题目内容:
本题是一个Applet,页面上有一个按钮“请单击”,单击该按钮后弹出一个对话框,对话框上有三个按钮“橙色”、“蓝色”和“红色”,单击其中任意一个按钮,则可以将对话框的背景色设置为按钮名称所对应的颜色。 import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class java2 extends JApplet
{
private JFrame framet;
()
{
frame=new JFrame();
frame.setTitle("java2");
frame.setSize(300,200);
frame.getContentPane().add(new ButtonPanel
());
JButton PopButton=new JButton("请单击");
getContentPane().add(PopButton);
PopButtom addActionListener(new ActionListener();
{
public void actionPerformed(ActionEvent evt)
{
if(frame.isVisible())frame.setVisible(false);
else ;
}
});
}
}
class ButtonPanel extends JPanel
{
private class ColorAction implements ActionLis-
tener
{
private Color backgroundColor;
public void actionPerformed(ActionEvent action-
event)
{
setBackground(backgroundColor);
repaint();
}
public ColorAction(Color color)
{
backgroundColor=color;
}
}
public ButtonPanel()
{
JButton jbutton=new JButton("橙色");
JButton jbuttonl=new JButton("蓝色");
JButton jbutton2=new JButton("红色");
add(jbutton);
add(jbuttonl);
add(jbutton2);
ColorAction coloraction=new ColorAction(Color.orange);
ColorAction coloractionl=new ColorAction(Color.blue);
ColorAction coloraetion2=new ColorAction(Color.red);
ibutton.addActionListener(coloraction);
ibuttonl.addActionListener(coloractionl);
jbutton2.addActionListener(coloraction2);
}
}
参考答案:
答案解析: