Question

java JButton 点击按钮 背景变色

import java.awt.Color;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;

public class Study extends JFrame implements ActionListener{
JButton btn ;
public Study(){
btn = new JButton();
this.setTitle("111");
this.setSize(500, 500);
this.add(btn);
btn.setBounds(100, 100, 100, 100);
setLayout(new FlowLayout());
this.setVisible(true);
}
public static void main(String[] args) {
// TODO Auto-generated method stub
new Study();
}
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
btn.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stu
setBackground(Color.red);
}
});
}

}
//改那里可以实现

Answer 1

setBackground设置背景色！可使用JPanel

布局随便选，下面程序使用了边框（BorderLayout）和流水(FlowLayout)2种布局方式！

顺便帮你加了一个按钮事件！有问题再追问吧！~

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;

public class Test extends JFrame implements ActionListener {
    private JPanel panel0 = null, panel2 = null;
    private JButton b1 = null, b2 = null, b3 = null, b4 = null;
    public Test() {
        Container c = this.getContentPane();
        //边框布局
        c.setLayout(new BorderLayout());
        //创建panel
        panel0 = new JPanel();
        panel2 = new JPanel();
        //为2个panel设置底色
        panel0.setBackground(Color.red);
        panel2.setBackground(Color.BLUE);
        //2个panel都是用流水布局
        panel0.setLayout(new FlowLayout());
        panel2.setLayout(new FlowLayout());
        //创建按钮
        b1 = new JButton("panel2黄色");
        b2 = new JButton("panel2绿色");
        b3 = new JButton("panel0橙色");
        b4 = new JButton("panel0灰色");
        /**
         * 添加按钮事件
         */
        b1.addActionListener(this);
        b2.addActionListener(this);
        b3.addActionListener(this);
        b4.addActionListener(this);
        /**
         * 将按钮添加相应panel上
         */
        panel0.add(b1);
        panel0.add(new JLabel());
        panel0.add(b2);
        panel2.add(b3);
        panel2.add(b4);
        /**
         * 将panel添加到容器
         */
        c.add(panel0, BorderLayout.CENTER);
        c.add(panel2, BorderLayout.EAST);
        this.setSize(500, 500);
        this.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        this.setVisible(true);
        
    }    
    public static void main(String[] args) {
        new Test();    
    }
    @Override
    public void actionPerformed(ActionEvent e) {
        // TODO Auto-generated method stub
        if (e.getSource() == b1) {
            panel2.setBackground(Color.yellow);
        } else if (e.getSource() == b2) {
            panel2.setBackground(Color.green);
        } else if (e.getSource() == b3) {
            panel0.setBackground(Color.ORANGE);
        }  else if (e.getSource() == b4) {
            panel0.setBackground(Color.GRAY);
        } 
    }
}

追问

大神。你知道我的那个哪里有错吗？

追答

加上JPanel容器，用这个改变底色，不要直接使用JFrame

Answer 2

import java.awt.Color;
import java.awt.Container;
import java.awt.FlowLayout;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

import javax.swing.JButton;
import javax.swing.JFrame;

public class Study extends JFrame{
	JButton btn ;
	public Study(){
		this.setTitle("111");
		this.setSize(500, 500);
		setLayout(new FlowLayout());
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		this.setVisible(true);
		
		final Container jp = this.getContentPane();
		btn = new JButton("abc");
		jp.add(btn);
		btn.setBounds(100, 100, 100, 100);
		btn.addActionListener(new ActionListener() {
			@Override
			public void actionPerformed(ActionEvent e) {
				if (e.getSource().equals(btn)) {
					jp.setBackground(Color.gray);
				}
			}
		});
	}
	public static void main(String[] args) {
		new Study();
	}
}

Answer 3

你在按钮里光调用了修改颜色的代码 没有调用刷新当然没用了

追问

明细一点嘛，新手

Answer 4

百度知道，，，，