📄 buttontest.java
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/**
* @version 1.10 25 Mar 1997
* @author Cay Horstmann
*/
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
class ButtonPanel extends JPanel
implements ActionListener
{ public ButtonPanel()
{ yellowButton = new JButton("Yellow");
blueButton = new JButton("Blue");
redButton = new JButton("Red");
add(yellowButton);
add(blueButton);
add(redButton);
yellowButton.addActionListener(this);
blueButton.addActionListener(this);
redButton.addActionListener(this);
}
public void actionPerformed(ActionEvent evt)
{ Object source = evt.getSource();
Color color = getBackground();
if (source == yellowButton) color = Color.yellow;
else if (source == blueButton) color = Color.blue;
else if (source == redButton) color = Color.red;
setBackground(color);
repaint();
}
private JButton yellowButton;
private JButton blueButton;
private JButton redButton;
}
class ButtonFrame extends JFrame
{ public ButtonFrame()
{ setTitle("ButtonTest");
setSize(300, 200);
addWindowListener(new WindowAdapter()
{ public void windowClosing(WindowEvent e)
{ System.exit(0);
}
} );
Container contentPane = getContentPane();
contentPane.add(new ButtonPanel());
}
}
public class ButtonTest
{ public static void main(String[] args)
{ JFrame frame = new ButtonFrame();
frame.show();
}
}
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