Java基础（13）— GUI编程

GUI编程

一 简介

GUI的核心技术：AWT ，Swing

不流行的原因：

1. 因为界面不美观

2. 需要jre环境

为什么我们要学习？

1. 可以写出自己心中想要的一些小工具，外挂等等
2. 工作时候，也可能需要维护到swing界面，概率极小
3. 了解MVC架构，了解监听

二 AWT

2.1 - AWT介绍

1. 它包含了很多类和接口！GUI：图形用户界面编程，Eclipse➡Java编写

2. 元素：窗口，按钮，文本框

3. java.awt

   

2.2 - 组件和容器

• Frame

  package com.gui;
  import java.awt.*;
  //GUI的第一个界面
  public class GuiFrame {
      public static void main(String[] args) {
          //Frame，JDK，看源码
          Frame frame = new Frame("我的第一个java图形界面窗口");
          //设置可见性
          frame.setVisible(true);
          //设置窗口大小
          frame.setSize(500,500);
          //设置背景颜色 Color
          frame.setBackground(new Color(32,92,9));
          //设置初始位置
          frame.setLocation(300,300);
          //设置固定大小
          frame.setResizable(false);
      }
  }
  

  

  • 问题：发现装口关闭不掉，停止Java运行!
  • 回顾封装：

  public class GuiFrame {
      public static void main(String[] args) {
          //展示多个窗口
          new MyFrame(100,100,200,200,Color.darkGray);
          new MyFrame(300,100,200,200,Color.blue);
          new MyFrame(100,300,200,200,Color.red);
          new MyFrame(300,300,200,200,Color.magenta);
      }
  }
  class MyFrame extends Frame{
      static int id = 0;//可能存在多个窗口，我们需要一个计数器
      public MyFrame(int x,int y,int w,int h,Color color){
          super("MyFrame+ " + (++id));//Frame
          setVisible(true);  //设置可见性
          setBounds(x,y,w,h);//设置窗口大小初始位置
          setBackground(color);//设置背景颜色
  
      }
  }
  

  

• Panel 面板

  • 解决了关闭事件

  //Panel 可以看成一个空间，但不能单独存在需要放到Frame中
  public class GuiPanel {
      public static void main(String[] args) {
          Frame frame = new Frame();
          //布局的概念
          Panel panel = new Panel();
          //设置布局
          frame.setLayout(null);
          //坐标
          frame.setBounds(300,300,500,500);
          frame.setBackground(new Color(128, 173, 64));
          //Panel 设置坐标，相对frame
          panel.setBounds(50,50,400,400);
          panel.setBackground(new Color(179, 65, 65));
          //panel加入frame
          frame.add(panel);
          frame.setVisible(true);
          //监听事件，监听窗口关闭事件 System.exit(0)
          /*
          适配器模式
              23种设计模式种的一种
           */
          frame.addWindowListener(new WindowAdapter() {
              //点击关闭的时候需要做的事情
              @Override
              public void windowClosing(WindowEvent e) {
  //                super.windowClosing(e);
                  //结束程序
                  System.exit(0);
              }
          });
      }
  }
  

2.3 - 布局管理器

• 流式布局

  public class GuiFlowLayout {
      public static void main(String[] args) {
          Frame frame = new Frame();
          //组件➡按钮
          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()); 居中
          frame.setLayout(new FlowLayout(FlowLayout.LEFT));//靠左
          frame.setSize(200,200);
          //把按钮添加上去
          frame.add(button1);
          frame.add(button2);
          frame.add(button3);
          //显示
          frame.setVisible(true);
      }
  }
  

• 东西南北中

  public class GuiBorderLayOut {
      public static void main(String[] args) {
          Frame frame = new Frame("BorderLayout");
          //设置button
          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");
          //加入frame
          frame.add(east,BorderLayout.EAST);
          frame.add(west,BorderLayout.WEST);
          frame.add(south,BorderLayout.SOUTH);
          frame.add(north,BorderLayout.NORTH);
          frame.add(center,BorderLayout.CENTER);
          //设置frame
          frame.setSize(200,200);
          frame.setVisible(true);
      }
  }
  

• 表格布局

  public class GuiGridLayout {
      public static void main(String[] args) {
          //设置btn
          Frame frame = new Frame();
          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");
          //加入frame
          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设置
          frame.pack();//Java函数！作用就是优化布局
          frame.setVisible(true);
      }
  }
  

• 界面练习（Frame + Panel + Button）

  

  public class GuiLayoutTest {
      public static void main(String[] args) {
          Frame frame = new Frame("界面练习");
          frame.setSize(400,300);
          frame.setLocation(300,400);
          frame.setBackground(Color.GRAY);
          frame.setVisible(true);
          //上下两部分（表格布局上下-两行一列）
          frame.setLayout(new GridLayout(2,1));
          //四个面板
          //上面
          Panel p1 = new Panel(new BorderLayout());
          Panel p2 = new Panel(new GridLayout(2,1));
          p1.add(new Button("East1"),BorderLayout.EAST);
          p1.add(new Button("West1"),BorderLayout.WEST);
          p2.add(new Button("p2-btn-1"));
          p2.add(new Button("p2-btn-2"));
          p1.add(p2,BorderLayout.CENTER);
          frame.add(p1);
          //下面
          Panel p3 = new Panel(new BorderLayout());
          Panel p4 = new Panel(new GridLayout(2,2));
          p3.add(new Button("East2"),BorderLayout.EAST);
          p3.add(new Button("West2"),BorderLayout.WEST);
          for (int i = 1; i <= 4; i++) {
              p4.add(new Button("p4-btn-"+i));
          }
          p3.add(p4);
          frame.add(p3);
          //关闭监听
          frame.addWindowListener(new WindowAdapter() {
              @Override
              public void windowClosing(WindowEvent e) {
                  System.exit(0);
              }
          });
      }
  }
  

2.4 - 事件监听

• 按钮监听

  public class GuiActionEvent {
      public static void main(String[] args) {
          //按下按钮，出发一些事件
          Frame frame = new Frame();
          Button button = new Button();
          //因为，addActionListener()需要一个ActionListener，所以我们构造一个MyActionListener implements ActionListener
          MyActionListener myActionListener = new MyActionListener();
          button.addActionListener(myActionListener);
          frame.add(button,BorderLayout.CENTER);
          frame.pack();
          frame.setVisible(true);
          windowClosing(frame);
      }
      //关闭窗体事件监听
      public static void windowClosing(Frame frame){
          frame.addWindowListener(new WindowAdapter() {
              @Override
              public void windowClosing(WindowEvent e) {
                  System.exit(0);
              }
          });
      }
  }
  //事件监听
  class MyActionListener implements ActionListener{
      @Override
      public void actionPerformed(ActionEvent e) {
          System.out.println("AAA");
      }
  }
  

• 多个按钮共享一个监听事件

  public class GuiActionEvent {
      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 startBtn = new Button("start");
          Button stopBtn = new Button("stop");
          /*
          可以显示的定义出发会返回的命令，如果不显示定义，则会走默认的值
          可以多个按钮只写一个监听类，监听类共用。
           */
          startBtn.setActionCommand("startBtn-start");
          stopBtn.setActionCommand("stopBtn-stop");
  
          MyMonitor myMonitor = new MyMonitor();
          startBtn.addActionListener(myMonitor);
          stopBtn.addActionListener(myMonitor);
  
          frame.add(startBtn,BorderLayout.NORTH);
          frame.add(stopBtn,BorderLayout.SOUTH);
          frame.pack();
          frame.setVisible(true);
          windowClosing(frame);
  
      }
      //关闭窗体事件监听
      public static void windowClosing(Frame frame){
          frame.addWindowListener(new WindowAdapter() {
              @Override
              public void windowClosing(WindowEvent e) {
                  System.exit(0);
              }
          });
      }
  }
  //事件监听
  class MyMonitor implements ActionListener{
      @Override
      public void actionPerformed(ActionEvent e) {
          //e.getActionCommand() 获取按钮的信息
          System.out.println("按钮被点击了：msg ➡ "+ e.getActionCommand());
          if(e.getActionCommand().equals("startBtn-start")){
              System.out.println("开始播放");//根据e.getActionCommand()的返回值不同会有不同的操作
          }
          if(e.getActionCommand().equals("stopBtn-stop")){
              System.out.println("停止播放");
          }
      }
  }
  

2.5 - 输入框TextField监听

• 监听文本框种的文本

  public class GuiTextField {
      public static void main(String[] args) {
          //启动
          new MyFrame();
      }
  }
  class MyFrame extends Frame{
      public MyFrame(){
          TextField textField = new TextField();
          add(textField);
          //按下Enter,就会触发这个监听文本框输入的文字
          textField.addActionListener(new MyActionListener());
          //设置编码
          textField.setEchoChar('*');
          pack();
          setVisible(true);
      }
  }
  class MyActionListener implements ActionListener{
      @Override
      public void actionPerformed(ActionEvent e) {
          TextField field = (TextField) e.getSource();//获得一些资源,返回一个对象
          System.out.println(field.getText());//获得输入框的文本
          field.setText("");//回车清空，null是对象，”“是字符串
      }
  }
  

2.6 - 简易计算器，组合+内部类回顾

• oop原则，组合 > 继承

  class A extends B{
      //继承
  }
  class A{
      public B b;//组合，减小耦合性
  }
  

• 目前的计算器

  public class GuiCalc {
      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);
          TextField num2 = new TextField(10);
          TextField num3 = new TextField(20);
          //一个标签
          Label label = new Label("+");
          //一个按钮
          Button button = new Button("=");
          button.addActionListener(new CalculatorListener(num1,num2,num3));
          //布局
          setLayout(new FlowLayout());
          add(num1);
          add(label);
          add(num2);
          add(button);
          add(num3);
          pack();
          setVisible(true);
      }
  }
  //监听器类
  class CalculatorListener implements ActionListener{
      //获取三个变量
      private TextField num1,num2,num3;
      public CalculatorListener(TextField num1,TextField num2,TextField num3 ){
          this.num1 = num1;
          this.num2 = num2;
          this.num3 = num3;
      }
      @Override
      public void actionPerformed(ActionEvent e) {
          //1.获得num1 num2
          int n1 = Integer.parseInt(num1.getText());
          int n2 = Integer.parseInt(num2.getText());
          //2.将这个值运算后，放到第三个框
          num3.setText(""+(n1+n2));
          //3.清空前两个框
          num1.setText("");
          num2.setText("");
      }
  }
  

• 组合的方式，完全改造为oop

  public class GuiCalc {
      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(){
          //组件
          num1 = new TextField(10);//字符数
          num2 = new TextField(10);
          num3 = new TextField(20);
          Label label = new Label("+");
          Button button = new Button("=");
          //监听
          button.addActionListener(new CalculatorListener(this));
          //布局
          setLayout(new FlowLayout());
          add(num1);
          add(label);
          add(num2);
          add(button);
          add(num3);
          pack();
          setVisible(true);
      }
  }
  //监听器类
  class CalculatorListener implements ActionListener{
      //获取计算器这个对象，在一个类种组合另一个类
      Calculator calculator = null;
      public CalculatorListener(Calculator calculator){
          this.calculator = calculator;
      }
      @Override
      public void actionPerformed(ActionEvent e) {
          //1.获得num1 num2
          int n1 = Integer.parseInt(calculator.num1.getText());
          int n2 = Integer.parseInt(calculator.num2.getText());
          //2.将这个值运算后，放到第三个框
          calculator.num3.setText(""+(n1+n2));
          //3.清空前两个框
          calculator.num1.setText("");
          calculator.num2.setText("");
      }
  }
  

• 内部类

  • 更好的包装

  public class GuiCalc {
      public static void main(String[] args) {
          Calculator calculator = new Calculator();
          calculator.loadFrame();
          closing(calculator);
      }
      public static void closing(Frame frame){
          frame.addWindowListener(new WindowAdapter() {
              @Override
              public void windowClosing(WindowEvent e) {
                  System.exit(0);
              }
          });
      }
  }
  //计算器类
  class Calculator extends Frame{
      //属性
      TextField num1,num2,num3;
      //方法
      public void loadFrame(){
          //组件
          num1 = new TextField(10);//字符数
          num2 = new TextField(10);
          num3 = new TextField(20);
          Label label = new Label("+");
          Button button = new Button("=");
          //监听
          button.addActionListener(new CalculatorListener());
          //布局
          setLayout(new FlowLayout());
          add(num1);
          add(label);
          add(num2);
          add(button);
          add(num3);
          pack();
          setVisible(true);
      }
      //监听器类
      //内部类最大的好处，就是可以畅通无阻的访问外部类的属性喝方法！
      private class CalculatorListener implements ActionListener{
          @Override
          public void actionPerformed(ActionEvent e) {
              //1.获得num1 num2
              int n1 = Integer.parseInt(num1.getText());
              int n2 = Integer.parseInt(num2.getText());
              //2.将这个值运算后，放到第三个框
              num3.setText(""+(n1+n2));
              //3.清空前两个框
              num1.setText("");
              num2.setText("");
          }
      }
  }
  

2.7 - 画笔

• 简单的操作

  public class GuiPaint {
      public static void main(String[] args) {
          new MyPaint().loadFrame();
      }
  }
  class MyPaint extends Frame{
      public void loadFrame(){
          setBounds(200,200,600,400);
          setVisible(true);
      }
      @Override
      public void paint(Graphics g) {
          //画笔需要有颜色，可以画画
          g.setColor(Color.RED);
  //        g.drawOval(100,100,100,100);//空心圆⚪
          g.fillOval(100,100,100,100);//实心圆
          g.setColor(Color.GREEN);
          g.fillRect(150,200,200,200);//实心矩形
          //养成习惯，画笔用完将他还原到最初的颜色
      }
  }
  

2.8 - 鼠标监听

• 目的：想要实现鼠标画画！

  

  //鼠标监听事件
  public class GuiMouseListener {
      public static void main(String[] args) {
          new MyPaintFrame("画图");
      }
  }
  //自己的Frame
  class MyPaintFrame 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 MyPaintFrame(String title){
          super(title);
          setBounds(200,200,400,300);
          //存鼠标的点
          points = new ArrayList<>();
          setVisible(true);
          //鼠标监听器，正对这个窗口
          this.addMouseListener(new MyMouseListener());
      }
      @Override
      public void paint(Graphics g) {
          //画画，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);
          }
      }
      //添加一个点到界面上面
      public void addPaint(Point point){
          points.add(point);
      }
      //适配器模式
      private class MyMouseListener extends MouseAdapter {
          //鼠标： 按压，弹起，按住不放
          @Override//按压
          public void mousePressed(MouseEvent e) {
              MyPaintFrame myPaintFrame = (MyPaintFrame) e.getSource();
              //这里点击的时候就会在界面产生一个点！
              //这个点就是鼠标的点
              myPaintFrame.addPaint(new Point(e.getX(),e.getY()));
  
              //每次点击鼠标都需要重新画一次
              myPaintFrame.repaint();//刷新
          }
      }
  }
  

2.9 - 窗口监听

• 最常用窗口关闭（windowClosing）与激活（windowActivated）

  public class GuiWindowListener {
      public static void main(String[] args) {
          new WindowFrame();
      }
  }
  class WindowFrame extends Frame{
      public WindowFrame(){
          setBackground(Color.BLUE);
          setBounds(100,100,200,200);
          setVisible(true);
          this.addWindowListener(new WindowAdapter() {
              //关闭窗口
              @Override
              public void windowClosing(WindowEvent e) {
                  System.out.println("windowClosing");
                  System.exit(0);
              }
              //激活
              @Override
              public void windowActivated(WindowEvent e) {
                  WindowFrame source = (WindowFrame) e.getSource();
                  source.setTitle("被激活了");
                  System.out.println("windowActivated");
              }
          });
      }
  }
  

2.10 - 键盘监听

• 根据按下不同操作，产生不同结果

  public class GuiKeyListener {
      public static void main(String[] args) {
          new KeyFrame();
      }
  }
  class KeyFrame extends Frame{
      public KeyFrame(){
          setBounds(100,200,300,400);
          setVisible(true);
          this.addKeyListener(new KeyAdapter() {
              @Override
              public void keyPressed(KeyEvent e) {
                  //键盘按下的键是哪个,当前的码
                  int keyCode = e.getKeyCode();//不需要记录这个16进制的值，直接使用静态属性 VK_xxx
                  System.out.println(keyCode);
                  if(keyCode == KeyEvent.VK_UP){
                      System.out.println("你按下了上键！");
                  }
              }
          });
      }
  }
  

三 Swing

3.1 - 窗口，面板

• 第一个案例（JFrame，JLabel）

  public class JFrameDemo {
      public static void main(String[] args) {
          //建立一个窗口
          new MyJFrame().init();
      }
  }
  class MyJFrame extends JFrame{
      public void init(){
          this.setBounds(10,10,200,300);
          this.setVisible(true);
          JLabel label = new JLabel("欢迎来到java世界");
          this.add(label);
          //让文本标签居中，设置水平对齐
          label.setHorizontalAlignment(SwingConstants.CENTER);
          //获取一个容器
          Container container = this.getContentPane();
          container.setBackground(Color.CYAN);
      }
  }
  

3.2 - 弹窗

• JDialog，绑定JButton事件

  //主窗口
  public class DialogDemo extends JFrame {
      public static void main(String[] args) {
          new DialogDemo();
      }
      public DialogDemo() {
          this.setVisible(true);
          this.setSize(700,500);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
          //JFrame放东西 ➡ 容器
          Container container = this.getContentPane();
          //绝对布局
          container.setLayout(null);
          //按钮
          JButton button = new JButton("点击弹出一个对话框");//创建
          button.setBounds(30,30,200,50);
          container.add(button);
          //点击按钮的时候，弹出一个弹窗
          button.addActionListener(new ActionListener() {//监听器
              @Override
              public void actionPerformed(ActionEvent e) {
                  //弹框
                  new MyDialog();
              }
          });
      }
  }
  //弹窗的窗口
  class MyDialog extends JDialog{
      public MyDialog(){
          this.setVisible(true);
          this.setBounds(100,100,500,500);
          Container container = this.getContentPane();
          container.setLayout(null);
          container.add(new Label("Welcome to the Java world"));
      }
  }
  

3.3 - 标签

• Label

  new JLabel("xxx");
  

• 图标 Icon

  //图标，需要实现类，Frame继承
  public class IconDemo extends JFrame implements Icon {
      private int width;
      private int height;
      /*
      构造无参/有参
       */
      public IconDemo(){}
      public IconDemo(int width,int height){
          this.width = width;
          this.height = height;
      }
      public void init(){
          IconDemo icon = new IconDemo(15, 15);
          //图标放到标签上，也可以放到按钮上！
          JLabel label = new JLabel("icon test", icon, SwingConstants.CENTER);
          Container container = getContentPane();
          container.add(label);
          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（logo）

  //图片(logo)
  public class ImageIconDemo extends JFrame {
      public ImageIconDemo() {
          JLabel label = new JLabel("ImageIcon");
          //获取图片的地址
          URL url = ImageIconDemo.class.getResource("tree.png");
          ImageIcon imageIcon = new ImageIcon(url);//命名不要冲突
          label.setIcon(imageIcon);
          label.setHorizontalAlignment(SwingConstants.CENTER);
          Container container = getContentPane();
          container.add(label);
          setVisible(true);
          setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
          setBounds(100,200,400,400);
      }
      public static void main(String[] args) {
          new ImageIconDemo();
      }
  }
  

3.4 - 面板

• JPanel

  public class JPanelDemo extends JFrame {
      public static void main(String[] args) {
          new JPanelDemo();
      }
      public JPanelDemo() {
          Container container = this.getContentPane();
          container.setLayout(new GridLayout(2,1,10,10));//后面的参数的意思是间距
          JPanel panel1 = new JPanel(new GridLayout(1, 3));
          JPanel panel2 = new JPanel(new GridLayout(1, 2));
          JPanel panel3 = new JPanel(new GridLayout(2, 1));
          JPanel panel4 = new JPanel(new GridLayout(3, 2));
          panel1.add(new JButton("1"));
          panel1.add(new JButton("1"));
          panel1.add(new JButton("1"));
          panel2.add(new JButton("2"));
          panel2.add(new JButton("2"));
          panel3.add(new JButton("3"));
          panel3.add(new JButton("3"));
          panel4.add(new JButton("4"));
          panel4.add(new JButton("4"));
          panel4.add(new JButton("4"));
          panel4.add(new JButton("4"));
          panel4.add(new JButton("4"));
          panel4.add(new JButton("4"));
          container.add(panel1);
          container.add(panel2);
          container.add(panel3);
          container.add(panel4);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
          this.setVisible(true);
          this.setSize(500,500);
      }
  }
  

• JscrollPanel

  public class JScrollDemo extends JFrame {
      public JScrollDemo(){
          Container container = this.getContentPane();
          //文本域
          JTextArea textArea = new JTextArea(20,50);
          textArea.setText("欢迎学习Java");
          //Scroll面板
          JScrollPane scrollPane = new JScrollPane(textArea);
          container.add(scrollPane);
          this.setVisible(true);
          this.setBounds(100,100,300,350);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new JScrollDemo();
      }
  }
  

3.5 - 按钮

• 图片按钮

  public class JButtonDemo extends JFrame {
      public JButtonDemo(){
          Container container = this.getContentPane();
          //将图片编程图标
          URL resource = JButtonDemo.class.getResource("tree.png");
          Icon icon = new ImageIcon(resource);
          //把图标放到按钮上
          JButton button = new JButton();
          button.setIcon(icon);
          button.setToolTipText("图片按钮！");
          //加入容器
          container.add(button);
  
          this.setVisible(true);
          this.setSize(500,300);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new JButtonDemo();
      }
  }
  

• 单选框，圆形

  public class JButtonDemo extends JFrame {
      public JButtonDemo(){
          Container container = this.getContentPane();
          //将图片编程图标
          URL resource = JButtonDemo.class.getResource("tree.png");
          Icon icon = new ImageIcon(resource);
          //单选框
          JRadioButton radioButton01 = new JRadioButton("JRadioButton01");
          JRadioButton radioButton02 = new JRadioButton("JRadioButton02");
          JRadioButton radioButton03 = new JRadioButton("JRadioButton03");
          //由于单选框只能选一个，一般分成一个组。
          ButtonGroup group = new ButtonGroup();
          group.add(radioButton01);
          group.add(radioButton02);
          group.add(radioButton03);
          //上中下
          container.add(radioButton01,BorderLayout.CENTER);
          container.add(radioButton02,BorderLayout.SOUTH);
          container.add(radioButton03,BorderLayout.NORTH);
          this.setVisible(true);
          this.setSize(500,300);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new JButtonDemo();
      }
  }
  

• 多选框，方块

  public class JButtonDemo extends JFrame {
      public JButtonDemo(){
          Container container = this.getContentPane();
          //将图片编程图标
          URL resource = JButtonDemo.class.getResource("tree.png");
          Icon icon = new ImageIcon(resource);
          //单选框
          JCheckBox checkBox01 = new JCheckBox("checkBox01");
          JCheckBox checkBox02 = new JCheckBox("checkBox02");
          JCheckBox checkBox03 = new JCheckBox("checkBox03");
          //多选不需要分组
          //上中下
          container.add(checkBox01,BorderLayout.CENTER);
          container.add(checkBox02,BorderLayout.SOUTH);
          container.add(checkBox03,BorderLayout.NORTH);
          this.setVisible(true);
          this.setSize(500,300);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new JButtonDemo();
      }
  }
  

3.6 - 列表

• 下拉框

  public class ComboboxDemo extends JFrame {
      public ComboboxDemo(){
          Container container = this.getContentPane();
          JComboBox 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);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new ComboboxDemo();
      }
  }
  

• 列表框

  public class ComboboxDemo extends JFrame {
      public ComboboxDemo(){
          Container container = this.getContentPane();
          //生成列表的内容
  //        String[] contents = {"1","2","3"};
          Vector contents = new Vector();
          contents.add("张三");
          contents.add("李四");
          contents.add("王五");
          //列表需要放内容
          JList list = new JList(contents);
          container.add(list);
          this.setVisible(true);
          this.setSize(500,300);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new ComboboxDemo();
      }
  }
  

• 应用场景

  • 下拉，选择地区，或者一些单项选项
  • 列表，展示信息，一般是动态扩容

3.7 - 文本框

• 文本框

  public class TextDemo extends JFrame {
      public TextDemo(){
          Container container = this.getContentPane();
          JTextField field01 = new JTextField("hello");
          JTextField field02 = new JTextField("world",20);
          container.add(field01,BorderLayout.NORTH);
          container.add(field02,BorderLayout.SOUTH);
          this.setVisible(true);
          this.setSize(500,300);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new TextDemo();
      }
  }
  

• 密码框

  public class TextDemo extends JFrame {
      public TextDemo(){
          Container container = this.getContentPane();
          //面板
          JPasswordField field = new JPasswordField();//****
          field.setEchoChar('*');
          container.add(field);
          this.setVisible(true);
          this.setSize(500,300);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new TextDemo();
      }
  }
  

• 文本域

  public class JScrollDemo extends JFrame {
      public JScrollDemo(){
          Container container = this.getContentPane();
          //文本域
          JTextArea textArea = new JTextArea(20,50);
          textArea.setText("欢迎学习Java");
          //Scroll面板
          JScrollPane scrollPane = new JScrollPane(textArea);
          container.add(scrollPane);
          this.setVisible(true);
          this.setBounds(100,100,300,350);
          this.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
      }
      public static void main(String[] args) {
          new JScrollDemo();
      }
  }
  

贪吃蛇

• 帧，如果时间片足够小，就是动画，一秒30帧， 60帧通过人眼跟30帧差不多。连起来是动画，拆开就是静态的图片！

• 键盘监听

• 定时器 Timer

  //数据中心
  public class Data {
      private static URL headerURL = Data.class.getResource("statics/header.png");
      public static ImageIcon header = new ImageIcon(headerURL);
      private static URL upURL = Data.class.getResource("statics/up.png");
      private static URL downURL = Data.class.getResource("statics/down.png");
      private static URL leftURL = Data.class.getResource("statics/left.png");
      private 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);
      private static URL bodyURL = Data.class.getResource("statics/body.png");
      public static ImageIcon body = new ImageIcon(bodyURL);
      private static URL foodURL = Data.class.getResource("statics/food.png");
      public static ImageIcon food = new ImageIcon(foodURL);
  }
  //游戏的主启动类
  public class GameStart {
      public static void main(String[] args) {
          JFrame frame = new JFrame();
          frame.setBounds(10,10,900,720);
          frame.setResizable(false);//窗口大小不可变
          frame.setDefaultCloseOperation(WindowConstants.EXIT_ON_CLOSE);
          //正常游戏界面都应该在面板上！
          frame.add(new GamePanel());
          frame.setVisible(true);
      }
  }
  //游戏的面板➡主操作
  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*30
      int[] snakeY = new int[500];//蛇的Y坐标 25*25
      String direction;//初始方向
      //是否失败
      boolean isFail = false; //失败状态
      //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; //默认停止
      //定时器，以毫秒为单位 1000ms = 1s
      Timer timer = new Timer(100,this);//100毫秒执行一次
      //积分
      int score;
      public GamePanel(){
          init();
          //获得焦点和键盘事件
          this.setFocusable(true);//获得焦点事件
          this.addKeyListener(this);//获得键盘监听事件
          timer.start();//游戏一开始就启动
          score = 0;
      }
      //初始化方法
      public void init(){
          length = 3;
          snakeX[0] = 100; snakeY[0] = 100; //头坐标
          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
          direction = "R"; //初始方向向右
          //把食物随机分布在界面上
          foodX = 25 + 25*random.nextInt(34);
          foodY = 75 + 25*random.nextInt(24);
      }
      //绘制面板，我们游戏中的所有东西，都是用这个画笔
      @Override
      protected void paintComponent(Graphics g) {
          super.paintComponent(g);//清屏
          this.setBackground(Color.WHITE);//背景白色，默认
          //绘制静态面板
          Data.header.paintIcon(this,g,25,11);//头部广告栏画上去
          g.fillRect(25,75,850,600);//默认的游戏界面
          //画积分
          g.setColor(Color.WHITE);
          g.setFont(new Font("微软雅黑",Font.BOLD,18));//设置字体
          g.drawString("长度 "+length,750,35);
          g.drawString("分数 "+score,750,50);
          //画食物
          Data.food.paintIcon(this,g,foodX,foodY);
          //把小蛇画上去
          if(direction.equals("R")){
              Data.right.paintIcon(this,g,snakeX[0],snakeY[0]); //蛇头初始化向右，通过方向来判断
          }else if(direction.equals("L")){
              Data.left.paintIcon(this,g,snakeX[0],snakeY[0]); //蛇头初始化向右，通过方向来判断
          }else if(direction.equals("U")){
              Data.up.paintIcon(this,g,snakeX[0],snakeY[0]); //蛇头初始化向右，通过方向来判断
          }else if(direction.equals("D")){
              Data.down.paintIcon(this,g,snakeX[0],snakeY[0]); //蛇头初始化向右，通过方向来判断
          }
          for (int i = 1; i < length; i++) {
              Data.body.paintIcon(this,g,snakeX[i],snakeY[i]); //初始化第一个身体
          }
          //游戏状态
          if(isStart==false) {
              g.setColor(Color.WHITE);
              g.setFont(new Font("微软雅黑", Font.BOLD, 40));//设置字体
              g.drawString("按下空格键开始游戏", 300, 300);
          }
          //失败状态
          if(isFail){
              g.setColor(Color.RED);
              g.setFont(new Font("微软雅黑",Font.BOLD,40));//设置字体
              g.drawString("游戏失败，按下空格重新开始",300,300);
          }
      }
      //键盘监听事件
      @Override
      public void keyPressed(KeyEvent e) {
          int keyCode = e.getKeyCode();//获得键盘按键时哪个
          if(keyCode == KeyEvent.VK_SPACE){//空格
              if(isFail){
                  //重新开始
                  isFail = false;
                  init();
              }else{
                  isStart = !isStart;//取反
              }
              repaint();
          }
          //小蛇移动
          if(keyCode == KeyEvent.VK_UP){
              direction = "U";
          }else if(keyCode == KeyEvent.VK_DOWN){
              direction = "D";
          }else if(keyCode == KeyEvent.VK_LEFT){
              direction = "L";
          }else if(keyCode == KeyEvent.VK_RIGHT){
              direction = "R";
          }
      }
      //事件监听 ➡ 需要通过固定事件来刷新，1s = 10次
      @Override
      public void actionPerformed(ActionEvent e) {
          if(isStart && !isFail){//如果游戏时开始状态，就让小蛇动起来
              //吃食物
              if(snakeX[0] == foodX && snakeY[0] == foodY){
                  length++;//长度+1
                  score = score + 10;//积分+10
                  //再次随机分布食物
                  foodX = 25 + 25*random.nextInt(34);
                  foodY = 75 + 25*random.nextInt(24);
              }
              //移动
              for (int i = length - 1; i > 0; i--) {//后一节移动前一节的位置
                  snakeX[i] = snakeX[i-1];
                  snakeY[i] = snakeY[i-1];
              }
              if(direction.equals("R")){
                  snakeX[0] = snakeX[0]+25;
                  if(snakeX[0] > 850){snakeX[0] = 25;}
              }else if(direction.equals("L")){
                  snakeX[0] = snakeX[0]-25;
                  if(snakeX[0] < 25){snakeX[0] = 850;}
              }else if(direction.equals("U")){
                  snakeY[0] = snakeY[0]-25;
                  if(snakeY[0] < 75){snakeY[0] = 650;}
              }else if(direction.equals("D")){
                  snakeY[0] = snakeY[0]+25;
                  if(snakeY[0] > 650 ){snakeY[0] = 75;}
              }
              //失败判定，撞到自己算失败
              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();//定时器开启
      }
      @Override
      public void keyReleased(KeyEvent e) { }
      @Override
      public void keyTyped(KeyEvent e) { }
  }
  

• 所需附件