a spatial then you will need some picking infrastructure that does that for you. Lemur has such a thing that works with any JME Spatial.

This works with 2D or 3D objects just the same.

Lemur repo is here:

Lemur docs are here: