13：GUI编程 || 纵然过时也不失为一种乐趣

GUI编程

一、简介

组件：

窗口
弹窗
面板
文本框
列表框
按钮
图片
监听事件
鼠标键盘事件

GUI核心技术：Swing编程、AWT编程

不流行的原因：

界面不美观
需要JRE环境（很大）

为什么要学习：

可以写出心中想要的一些小工具
工作的时候，也可能需要维护Swing界面，概率极小
了解MVC架构，了解监听！

二. AWT

抽象的窗口工具

1. AWT 介绍

GUI（Graphical User Interface）：图形用户界面（接口）

Eclipse：Java写的

包含了很多类和接口
元素：窗口，按钮，文本框
java.awt包

2. 组件和容器

（1）Frame

package xyz.dearliu.lesson01;

import java.awt.*;

/**
 * GUI第一个界面
 */
public class TestFrame {
    public static void main(String[] args) {
        //Frame  看源码
        Frame frame = new Frame("我的第一个Java图像界面窗口");
        //需要设置可见性  长宽高默认没有
        frame.setVisible(true);
        //设置窗口大小
        frame.setSize(400,400);
        //设置背景颜色 Color
        frame.setBackground(new Color(210, 210, 210));
        //弹出的初始位置
        frame.setLocation(200,200);
        //设置大小固定
        frame.setResizable(false);//默认为true
    }
}

问题：发现窗口关闭不掉，停止Java运行解决。

尝试回顾封装：

package xyz.dearliu.lesson01;

import java.awt.*;

public class TestFrame2 {
    public static void main(String[] args) {
        //展示多个窗口 new
        MyFrame myFrame1 = new MyFrame(100, 100, 200, 200, Color.blue);
        MyFrame myFrame2 = new MyFrame(300, 100, 200, 200, Color.yellow);
        MyFrame myFrame3 = new MyFrame(100, 300, 200, 200, Color.red);
        MyFrame myFrame4 = new MyFrame(300, 300, 200, 200, Color.magenta);
    }
}

class MyFrame extends Frame{
    static int id = 0; //可能存在多个窗口，需要一个计数器
    public MyFrame(int x, int y, int w, int h, Color color){
        super("MyFrame" + (++id));
        setBackground(color);
        setVisible(true);
        setBounds(x,y,w,h);

    }
}

（2）面板Panel

package xyz.dearliu.lesson01;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.awt.event.WindowListener;

/**
 * 面板 Panel  可以看成是一个空间，但是不能单独存在
 */
public class TestPanel {
    public static void main(String[] args) {
        Frame frame = new Frame();
        //布局的概念
        Panel panel = new Panel();
        //设置布局，默认什么都没有 不设置的话默认会置顶
        frame.setLayout(null);
        //坐标
        frame.setBounds(300,300,500,500);
        frame.setBackground(new Color(233, 171, 171));
        //panel设置坐标。相对于frame
        panel.setBounds(50,50,400,400);
        //设置颜色
        panel.setBackground(new Color(164, 203, 237));
        //frame.add(panel)
        frame.add(panel);
        //设置可见性
        frame.setVisible(true);
        //监听事件，监听窗口关闭事件
        //适配器模式
        frame.addWindowListener(new WindowAdapter() {
            //窗口点击关闭需要做的事情
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
}

（3）布局管理器

流式布局

package xyz.dearliu.lesson01;

import java.awt.*;

/**
 * 流式布局
 */
public class TestFlowLayout {
    public static void main(String[] args) {
        Frame frame = new Frame();
        //按钮组件
        Button button1 = new Button("button1");
        Button button2 = new Button("button2");
        Button button3 = new Button("button3");
        //设置为流式布局
        frame.setLayout(new FlowLayout());//默认居中
//        frame.setLayout(new FlowLayout(FlowLayout.LEFT));//靠左
//        frame.setLayout(new FlowLayout(FlowLayout.RIGHT));//靠右
        
        frame.setSize(200,200);
        frame.setVisible(true);

        //添加按钮
        frame.add(button1);
        frame.add(button2);
        frame.add(button3);
    }
}

东西南北中

package xyz.dearliu.lesson01;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

/**
 * 东西南北中
 */
public class TestBorderLayout {
    public static void main(String[] args) {
        Frame frame = new Frame("BorderLayout");
        Button east = new Button("East");
        Button west = new Button("West");
        Button south = new Button("South");
        Button north = new Button("North");
        Button center = new Button("Center");

        frame.add(west,BorderLayout.WEST);
        frame.add(east,BorderLayout.EAST);
        frame.add(north,BorderLayout.NORTH);
        frame.add(south,BorderLayout.SOUTH);
        frame.add(center,BorderLayout.CENTER);

        frame.setVisible(true);
        frame.setSize(200,200);
        frame.addWindowListener(new WindowAdapter() {
            //窗口点击关闭需要做的事情
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });

    }
}

网格布局

package xyz.dearliu.lesson01;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

/**
 * 网格布局
 */
public class TestGridLayout {

    public static void main(String[] args) {
        Frame frame = new Frame("BorderLayout");

        Button btn1 = new Button("btn1");
        Button btn2 = new Button("btn2");
        Button btn3 = new Button("btn3");
        Button btn4 = new Button("btn4");
        Button btn5 = new Button("btn5");
        Button btn6 = new Button("btn6");

        frame.setLayout(new GridLayout(3,2));
        frame.add(btn1);
        frame.add(btn2);
        frame.add(btn3);
        frame.add(btn4);
        frame.add(btn5);
        frame.add(btn6);

        frame.setVisible(true);
        frame.setSize(200,200);
        frame.addWindowListener(new WindowAdapter() {
            //窗口点击关闭需要做的事情
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });

//        frame.pack();//Java函数  自动优化布局 不用设置size
    }

}

（4）小练习

package xyz.dearliu.lesson01;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

/**
 * 小练习
 */
public class Excersize {
    public static void main(String[] args) {
        Frame frame = new Frame();
        Button button1 = new Button("button");
        Button button2 = new Button("button");
        Button button3 = new Button("button");
        Button button4 = new Button("button");
        Button button5 = new Button("button");
        Button button6 = new Button("button");
        Button button7 = new Button("button");
        Button button8 = new Button("button");
        Button button9 = new Button("button");
        Button button10 = new Button("button");

        Panel panel1 = new Panel();
        Panel panel2 = new Panel();


        frame.setLayout(new GridLayout(2,3));
        frame.add(button1);
        frame.add(panel1);
        panel1.setLayout(new GridLayout(2,1));
        panel1.add(button5);
        panel1.add(button6);
        frame.add(button2);
        frame.add(button3);
        frame.add(panel2);
        panel2.setLayout(new GridLayout(2,2));
        panel2.add(button7);
        panel2.add(button8);
        panel2.add(button9);
        panel2.add(button10);
        frame.add(button4);

        frame.setVisible(true);

        frame.addWindowListener(new WindowAdapter() {
            //窗口点击关闭需要做的事情
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
        frame.pack();
    }
}

（5）小结

Frame是一个顶级窗口。
Panel无法单独显示，必须添加到某个容器中。
布局管理器
1. 流式布局
2. 东南西北中
3. 表格
大小，定位，背景颜色，可见性，监听。

（6）事件监听

事件监听：当某个事情发生的时候，做出什么反应

package xyz.dearliu.lesson02;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

public class TestActionEvent {
    public static void main(String[] args) {
        //按下按钮，触发一些事件
        Button button = new Button();
        Frame frame = new Frame();
        //因为，addActionListener（）需要一个ActionListener，所以构造一个ActionListener
        MyActionListen myActionListen = new MyActionListen();
        button.addActionListener(myActionListen);
        frame.add(button,BorderLayout.CENTER);
        frame.pack();
        frame.setVisible(true);
        windowClose(frame);
    }
    //关闭窗体的实现
    private static void windowClose(Frame frame){
        frame.addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
}

class MyActionListen implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        System.out.println("aaa");
    }
}

多个按钮，共享一个事件：

package xyz.dearliu.lesson02;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TestActionEvent2 {
    public static void main(String[] args) {
        //两个按钮，实现同一个监听
        //开始 停止
        Frame frame = new Frame("开始-停止");
        Button button1 = new Button("start");
        Button button2 = new Button("stop");

        //可以显示的定义触发会返回的命令，如果不显示定义，则走默认值
        //可以多个按钮只写一个监听类
//        button2.setActionCommand("button2-stop");

        MyMonitor myMonitor = new MyMonitor();

        button1.addActionListener(myMonitor);
        button2.addActionListener(myMonitor);

        frame.add(button1,BorderLayout.NORTH);
        frame.add(button2,BorderLayout.SOUTH);
        frame.pack();
        frame.setVisible(true);

    }
}
class MyMonitor implements ActionListener{

    @Override
    public void actionPerformed(ActionEvent e) {
        //e.getActionCommand()获得按钮的信息
        System.out.println("按钮被点击了：msg"+e.getActionCommand());
        if (e.getActionCommand().equals("start")){
            
        }
    }
}

（7）输入框 TextField 监听

package xyz.dearliu.lesson02;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

public class TestText01 {
    public static void main(String[] args) {
        //启动！
        new MyFrame();
    }
}

class MyFrame extends Frame{
    public MyFrame(){
        TextField textField = new TextField();//单行文本域
        add(textField);
        //监听这个文本框输入的文字
        MyActionListener myActionListener = new MyActionListener();
        //按下enter就会触发这个输入框中的事件
        textField.addActionListener(myActionListener);

        //设置替换编码
        textField.setEchoChar('*');//文本框显示*号
        setVisible(true);
        pack();
    }
}
class MyActionListener implements ActionListener {

    @Override
    public void actionPerformed(ActionEvent e) {
        TextField te = (TextField) e.getSource();//获得一些资源,返回的一个对象
        System.out.println(te.getText());//获得输入框中的文本
        te.setText("");//回车清空
    }
}

（8）简易计算器，组合+内部类回顾复习

oop原则：组合，大于继承

计算器：

package xyz.dearliu.lesson02;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

/**
 * 简易计算器
 */
public class TestCalc {
    public static void main(String[] args) {
        new Calculator();
    }
}
//计算器类
class Calculator extends Frame {
    public Calculator(){
        //3 个文本框
        TextField num1 = new TextField(10);//10为字符数
        TextField num2 = new TextField(10);//10为字符数
        TextField num3 = new TextField(20);//10为字符数
        //1 个按钮
        Button button = new Button("=");

        button.addActionListener(new MyCalculatorListener(num1,num2,num3));
        //1 个标签
        Label label = new Label("+");

        //布局
        setLayout(new FlowLayout());

        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);
        pack();
        setVisible(true);
    }
}

//监听器类
class MyCalculatorListener implements ActionListener{
    //获取三个变量
    private TextField num1,num2,num3;

    public MyCalculatorListener(TextField num1, TextField num2, TextField num3) {
        this.num1 = num1;
        this.num2 = num2;
        this.num3 = num3;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        //1. 获得加数和被加数
        int n1 = Integer.parseInt(num1.getText());
        int n2 = Integer.parseInt(num2.getText());
        //2. 将这个值加法运算后放到第三个框
        num3.setText(""+(n1+n2));
        //3. 清楚前两个框
        num1.setText("");
        num2.setText("");
    }
}

计算器优化，完全改造为面向对象写法：

package xyz.dearliu.lesson02;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;

/**
 * 简易计算器
 */
public class TestCalc {
    public static void main(String[] args) {
        new Calculator().loadFrame();
    }
}
//计算器类
class Calculator extends Frame {
    //属性
    TextField num1,num2,num3;
    //方法
    public void loadFrame(){
        //3 个文本框
        num1 = new TextField(10);//10为字符数
        num2 = new TextField(10);//10为字符数
        num3 = new TextField(20);//10为字符数
        //1 个按钮
        Button button = new Button("=");
        //1 个标签
        Label label = new Label("+");

        //按钮监听器
        button.addActionListener(new MyCalculatorListener(this));

        //布局
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);
        pack();
        setVisible(true);
    }
}

//监听器类
class MyCalculatorListener implements ActionListener{
    //获取计算器这个对象，在一个类中组合另外一个类
    Calculator calculator = null;

    public MyCalculatorListener(Calculator calculator) {
        this.calculator = calculator;
    }

    @Override
    public void actionPerformed(ActionEvent e) {
        //1. 获得加数和被加数
        int n1 = Integer.parseInt(calculator.num1.getText());
        int n2 = Integer.parseInt(calculator.num2.getText());
        //2. 将这个值加法运算后放到第三个框
        calculator.num3.setText(""+(n1+n2));
        //3. 清楚前两个框
        calculator.num1.setText("");
        calculator.num2.setText("");
    }
}

内部类写法：

更好的包装

package xyz.dearliu.lesson02;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

/**
 * 简易计算器
 */
public class TestCalc {
    public static void main(String[] args) {
        new Calculator().loadFrame();
    }
}
//计算器类
class Calculator extends Frame {
    //属性
    TextField num1,num2,num3;
    //方法
    public void loadFrame(){
        //3 个文本框
        num1 = new TextField(10);//10为字符数
        num2 = new TextField(10);//10为字符数
        num3 = new TextField(20);//10为字符数
        //1 个按钮
        Button button = new Button("=");
        //1 个标签
        Label label = new Label("+");

        //按钮监听器
        button.addActionListener(new MyCalculatorListener());

        //布局
        setLayout(new FlowLayout());
        add(num1);
        add(label);
        add(num2);
        add(button);
        add(num3);
        setBounds(500,500,500,100);
        setVisible(true);

        //关闭
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });

    }

    //监听器类
    //内部类可以畅通无阻的访问外部类
    private class MyCalculatorListener implements ActionListener{

        @Override
        public void actionPerformed(ActionEvent e) {
            //1. 获得加数和被加数
            int n1 = Integer.parseInt(num1.getText());
            int n2 = Integer.parseInt(num2.getText());
            //2. 将这个值加法运算后放到第三个框
            num3.setText(""+(n1+n2));
            //3. 清楚前两个框
            num1.setText("");
            num2.setText("");
        }
    }
}

（9）画笔

package xyz.dearliu.lesson03;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

/**
 * 画笔
 *
 */
public class TestPaint {
    public static void main(String[] args) {
        new MyPaint().loadFrame();
    }
}

class MyPaint extends Frame{
    public void loadFrame(){
        setBounds(200,200,600,400);
        setVisible(true);
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });
    }
    //画笔
    @Override
    public void paint(Graphics g) {
        //画笔，需要有颜色
        g.setColor(Color.red);
//        g.drawOval(100,100,100,100);//圆
        g.fillOval(100,100,100,100);//实心的圆

        g.setColor(Color.green);
        g.fillRect(150,200,200,200);
        //养成习惯，画笔用完，将它还原到最初的颜色
    }
}

（10）鼠标监听

目的：实现鼠标行为监听

package xyz.dearliu.lesson03;

import java.awt.*;
import java.awt.event.*;
import java.util.ArrayList;
import java.util.Iterator;

/**
 * 鼠标监听事件
 */
public class TestMouseListener {
    public static void main(String[] args) {
        new MyFrame("画图");
    }
}
class MyFrame extends Frame{
    //画画需要画笔，需要监听鼠标当前的位置，需要集合来存储这个点
    ArrayList points;

    public MyFrame(String title){
        super(title);
        setBounds(200,200,400,300);
        //存鼠标点击的坐标
        points = new ArrayList<>();
        //鼠标监听器.正对这个窗口
        this.addMouseListener(new MyMouseListener());
        setVisible(true);
        addWindowListener(new WindowAdapter() {
            @Override
            public void windowClosing(WindowEvent e) {
                System.exit(0);
            }
        });

    }

    @Override
    public void paint(Graphics g) {
        //画画，需要监听鼠标的事件
        Iterator iterator = points.iterator();
        while (iterator.hasNext()){
            Point point =(Point) iterator.next();
            g.setColor(Color.BLUE);
            g.fillOval(point.x,point.y,10,10);
        }
    }


    //适配器模式
    private class MyMouseListener extends MouseAdapter{
        //鼠标 按下，弹起，按住不放
        @Override
        public void mousePressed(MouseEvent e) {
            MyFrame frame = (MyFrame) e.getSource();
            //这个点就是鼠标的点,将这个点加到集合里
            points.add(new Point(e.getX(),e.getY()));
            //每次点击鼠标都要重新画一遍
            frame.repaint();//刷新
        }
    }
}

（11）窗口监听

package xyz.dearliu.lesson03;

import java.awt.*;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;

/**
 * 窗口监听
 */
public class TestWindow {
    public static void main(String[] args) {
        new WindowFrame();
    }
}

class WindowFrame extends Frame{
    public WindowFrame(){
        setVisible(true);
        setBackground(Color.red);
        setBounds(100,100,100,100);
        this.addWindowListener(new WindowAdapter() {
            //关闭窗口
            @Override
            public void windowClosing(WindowEvent e) {
                System.out.println("windowClosing");
                System.exit(0);
            }

            @Override
            public void windowActivated(WindowEvent e) {
                WindowFrame source = (WindowFrame) e.getSource();
                source.setTitle("被激活了");
                System.out.println("windowActivated");
            }

        });
    }
}

（12）键盘监听

package xyz.dearliu.lesson03;

import java.awt.*;
import java.awt.event.KeyAdapter;
import java.awt.event.KeyEvent;

/**
 * 键盘监听
 */
public class TestKeyListener {
    public static void main(String[] args) {
        new KeyFrame();
    }
}

class KeyFrame extends Frame{
    public KeyFrame(){
        setBounds(100,100,300,400);
        setVisible(true);

        this.addKeyListener(new KeyAdapter() {
            @Override
            public void keyTyped(KeyEvent e) {
                super.keyTyped(e);
            }

            //键盘按下
            @Override
            public void keyPressed(KeyEvent e) {
                //获得键盘按下的键是哪一个，当前的码
                int keyCode = e.getKeyCode();
                if (keyCode == KeyEvent.VK_UP){
                    System.out.println("你按下了上键");
                }
            }

            @Override
            public void keyReleased(KeyEvent e) {
                super.keyReleased(e);
            }
        });

    }

}

三、Swing

1. 窗口、面板

package xyz.dearliu.lesson04;

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

public class JFrameDemo02 {
    public static void main(String[] args) {
        new MyJFrame2().init();
    }
}
class MyJFrame2 extends JFrame{
    public void init(){
        this.setVisible(true);
        this.setBounds(10,10,200,300);
        //设置文字 JLable
        JLabel lable = new JLabel("欢迎到来我的世界");
        this.add(lable);
        //让文本标签居中
        lable.setHorizontalAlignment(SwingConstants.CENTER);
        //获取一个容器
        Container container = this.getContentPane();
        container.setBackground(Color.red);
    }
}

2. 弹窗

JDialog，用来被弹出，默认就有关闭实现。

package xyz.dearliu.lesson04;

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

/**
 * 弹窗
 */
public class DialogDemo extends JFrame {

    public DialogDemo(){
        this.setVisible(true);
        this.setSize(700,500);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);//这句话不要也可以，默认点x也会关闭,但是该进程并没有关闭，只是窗口被关掉了。IDEA还是在运行。

        //JFrame 放东西 容器
        Container container = this.getContentPane();
        //绝对布局
        container.setLayout(null);
        //按钮
        JButton jButton = new JButton("点击弹出一个动画框");//创建
        jButton.setBounds(30,30,200,50);

        //点击按钮的时候，弹出一个弹窗
        jButton.addActionListener(new AbstractAction() {//监听器
            @Override
            public void actionPerformed(ActionEvent e) {
                //弹窗
                new MyDialogDemo();
            }
        });

        container.add(jButton);
    }

    public static void main(String[] args) {
        new DialogDemo();
    }
}

class MyDialogDemo extends JDialog{
    public MyDialogDemo() {
        this.setVisible(true);
        this.setBounds(100,100,500,500);
//        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);

        Container container = this.getContentPane();
        container.setLayout(null);
        JLabel label = new JLabel("欢迎来到弹窗的世界");
        label.setBounds(10,10,200,200);
        container.add(label);
    }
}

3. 标签

label
```
new JLabel("xxx");
```

图标 Icon

package xyz.dearliu.lesson04;

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

/**
 * 图标，需要实现类，Frame继承
 */
public class IconDemo extends JFrame implements Icon {
    private int width;
    private int height;

    public IconDemo(){
    }

    public IconDemo(int width, int height){
        this.width = width;
        this.height = height;
    }

    public void init(){
        IconDemo iconDemo = new IconDemo(15,15);
        //图标可以放在标签，也可以放在按钮
        JLabel jLabel = new JLabel("Icon",iconDemo,SwingConstants.CENTER);
        Container container = getContentPane();
        container.add(jLabel);

        this.setVisible(true);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new IconDemo().init();
    }

    @Override
    public void paintIcon(Component c, Graphics g, int x, int y) {
        g.fillOval(x,y,width,height);
    }

    @Override
    public int getIconWidth() {
        return this.width;
    }

    @Override
    public int getIconHeight() {
        return this.height;
    }
}

图片Icon

package xyz.dearliu.lesson04;

import javax.swing.*;
import java.awt.*;
import java.net.URL;

public class ImageIconDemo extends JFrame {
    public ImageIconDemo(){
        //获取图片的地址
        JLabel jLabel = new JLabel("Icon");
        URL url = ImageIconDemo.class.getResource("tx.jpg");

        ImageIcon imageIcon = new ImageIcon(url);
        jLabel.setIcon(imageIcon);
        jLabel.setHorizontalAlignment(SwingConstants.CENTER);

        Container container = getContentPane();
        container.add(jLabel);

        setVisible(true);
        setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
        setBounds(100,100,200,200);
    }

    public static void main(String[] args) {
        new ImageIconDemo();
    }
}

4. 面板

JPanel：

package xyz.dearliu.lesson05;

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

public class JpanelDemo extends JFrame {
    public JpanelDemo(){
        Container container = getContentPane();
        container.setLayout(new GridLayout(2,1,10,10));//后面两个参数的意思是间距
        //网格布局组件数超过其容纳个数会自动优化以容纳这些组件

        JPanel jPanel1 = new JPanel(new GridLayout(1, 3));
        JPanel jPanel2 = new JPanel(new GridLayout(1, 2));
        JPanel jPanel3 = new JPanel(new GridLayout(2, 1));
        JPanel jPanel4 = new JPanel(new GridLayout(3, 2));

        jPanel1.add(new JButton("1"));
        jPanel1.add(new JButton("1"));
        jPanel1.add(new JButton("1"));
        jPanel2.add(new JButton("1"));
        jPanel2.add(new JButton("1"));
        jPanel3.add(new JButton("1"));
        jPanel3.add(new JButton("1"));
        jPanel4.add(new JButton("1"));
        jPanel4.add(new JButton("1"));
        jPanel4.add(new JButton("1"));
        jPanel4.add(new JButton("1"));
        jPanel4.add(new JButton("1"));
        jPanel4.add(new JButton("1"));

        container.add(jPanel1);
        container.add(jPanel2);
        container.add(jPanel3);
        container.add(jPanel4);

        this.setVisible(true);
        this.setSize(500,500);
        this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }

    public static void main(String[] args) {
        new JpanelDemo();
    }
}

JScrollPanel：

package xyz.dearliu.lesson05;

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

public class JScrollDemo extends JFrame {
    public JScrollDemo(){
        Container container = getContentPane();
        //文本域
        JTextArea textArea = new JTextArea(20,50);
        textArea.setText("欢迎来到我的世界");

        //Scroll 面板
        JScrollPane scrollPane = new JScrollPane(textArea);
        container.add(scrollPane);

        setVisible(true);
        setBounds(100,100,300,300);
    }

    public static void main(String[] args) {
        new JScrollDemo();
    }
}

5. 按钮

图片按钮：

package xyz.dearliu.lesson05;

import javax.swing.*;
import java.awt.*;
import java.net.URL;

public class JButtonDemo01 extends JFrame {
    public JButtonDemo01() {
        Container container = getContentPane();
        //图片变成图标
        URL resource = JButtonDemo01.class.getResource("tx.jpg");
        Icon icon = new ImageIcon(resource);

        //把图标放在按钮
        JButton jButton = new JButton();
        jButton.setIcon(icon);
        jButton.setToolTipText("图片按钮");

        container.add(jButton);

        setVisible(true);
        setBounds(100,100,200,200);

    }

    public static void main(String[] args) {
        new JButtonDemo01();
    }
}

单选按钮

package xyz.dearliu.lesson05;

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

public class JButtonDemo03 extends JFrame {
    public JButtonDemo03() {
        Container container = getContentPane();
        //单选框
        JRadioButton jRadioButton1 = new JRadioButton("11111111111");
        JRadioButton jRadioButton2 = new JRadioButton("22222222222");
        JRadioButton jRadioButton3 = new JRadioButton("33333333333");
//        由于单选框只能选择一个，把这三个分在一个组，组中只能选一个
        ButtonGroup buttonGroup = new ButtonGroup();
        buttonGroup.add(jRadioButton1);
        buttonGroup.add(jRadioButton2);
        buttonGroup.add(jRadioButton3);

        container.add(jRadioButton1,BorderLayout.CENTER);
        container.add(jRadioButton2,BorderLayout.NORTH);
        container.add(jRadioButton3,BorderLayout.SOUTH);

        setVisible(true);
        setBounds(100,100,200,200);
    }

    public static void main(String[] args) {
        new JButtonDemo03();
    }
}

复选按钮

package xyz.dearliu.lesson05;

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

public class JButtonDemo03 extends JFrame {
    public JButtonDemo03() {
        Container container = getContentPane();

        JCheckBox jCheckBox1 = new JCheckBox("1111111111");
        JCheckBox jCheckBox2 = new JCheckBox("2222222222");

        container.add(jCheckBox1,BorderLayout.EAST);
        container.add(jCheckBox2,BorderLayout.WEST);

        setVisible(true);
        setBounds(100,100,200,200);
    }

    public static void main(String[] args) {
        new JButtonDemo03();
    }
}

6. 列表

下拉框

box.getSelectedIndex() 返回项数

box.getSelectedItem() 返回内容

package xyz.dearliu.lesson06;

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

public class TestComboboxDemo01 extends JFrame {
    public TestComboboxDemo01(){
        Container container = getContentPane();
        JComboBox<Object> status = new JComboBox<>();
        status.addItem(null);
        status.addItem("正在热映");
        status.addItem("已下架");
        status.addItem("即将上映");
        container.add(status);

        this.setVisible(true);
        this.setSize(500,300);
    }
    public static void main(String[] args) {
        new TestComboboxDemo01();
    }
}

列表框

package xyz.dearliu.lesson06;

import javax.swing.*;
import java.awt.*;
import java.util.Vector;

public class TestComboboxDemo02 extends JFrame {
    public TestComboboxDemo02(){
        Container container = getContentPane();
        //生成列表的内容
//        String[] content = {"1","2","3"};
        //列表中需要放入内容
        Vector vector = new Vector();
        JList jList = new JList(vector);
        container.add(jList);
        vector.add("中国");
        vector.add("美国");
        vector.add("英国");
        this.setVisible(true);
        this.setSize(500,300);
    }
    public static void main(String[] args) {
        new TestComboboxDemo02();
    }
}

应用场景：

选择地区，或者一些单个选项
列表，展示信息，一般是动态扩容

7. 文本框

文本框

package xyz.dearliu.lesson06;

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

public class TestTextDemo01 extends JFrame {

    public TestTextDemo01(){
        Container container = getContentPane();

        JTextField textField = new JTextField("hello");
        JTextField textField2 = new JTextField("world",20);

        container.add(textField,BorderLayout.NORTH);
        container.add(textField2,BorderLayout.SOUTH);

        setVisible(true);
        setSize(500,300);
    }

    public static void main(String[] args) {
        new TestTextDemo01();
    }
}

密码框

package xyz.dearliu.lesson06;

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

public class TestTextDemo02 extends JFrame {

    public TestTextDemo02(){
        Container container = getContentPane();

        JPasswordField passwordField = new JPasswordField();
        passwordField.setEchoChar('*');

        container.add(passwordField);

        setVisible(true);
        setSize(500,300);
    }

    public static void main(String[] args) {
        new TestTextDemo02();
    }
}

文本域

结合面板和滚动条使用

package xyz.dearliu.lesson05;

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

public class JScrollDemo extends JFrame {
    public JScrollDemo(){
        Container container = getContentPane();
        //文本域
        JTextArea textArea = new JTextArea(20,50);
        textArea.setText("欢迎来到我的世界");

        //Scroll 面板
        JScrollPane scrollPane = new JScrollPane(textArea);
        container.add(scrollPane);

        setVisible(true);
        setBounds(100,100,300,300);
    }

    public static void main(String[] args) {
        new JScrollDemo();
    }
}

四、贪吃蛇

帧：如果时间片足够小，就是动画，一秒30帧 60帧。连起来是动画，拆开就是静态的图片。

键盘监听

定时器 Timer

定义数据，画上去，监听事件

1. 代码

package xyz.dearliu.snake;

import javax.swing.*;
import java.net.URL;

/**
 * 数据中心
 */
public class Data {
    //相对路径  tx.jpg
    //绝对路径  / 相当于当前项目
    public static URL headerURl = Data.class.getResource("statics/header.png");
    public static ImageIcon header = new ImageIcon(headerURl);

    public static URL upURl = Data.class.getResource("statics/up.png");
    public static URL downURl = Data.class.getResource("statics/down.png");
    public static URL leftURl = Data.class.getResource("statics/left.png");
    public static URL rightURl = Data.class.getResource("statics/right.png");
    public static ImageIcon up = new ImageIcon(upURl);
    public static ImageIcon down = new ImageIcon(downURl);
    public static ImageIcon left = new ImageIcon(leftURl);
    public static ImageIcon right = new ImageIcon(rightURl);

    public static URL bodyURl = Data.class.getResource("statics/body.png");
    public static ImageIcon body = new ImageIcon(bodyURl);

    public static URL foodURl = Data.class.getResource("statics/food.png");
    public static ImageIcon food = new ImageIcon(foodURl);

}

package xyz.dearliu.snake;

import javax.swing.*;

/**
 * 游戏的主启动类
 */
public class StartGame {
    public static void main(String[] args) {
        JFrame frame = new JFrame("贪吃蛇小游戏");

        //正常游戏界面都应该在面板上
        frame.add(new GamePanel());

        frame.setBounds(10,10,900,720);
        frame.setResizable(false);//窗口大小不可变

        frame.setVisible(true);
        frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
    }
}

package xyz.dearliu.snake;

import javax.swing.*;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.Random;

/**
 * 游戏的面板
 */
public class GamePanel extends JPanel implements KeyListener, ActionListener {
    //定义蛇的数据结构
    int length;//蛇的长度
    int[] snakeX = new int[600];//蛇的X坐标  25*25
    int[] snakeY = new int[500];//蛇的Y坐标  25*25
    String fx;//初始方向

    //食物的坐标
    int foodX;
    int foodY;
    Random random = new Random();

    //游戏当前的状态  开始 停止
    boolean isStart = false; //默认是不开始
    boolean isFail = false;//游戏失败状态

    //定时器 毫秒为单位
    Timer timer = new Timer(100,this);//100ms 执行一次定时器

    int score;//成绩
    
    //初始化方法
    public void init(){
        length = 3;
        snakeX[0] = 100; snakeY[0] = 100;//脑袋的坐标
        snakeX[1] = 75; snakeY[1] = 100;//第一个身体的坐标
        snakeX[2] = 50; snakeY[2] = 100;//第二个身体的坐标
        fx = "R";//初始方向为右
        score = 0;

        foodX = 25 + 25*random.nextInt(34);
        foodY = 75 + 25*random.nextInt(24);
    }

    //构造器
    public GamePanel() {
        init();
        //获得焦点和键盘事件
        setFocusable(true);//获得焦点
        addKeyListener(this);//获得键盘监听事件
        timer.start();//游戏一开始定时器就启动
    }

    //绘制面板,游戏中的所有东西都使用这个画笔来画
    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);//清屏

        //绘制静态的面板
        this.setBackground(Color.WHITE);
        Data.header.paintIcon(this,g,25,11); //头部广告栏
        g.fillRect(25,75,850,600);//黑色的游戏界面

        //画积分
        g.setColor(Color.white);
        g.setFont(new Font("微软雅黑",Font.BOLD,18));
        g.drawString("长度"+length,750,30);
        g.drawString("分数"+score,750,50);

        //画食物
        Data.food.paintIcon(this,g,foodX,foodY);

        //把小蛇画上去
        if (fx.equals("R")){
            Data.right.paintIcon(this,g,snakeX[0],snakeY[0]);//蛇头初始化向右,需要通过方向判断
        }else if (fx.equals("L")){
            Data.left.paintIcon(this,g,snakeX[0],snakeY[0]);//蛇头初始化向右,需要通过方向判断
        }else if (fx.equals("U")){
            Data.up.paintIcon(this,g,snakeX[0],snakeY[0]);//蛇头初始化向右,需要通过方向判断
        }else if (fx.equals("D")){
            Data.down.paintIcon(this,g,snakeX[0],snakeY[0]);//蛇头初始化向右,需要通过方向判断
        }

        for (int i = 1; i < length; i++) {
            Data.body.paintIcon(this,g,snakeX[i],snakeY[i]);//身体
        }

        //游戏状态
        if (isStart == false){
            g.setColor(Color.WHITE);
            //设置字体
            g.setFont(new Font("微软雅黑",Font.BOLD,40));
            g.drawString("按下空格开始游戏！",300,400);
        }
        //游戏失败
        if (isFail){
            g.setColor(Color.red);
            g.setFont(new Font("微软雅黑",Font.BOLD,40));
            g.drawString("游戏失败，按下空格重新开始！",200,400);
        }
    }

    //键盘监听事件
    @Override
    public void keyPressed(KeyEvent e) {
        int keyCode = e.getKeyCode();//获得键盘按键是哪一个
        if (keyCode == KeyEvent.VK_SPACE){
            if (isFail){
                //重新开始
                isFail = false;
                init();
            }else {
                isStart = !isStart; //取反
            }
            repaint();
        }
        //小蛇移动
        if(keyCode == KeyEvent.VK_UP && fx != "D"){
            fx = "U";
        }else if (keyCode == KeyEvent.VK_DOWN && fx != "U"){
            fx = "D";
        }else if (keyCode == KeyEvent.VK_LEFT && fx != "R"){
            fx = "L";
        }else if (keyCode == KeyEvent.VK_RIGHT && fx != "L"){
            fx = "R";
        }
    }

    //事件监听：需要通过固定事件来刷新，1s10次
    @Override
    public void actionPerformed(ActionEvent e) {
        if (isStart && isFail == false){//如果游戏是开始状态，就让小蛇动起来

            //吃食物
            if (snakeX[0] == foodX && snakeY[0] == foodY){
                //长度
                length++;
                //分数+10
                score += 10;
                //再次随机食物
                foodX = 25 + 25*random.nextInt(34);
                foodY = 75 + 25*random.nextInt(24);
            }

            //身体移动
            for (int i = length-1; i >0 ; i--) {//后一节移动到前一节的位置 snakeX[1]  = snakeX[0]
                snakeX[i] = snakeX[i-1];//向前移动一节
                snakeY[i] = snakeY[i-1];
            }

            //走向
            if (fx.equals("R")){
                snakeX[0] = snakeX[0] + 25;
                //边界判断
                if (snakeX[0]>850){
                    snakeX[0] = 25;
                }
            }else if (fx.equals("L")){
                snakeX[0] = snakeX[0] - 25;
                //边界判断
                if (snakeX[0]<25){
                    snakeX[0] = 850;
                }
            }else if (fx.equals("U")){
                snakeY[0] = snakeY[0] - 25;
                //边界判断
                if (snakeY[0]<75){
                    snakeY[0] = 650;
                }
            }else if (fx.equals("D")){
                snakeY[0] = snakeY[0] + 25;
                //边界判断
                if (snakeY[0]>650){
                    snakeY[0] = 75;
                }
            }
            //失败判断，撞到自己就算失败
            for (int i = 1; i < length; i++) {
                if (snakeX[0]==snakeX[i] && snakeY[0]==snakeY[i]){
                    isFail = true;
                }
            }


            repaint();//重画页面
        }
        timer.start();//定时器开始
    }

    @Override
    public void keyReleased(KeyEvent e) {}
    @Override
    public void keyTyped(KeyEvent e) {}
}