java运用JFrame实现弹出右键菜单改变界面的背景颜色，其颜色选择项有蓝色，粉红色，黄色，红，橙色
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JPopMenuDemo.java import java.awt.*; import java.awt.event.*; import javax.swing.*; //右键弹出菜单选择背景颜色 public class JPopMenuDemo extends JFrame { JRadioButtonMenuItem items[]; //菜单项 Color[] colors={Color.blue,Color.pink,Color.yellow,Color.red,Color.orange}; //颜色数组 JPopupMenu popupMenu; //弹出菜单 public JPopMenuDemo() { super( "右键弹出菜单" ); //调用父类构造函数 ChangeColorAction action = new ChangeColorAction(); //菜单项事件处理 String[] str = {"Blue","Pink","Yellow","Red","Orange"}; //菜单项名称 ButtonGroup colorGroup=new ButtonGroup(); //实例化按钮组 popupMenu=new JPopupMenu(); //实例化弹出菜单 items=new JRadioButtonMenuItem[5]; //初始化数组 for (int i=0;i<items.length;i++) { items[i]=new JRadioButtonMenuItem(str[i]); //实例化菜单项 popupMenu.add(items[i]); //增加菜单项到菜单上 colorGroup.add(items[i]); //增加菜单项到按钮组 items[i].addActionListener(action); //菜单项事件处理 } addMouseListener(new MouseAdapter(){ //窗口的鼠标事件处理 public void mousePRessed( MouseEvent event ) { //点击鼠标 triggerEvent(event); //调用triggerEvent方法处理事件 } public void mouseReleased( MouseEvent event ) { //释放鼠标 triggerEvent(event); } private void triggerEvent(MouseEvent event) { //处理事件 if (event.isPopupTrigger()) //如果是弹出菜单事件(根据平台不同可能不同) popupMenu.show(event.getComponent(),event.getX(),event.getY()); //显示菜单 } }); getContentPane().setBackground(Color.white); //窗口的默认背景色为白色 setSize(230,160); //设置窗口大小 setVisible(true); //设置窗口为可视 setDefaultCloSEOperation(JFrame.EXIT_ON_CLOSE ); //关闭窗口时退出程序 } class ChangeColorAction implements ActionListener { //菜单项事件处理 public void actionPerformed(ActionEvent event) { for (int i=0;i<items.length;i++) if (event.getSource()==items[i]) { //判断事件来自于哪个菜单项 getContentPane().setBackground(colors[i]); //设置窗口背景 repaint(); //重绘窗口 return; } } } public static void main( String args[]) { new JPopMenuDemo(); } } 新闻热点
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