How to change the Imagerecource when Button is clicked

I want to click on an ImageView and when a certain amount of clickes is reached, I want the Imageview to change the image. This is my code but I dont know where the problem is. There is no error or something. The Picture just doesnt change Can you guys help me please. Thanks

        @Override
        public void onClick(View v) {
            counter++;



        }

    });

    if (counter == 10){
        ImageView megg = (ImageView) findViewById(R.id.egg);
        megg.setImageResource(R.drawable.egg100);

    }

    if (counter == 100){
        ImageView megg = (ImageView) findViewById(R.id.egg);
        megg.setImageResource(R.drawable.egg100);

    }
    if (counter == 500){
        ImageView megg = (ImageView) findViewById(R.id.egg);
        megg.setImageResource(R.drawable.egg500);

    }