【JavaGUI】JavaGUI入门到小游戏实战(2)

前言：

本文内容：事件监听、输入框事件监听、简易计算器和回顾组合内部类、画笔paint、鼠标监听事件和模拟画图工具、窗口监听事件、键盘监听事件

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事件监听

• 当某个事情发生的时候，干什么？

  package com.jokerdig.lesson2;
  
  import java.awt.*;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  import java.awt.event.WindowAdapter;
  import java.awt.event.WindowEvent;
  
  /**
   * @author Joker大雄
   * @data 2021/8/17 - 21:14
   **/
  public class TestActionEvent {
      public static void main(String[] args) {
          //按下按钮，触发事件
          Frame frame = new Frame();
          Button button = new Button();
          //因为，addActionListener()需要一个ActionListener,我们需要构造ActionListener
          MyActionListener myActionListener = new MyActionListener();
          button.addActionListener(myActionListener);
  
          frame.add(button,BorderLayout.CENTER);
          frame.pack();
          frame.setVisible(true);
          windowClose(frame);//关闭窗口
      }
  
      //关闭窗口
      private static void windowClose(Frame frame){
          frame.addWindowListener(new WindowAdapter() {
              @Override
              public void windowClosing(WindowEvent e) {
                  //关闭窗口
                  System.exit(0);
              }
          });
      }
  }
  //按钮事件监听
  class MyActionListener implements ActionListener{
  
   // 重写方法
      @Override
      public void actionPerformed(ActionEvent e) {
          System.out.println("按钮点击事件");
      }
  }

• 让两个按钮共用一个事件

  package com.jokerdig.lesson2;
  
  import java.awt.*;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  
  /**
   * @author Joker大雄
   * @data 2021/8/17 - 21:25
   **/
  public class TestActionEventTwo {
      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
          button2.setActionCommand("定义事件");
  
          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) {
          //
          System.out.println("按钮被点击了:msg"+e.getActionCommand());
      }
  }

输入框事件监听

package com.jokerdig.lesson2;

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

/**
 * @author Joker大雄
 * @data 2021/8/17 - 21:39
 **/
public class TestText01 {
    public static void main(String[] args) {
        //启动
        new MyFrame();
    }
}

class MyFrame extends Frame {
    public MyFrame(){
        TextField textField = new TextField();
        add(textField);
        //监听这个文本框输入的文字
        MyActionListener2 maction = new MyActionListener2();
        textField.addActionListener(maction);
        //设置替换编码
        textField.setEchoChar('*');
        setVisible(true);
        pack();
    }
}

class MyActionListener2 implements ActionListener{


    @Override
    public void actionPerformed(ActionEvent e) {
        //获得一些资源
       TextField text1=(TextField) e.getSource();
       text1.getText();//获得输入框文本
        System.out.println(text1.getText());
        text1.setText("");
    }
}

简易计算器、回顾组合内部类

• opp原则：组合大于继承

  class A extends B{
      
  }
  class A extends B{
      //A用B功能，把B私有进来，降低耦合
      private B b;
  }

制作简易计算器：

• 示例图：

  

• 效果图

  

• 代码：

  package com.jokerdig.lesson2;
  
  import java.awt.*;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  import java.awt.event.WindowAdapter;
  import java.awt.event.WindowEvent;
  
  /**
   * @author Joker大雄
   * @data 2021/8/17 - 21:58
   **/
  //简易计算器
  public class TestClac {
      public static void main(String[] args) {
          //启动
          new Calculator().loadFrame();
      }
  }
  //计算器类
  class Calculator extends Frame{
      //属性
      TextField text1,text2,text3;
      //方法
      public void loadFrame(){
          Frame f=new Frame("简易计算器");
          //3个文本框
          text1 = new TextField(10);//字符数
          text2 = new TextField(10);//字符数
          text3 = new TextField(20);//字符数
  
          //1 个按钮
          Button button = new Button("=");
          //按钮监听事件
          button.addActionListener(new MyCalculatorListener(this));
          //1 个标签
          Label label = new Label("+");
          //布局
          f.setLayout(new FlowLayout());//流式布局
  
          f.add(text1);
          f.add(label);
          f.add(text2);
          f.add(button);
          f.add(text3);
          f.pack();//自适应
          f.setVisible(true);//显示布局
          closeWindow(f);//关闭窗口
      }
  
       //关闭窗口
      public static void closeWindow(Frame frame){
          frame.addWindowListener(new WindowAdapter() {
  
              @Override
              public void windowClosing(WindowEvent e) {
                  //关闭
                  System.exit(0);
              }
          });
      }
  }
  
  //监听器类
  class MyCalculatorListener implements ActionListener{
  
      /*用构造器获取三个变量
        private  TextField text1,text2,text3;
      */
      //获取计算器对象,在一个类中组合另一个类
      Calculator cal = null;
      public MyCalculatorListener(Calculator cal) {
          this.cal = cal;
      }
  
      @Override
      public void actionPerformed(ActionEvent e) {
          //1.获得加数和被加数
          int t1=Integer.parseInt(cal.text1.getText());
          int t2=Integer.parseInt(cal.text2.getText());
          //2.把值运算后放入第三个框
          cal.text3.setText(""+(t1+t2));
          //3.清楚前两个框
          cal.text1.setText("");
          cal.text2.setText("");
      }
  }

内部类优势：

• 更好的包装

• 更畅通的访问外部类

  package com.jokerdig.lesson2;
  
  import java.awt.*;
  import java.awt.event.ActionEvent;
  import java.awt.event.ActionListener;
  import java.awt.event.WindowAdapter;
  import java.awt.event.WindowEvent;
  
  /**
   * @author Joker大雄
   * @data 2021/8/17 - 21:58
   **/
  //简易计算器
  public class TestClac {
      public static void main(String[] args) {
          //启动
          new Calculator().loadFrame();
      }
  }
  //计算器类
  class Calculator extends Frame{
      //属性
      TextField text1,text2,text3;
      //方法
      public void loadFrame(){
          Frame f=new Frame("简易计算器");
          //3个文本框
          text1 = new TextField(10);//字符数
          text2 = new TextField(10);//字符数
          text3 = new TextField(20);//字符数
  
          //1 个按钮
          Button button = new Button("=");
          //按钮监听事件
          button.addActionListener(new MyCalculatorListener());
          //1 个标签
          Label label = new Label("+");
          //布局
          f.setLayout(new FlowLayout());//流式布局
  
          f.add(text1);
          f.add(label);
          f.add(text2);
          f.add(button);
          f.add(text3);
          f.pack();//自适应
          f.setVisible(true);//显示布局
          closeWindow(f);//关闭窗口
      }
  
      //关闭窗口
      public static void closeWindow(Frame frame){
          frame.addWindowListener(new WindowAdapter() {
  
              @Override
              public void windowClosing(WindowEvent e) {
                  //关闭
                  System.exit(0);
              }
          });
      }
      //监听器类
      //使用内部类简化代码
     private class MyCalculatorListener implements ActionListener{
  
          @Override
          public void actionPerformed(ActionEvent e) {
              //1.获得加数和被加数
              int t1=Integer.parseInt(text1.getText());
              int t2=Integer.parseInt(text2.getText());
              //2.把值运算后放入第三个框
              text3.setText(""+(t1+t2));
              //3.清楚前两个框
              text1.setText("");
              text2.setText("");
          }
      }
  }

画笔Paint

package com.jokerdig.lesson3;

import java.awt.*;

/**
 * @author Joker大雄
 * @data 2021/8/17 - 22:45
 **/
public class TestPaint {
    public static void main(String[] args) {
        new MyPaint().loadFrame();
    }
}
//画笔类
class MyPaint extends Frame{

    public void loadFrame(){
        setBounds(200,200,600,500);
        setVisible(true);
    }
    
    //画笔
    public void paint(Graphics g){
       //画笔需要颜色，可以绘画
        g.setColor(Color.red);
        g.drawOval(100,100,100,100);
        g.setColor(Color.green);
        g.fillRect(200,200,100,100);
        //养成习惯，画笔用完，还原到最初哟啊色
    }
}

鼠标监听事件、模拟画图工具

目的：想要实现鼠标绘画:

• 流程图

  

• 代码

  package com.jokerdig.lesson3;
  
  import java.awt.*;
  import java.awt.event.MouseAdapter;
  import java.awt.event.MouseEvent;
  import java.util.ArrayList;
  import java.util.Iterator;
  
  /**
   * @author Joker大雄
   * @data 2021/8/17 - 23:06
   **/
  public class TestMouseListener {
      public static void main(String[] args) {
          new MyFrame("画图");
      }
  
  }
  //自己的类
  class MyFrame extends Frame {
      //创建ArrayList
      ArrayList points;
      //绘画需要监听鼠标位置
  
      //构造器
      public MyFrame(String title) {
          super(title);
          setBounds(200,200,300,300);
  
          //用数组存放鼠标的点
         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){
          //画画需要监听鼠标,使用迭代器输出点Iterator
          Iterator iterator = points.iterator();
          while(iterator.hasNext()){
              Point point = (Point)iterator.next();
              g.setColor(Color.BLACK);
              g.fillOval(point.x,point.y,10,10);
          }
      }
  
      //添加一个点到界面
      public void addPoint(Point point){
          points.add(point);
      }
      
      //适配器模式
      private class MyMouseListener extends MouseAdapter{
          //鼠标 按下 弹起 按住不放
  
        //按压
          @Override
          public void mousePressed(MouseEvent e) {
             MyFrame frame=(MyFrame)e.getSource();
             //点击产生一个点,获取鼠标坐标画下点
              frame.addPoint(new Point(e.getX(),e.getY()));
  
              //每次点击重画一次
              frame.repaint();//刷新
          }
      }
  }

窗口监听事件

package com.jokerdig.lesson3;

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

/**
 * @author Joker大雄
 * @data 2021/8/17 - 23:28
 **/
public class TestWindow {
    public static void main(String[] args) {
        new windowFrame();
    }
}
class windowFrame extends Frame{

    public windowFrame(){
        setBackground(Color.BLUE);
        setBounds(100,100,200,200);
        setVisible(true);
       // addWindowListener(new MyWindowListener());
        //匿名内部类
        this.addWindowListener(new WindowAdapter() {



            @Override
            public void windowClosing(WindowEvent e) {
                System.out.println("windowClosing");
            }

            @Override
            public void windowActivated(WindowEvent e) {
                windowFrame f = (windowFrame) e.getSource();
                f.setTitle("被激活了");
                System.out.println("windowActivated");
            }
        });
    }
    //继承实现类，来避免实现接口重写太多方法
    class MyWindowListener extends WindowAdapter{

        @Override
        public void windowClosing(WindowEvent e) {
           //隐藏窗口
            setVisible(false);

            //关闭窗口
            System.exit(0);
        }
    }

}

键盘监听事件

package com.jokerdig.lesson3;

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

/**
 * @author Joker大雄
 * @data 2021/8/17 - 23:43
 **/
//键盘
public class TestKeyboardListener {
    public static void main(String[] args) {
        new keyFrame();
    }
}
class keyFrame extends Frame{
    public keyFrame(){
        setBounds(1,2,500,300);
        setVisible(true);

        this.addKeyListener(new KeyAdapter() {
          //键盘按压
            @Override
            public void keyPressed(KeyEvent e) {
                //获得键盘按下的键
                int keycode = e.getKeyCode();
                System.out.println(keycode);
                //不需要可以去记录，使用VK_XX
                if(keycode==KeyEvent.VK_UP){
                    System.out.println("你按下了上键");
                }
            }
        });
    }
}