import javax.swing.*;
import java.awt.*;
public class ControlCircleWithoutEventHandling extends JFrame {
private JButton jbtEnlarge = new JButton("Enlarge");
private JButton jbtShrink = new JButton("Shrink");
private CirclePanel canvas = new CirclePanel();
public ControlCircleWithoutEventHandling() {
JPanel panel = new JPanel();
panel.add(jbtEnlarge);
panel.add(jbtShrink);
this.add(canvas, BorderLayout.CENTER);
this.add(panel, BorderLayout.SOUTH);
}
public static void main(String[] args) {
JFrame frame = new ControlCircleWithoutEventHandling();
frame.setTitle("ControlCircleWithoutEventHandling");
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(200, 200);
frame.setVisible(true);
}
}
class CirclePanel extends JPanel {
private int radius = 5;
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawOval(getWidth() / 2 - radius, getHeight() / 2 - radius,
2 * radius, 2 * radius);
}
}