首先，每当需要更改表示内容的颜色时，请始终将
Opaque属性设置为true。就像您的情况一样，
JPanel首先必须使用
panelObject.setOpaque(true)，对于某些
LookAnd Feel调用此方法是必须执行背景颜色更改的。
关于其余部分，请尝试下面的代码示例：
import java.awt.*;import java.awt.event.*;import javax.swing.*;public class ColourTimer{ private JPanel contentPane; private Timer timer; private int counter; private Color[] colours = { Color.RED, Color.WHITE, Color.BLUE, Color.DARK_GRAY, Color.YELLOW, Color.LIGHT_GRAY, Color.BLACK, Color.MAGENTA, Color.PINK, Color.CYAN }; private ActionListener timerAction = new ActionListener() { @Override public void actionPerformed(ActionEvent ae) { if (counter == (colours.length - 1)) counter = 0; contentPane.setBackground(colours[counter++]); } }; public ColourTimer() { counter = 0; } private void displayGUI() { Jframe frame = new Jframe("Colour Timer"); frame.setDefaultCloseOperation(Jframe.DISPOSE_ON_CLOSE); contentPane = new JPanel(); contentPane.setOpaque(true); final JButton button = new JButton("STOP"); button.addActionListener(new ActionListener() { @Override public void actionPerformed(ActionEvent ae) { if (timer.isRunning()) { button.setText("START"); timer.stop(); } else { button.setText("STOP"); timer.start(); } } }); frame.getContentPane().add(contentPane, BorderLayout.CENTER); frame.getContentPane().add(button, BorderLayout.PAGE_END); frame.setSize(300, 200); frame.setLocationByPlatform(true); frame.setVisible(true); timer = new Timer(2000, timerAction); timer.start(); } public static void main(String... args) { EventQueue.invokeLater(new Runnable() { @Override public void run() { new ColourTimer().displayGUI(); } }); }}
