GUI入门(2)

• • 鼠标监听
  • 窗口监听
  • 键盘监听

实现一个简单的模拟画图工具

package com.cupk.lesson03;

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


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);
        //存鼠标点击的点
        points = new ArrayList();

        //鼠标监听器，正对这个窗口
        this.addMouseListener(new MyMouseListener());
        setVisible(true);
    }

    @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
    public void addPaint(Point point){
        points.add(point);
    }

    public class MyMouseListener extends MouseAdapter {
        @Override
        public void mousePressed(MouseEvent e) {
            Myframe frame = (Myframe)e.getSource();
            frame.addPaint(new Point(e.getX(),e.getY()));

            frame.repaint();//刷新
        }
    }
}

package com.cupk.lesson03;


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


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);
        addWindowListener(new WindowAdapter() {

            //窗口关闭
            @Override
            public void windowClosing(WindowEvent e) {
                super.windowClosing(e);
            }
            //激活窗口
            @Override
            public void windowActivated(WindowEvent e) {
                super.windowActivated(e);
            }
        });
        setVisible(true);
    }

}

package com.cupk.lesson03;

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


public class TestKeyListener {
    public static void main(String[] args) {
        new Keyframe();
    }
}

class Keyframe extends frame {
    public Keyframe() {
        setBounds(1,2,300,400);
        setVisible(true);

        this.addKeyListener(new KeyAdapter() {
            @Override
            public void keyPressed(KeyEvent e) {
                //获取键盘下的键是哪个，当前的码
                if(e.getKeyCode() == KeyEvent.VK_UP){
                    System.out.println("你按下了上键");
                }
            }
        });
    }
}