import java.awt.event.*; import javax.swing.*; class ButtonPanel extends JPanel { private JButton inc; private JButton dec; private JLabel resultLabel; private int num = 1; public ButtonPanel(){ resultLabel = new JLabel("Value: 1"); inc = new JButton("Increment"); dec = new JButton("Decrement"); inc.addActionListener(new ButtonsListener1()); dec.addActionListener(new ButtonsListener2()); add(inc); add(dec); add(resultLabel); } private class ButtonsListener1 implements ActionListener { public void actionPerformed (ActionEvent evt) { num++; resultLabel.setText("Value: " + num); } } private class ButtonsListener2 implements ActionListener { public void actionPerformed (ActionEvent evt) { num--; resultLabel.setText("Value: " + num); } } }
-and-
import javax.swing.*; public class Activity4B { public static void main( String[] args ) { JFrame frame = new JFrame(); frame.setTitle( "Increment/Decrement Valule" ); frame.setBounds( 300, 300, 300, 200 ); frame.setDefaultCloseOperation (JFrame.EXIT_ON_CLOSE); frame.getContentPane().add( new ButtonPane1() ); frame.setVisible (true); } }