package CustomJPanel; import java.awt.FlowLayout; import javax.swing.JButton; import javax.swing.JPanel; public class MyJPanel extends JPanel { private int counter; public MyJPanel() { super(); counter = 0; this.setLayout(new FlowLayout(FlowLayout.CENTER)); this.setSize(300, 200); JButton button = new JButton(); button.setText("Click Me!"); button.addActionListener((v) -> { counter += 1; button.setText("You've clicked the button " + counter + " times!"); }); this.add(button); } }