GUI-画笔画点

GUI-画笔画点

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package com.zuoyan.lesson02;

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

/**
 * 鼠标监听器
 */
public class FirstMouseListener {
    
    
    public static void main(String[] args) {
    
    
        new MyMouseListener("画笔");
    }
}

class MyMouseListener extends Frame{
    
    
    //需要一个集合存储这些点
    ArrayList points;

    public MyMouseListener(String title) {
    
    
        super(title);
        setBounds(700, 300, 700, 400);

        points = new ArrayList();

		//添加鼠标监听器
        this.addMouseListener(new MyListener());

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

    @Override
    public void paint(Graphics g) {
    
    
        //画画监听事件，将点存储在集合中
        Iterator iterator = points.iterator();
        while (iterator.hasNext()) {
    
    
            Point point = (Point) iterator.next();
            g.setColor(Color.MAGENTA);
            g.fillOval(point.x, point.y, 10, 10);
        }
    }

    //将点添加到页面上
    public void addPoint(Point point) {
    
    
        points.add(point);
    }


    //适配器模式
    private class MyListener extends MouseAdapter {
    
    
        //按住鼠标时
        @Override
        public void mousePressed(MouseEvent e) {
    
    
            MyMouseListener myMouseListener = (MyMouseListener) e.getSource();

            myMouseListener.addPoint(new Point(e.getX(), e.getY()));

            //每次点击鼠标都需要重新画一遍
            myMouseListener.repaint();
        }
    }
}