Button.java

class Button {
  Color background;
  Content content;
  float x, y, width, height;
  OnClickListener clickListener;
  
  void measure() {
    // compute preferred size
  }
  
  void layout(float x, float y, float width, float height) {
    // save position and size, and layout content here
  }
  
  void draw() {
    // draw background and content
  }
  
  void dispatchMouseEvent(MouseEvent event) {
    // if clicked, fire clickListener
  }
}