Question

JAVA编一个图形化界面

JAVA编一个图形化界面，在界面上有“红”“黄”“蓝”“退出”四个按钮，点击不同颜色的按钮，界面背景变换不同颜色。谢了

Answer 1

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class Test
{
JFrame jf = new JFrame("Test"); //框体jf
JButton jb1 = new JButton("红");
JButton jb2 = new JButton("黄");
JButton jb3 = new JButton("蓝");
JButton jb4 = new JButton("退出"); //四个按钮

public Test()
{
//就不给jf布局了，直接添加按钮
jf.add(jb1,BorderLayout.NORTH);
jf.add(jb2,BorderLayout.WEST);
jf.add(jb3,BorderLayout.EAST);
jf.add(jb4,BorderLayout.SOUTH);

//给每个按钮添加监听，这里采用了匿名类，能看懂吧？
jb1.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
//swing中得先getContentPane才能设置背景色，awt中直接设置即可
jf.getContentPane().setBackground(Color.red);
}
});
jb2.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
jf.getContentPane().setBackground(Color.yellow);
}
});
jb3.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
jf.getContentPane().setBackground(Color.blue);
}
});
jb4.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent e)
{
System.exit(0);
}
});

jf.setSize(400, 400); //设置大小
jf.setLocation(300, 100); //设置位置
jf.setResizable(false); //设置不可调整大小
jf.setVisible(true); //设置可见
jf.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE); //设置退出时关闭
}

public static void main(String[] args)
{
Test t = new Test();
}
}

刚学完JavaSE着部分，可以复制到eclipse之类的直接运行，

希望对你有帮助。

Answer 2

import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
/**
* @author Hardneedl
*/
final class ButtonColorDemo extends JFrame {
public String getTitle() {return "ButtonColor";}
static private final Dimension size = new Dimension(600, 400);
public Dimension getPreferredSize() {return size;}
public Dimension getMaximumSize() {return size;}
public Dimension getMinimumSize() {return size;}
public Dimension getSize() {return size;}
private Container container;
ButtonColorDemo() throws HeadlessException {
attachListeners();
doLay();
}
private void attachListeners() {setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);}
private void doLay() {
container = getContentPane();
container.setLayout(new FlowLayout(FlowLayout.LEADING, 5,5));
container.add(new JButton(new ColorAction("Red",Color.RED)) );
container.add(new JButton(new ColorAction("Yellow",Color.YELLOW)) );
container.add(new JButton(new ColorAction("Blue",Color.BLUE)) );
container.add(new JButton(new ExitAction("Exit")) );
pack();
setVisible(true);
}
private class ColorAction extends AbstractAction {
private Color color;
private ColorAction(String name,Color c) {
super(name);
color=c;
}
public void actionPerformed(ActionEvent e) {container.setBackground(color);}
}
private static class ExitAction extends AbstractAction {
private ExitAction(String s) {super(s);}
public void actionPerformed(ActionEvent e) {System.exit(0);}
}
public static void main(String[] args) {
SwingUtilities.invokeLater(new Runnable() {public void run() {new ButtonColorDemo();}});
}
}