import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
public class ControlCircleWithMouseAndKey extends JFrame {
private JButton jbtEnlarge = new JButton("Enlarge");
private JButton jbtShrink = new JButton("Shrink");
private CirclePanel canvas = new CirclePanel();
public ControlCircleWithMouseAndKey() {
JPanel panel = new JPanel();
panel.add(jbtEnlarge);
panel.add(jbtShrink);
this.add(canvas, BorderLayout.CENTER);
this.add(panel, BorderLayout.SOUTH);
jbtEnlarge.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
canvas.enlarge();
canvas.requestFocusInWindow();
}
});
jbtShrink.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
canvas.shrink();
canvas.requestFocusInWindow();
}
});
canvas.addMouseListener(new MouseAdapter() {
@Override
public void mouseClicked(MouseEvent e) {
if (e.getButton() == MouseEvent.BUTTON1)
canvas.enlarge();
else if (e.getButton() == MouseEvent.BUTTON3)
canvas.shrink();
}
});
canvas.setFocusable(true);
canvas.addKeyListener(new KeyAdapter() {
@Override
public void keyPressed(KeyEvent e) {
if (e.getKeyCode() == KeyEvent.VK_UP)
canvas.enlarge();
else if (e.getKeyCode() == KeyEvent.VK_DOWN)
canvas.shrink();
}
});
}
public static void main(String[] args) {
JFrame frame = new ControlCircleWithMouseAndKey();
frame.setTitle("ControlCircle");
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setSize(200, 200);
frame.setVisible(true);
}
class CirclePanel extends JPanel {
private int radius = 5;
public void enlarge() {
radius++;
repaint();
}
public void shrink() {
if (radius >= 1) radius--;
repaint();
}
@Override
protected void paintComponent(Graphics g) {
super.paintComponent(g);
g.drawOval(getWidth() / 2 - radius, getHeight() / 2 - radius,
2 * radius, 2 * radius);
}
}
}