gistfile1.txt

public class MainActivity extends Activity implements View.OnClickListener {
  
  @Override
  protected void onCreate(Bundle savedInstanceState) {
    Button clickMe = (Button) findViewById(R.id.button_name);
    clickMe.setOnClickListener(this);
  }

  @Override
  public void onClick(View view) {
    if(view.getId() == R.id.button_name) {
      // handle button click event. Since the view in this scope, is your
      // button, you could change the text on it here.
    }
  }
}