import java.awt.*; import javax.swing.*; public class Fond { private JButton Cyan, Magenta, Jaune; public Fond() { this.setLayout(null); this.Cyan = new JButton("Cyan"); this.Magenta = new JButton("Magenta"); this.Jaune = new JButton("Jaune"); this.Cyan.setBounds(100,50,100,20); this.Magenta.setBounds(220,50,100,20); this.Jaune.setBounds(320,50,100,20); this.Cyan.addActionListener(this); this.Magenta.addActionListener(this); this.Jaune.addActionListener(this); frame.add(this.Cyan); frame.add(this.Magenta); frame.add(this.Jaune); } @Override public void actionPerformed(ActionEvent evenement) { if (evenement.getSource() == this.Cyan) { frame.setBackground(Color.CYAN); } else if (evenement.getSource() == this.Magenta) { frame.setBackground(Color.MAGENTA); } else if (evenement.getSource() == this.Jaune) { frame.setBackground(Color.JAUNE); } } }