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import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.ItemEvent;
import java.awt.event.ItemListener;
import javax.swing.JButton;
import javax.swing.JCheckBox;
import javax.swing.JFrame;
import javax.swing.JPanel;
public class RemoveListener {
class ButtonListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
System.out.println(++count);
}
}
JButton add = new JButton("+");
JCheckBox active = new JCheckBox("Active listener");
ButtonListener buttonlistener = new ButtonListener();
int count = 0;
public RemoveListener() {
JPanel panel = new JPanel();
active.addItemListener(new ItemListener() {
public void itemStateChanged(ItemEvent event) {
if (active.isSelected()) {
add.addActionListener(buttonlistener);
} else {
add.removeActionListener(buttonlistener);
}
}
});
panel.add(add);
panel.add(active);
JFrame f = new JFrame();
f.add(panel);
f.setSize(310, 200);
f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
f.setVisible(true);
}
public static void main(String[] args) {
new RemoveListener();
}
}
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