www.gusucode.com > Java 编写画图工具源代码 > Java 编写画图工具源代码\www.gusucode.com\步骤1.txt

    //实现了主要的框架和画图的功能

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


public class MyPaint extends JFrame {
	
	class DrawingPanel extends JPanel{
		//构造DrawingPanel实例
		public DrawingPanel(){
			setBackground(Color.white);
			addMouseListener(new MyMouseListener());
			addMouseMotionListener(new MyMouseListener());
			
		}
	
		
		public void paint(Graphics g){
			g.setColor(color);
			g.drawLine(oldX, oldY, newX, newY);
			
		}
		class MyMouseListener extends MouseAdapter implements MouseMotionListener{
			//单击响应记录座标
			public void mousePressed(MouseEvent e){
				oldX = newX = e.getX();
				oldY = newY = e.getY();
			}
			//拖动响应画出线条
			public void mouseDragged(MouseEvent e){
				oldX = newX;
				oldY = newY;
				newX = e.getX();
				newY = e.getY();
				repaint();
				
			}
		}
		
		
		
	}
	public MyPaint(String title){
		super(title);
	}
	
	//内容面板
	Container container = getContentPane();
	//座标的记录
	int oldX, oldY, newX, newY;
	//画图面板
	DrawingPanel panel = new DrawingPanel();
	//画笔颜色
	Color color = Color.blue;
	
	//生成JFrame
	public void go(){
		setSize(500, 500);
		setLocation(200, 200);
		container.add(panel);
		setVisible(true);
		addWindowListener(
				new WindowAdapter(){
					public void windowClosing(WindowEvent e){
						System.exit(0);
					}
				});
	}
	public static void main(String[] args) {
		
		//设定系统外观为默认外观
		try{
			UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
		}
		catch (Exception e){
			System.out.print(e);
		}
		
		//生成主要的框架
		MyPaint paint = new MyPaint("java实验 绘图工具 V2.0");
		paint.go();
		

	}

}