Java开发网 - 求助，帮忙改改这个程序啊

Topic: 求助，帮忙改改这个程序啊

1.求助，帮忙改改这个程序啊

Posted by: vickey312
Posted on: 2005-05-07 14:26

写出来一个程序是简单的画图，大侠们看了就知道了
但是有个小问题
怎么画后面的线的话，都会擦掉前面线的交点
恳求各位帮帮忙啊~~~
程序如下：
package c7.MouseDraw;
import java.awt.*;
import java.awt.event.*;

public class MouseDraw
{
public static void main(String[] args)
{
MouseFrame frame=new MouseFrame();
  frame.addWindowListener(new Wadapt());
  frame.setVisible(true);
}
}

class MouseFrame extends Frame
{
public MouseFrame()
{
setTitle("利用鼠标绘图");
  setSize(300,300);
  MousePanel panel=new MousePanel();
  add(panel);
}
}

class MousePanel extends Panel implements MouseListener,MouseMotionListener
{
private int x,y,start_X,start_Y,old_X,old_Y;
private boolean draw;
public MousePanel()
{
addMouseListener(this);
addMouseMotionListener(this);
}

public void mousePressed(MouseEvent evt)
{
start_X=evt.getX();
start_Y=evt.getY();
draw=false;
}
public void mouseReleased(MouseEvent evt){}

public void mouseClicked(MouseEvent evt){}

public void mouseEntered(MouseEvent evt)
{
setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
}

public void mouseExited(MouseEvent evt)
{
setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
}

public void mouseDragged(MouseEvent evt)
{
x=evt.getX();
y=evt.getY();
repaint();
}

public void mouseMoved(MouseEvent evt){}

public void update(Graphics g)
{
paint Present

;
}

public void paint(Graphics g)
{
if(!draw)
{
old_X=x;
old_Y=y;
draw=true;
}
else
{
g.setColor(getBackground());
g.drawLine(start_X,start_Y,old_X,old_Y);
old_X=x;
old_Y=y;
}
g.setColor(getForeground());
g.drawLine(start_X,start_Y,x,y);
}
}

class Wadapt extends WindowAdapter
{
public void windowClosing(WindowEvent evt)
{
Frame frm=(Frame)evt.getSource();
frm.setVisible(false);
frm.dispose();
System.exit(0);
}
}

2.Re:求助，帮忙改改这个程序啊 [Re: vickey312]	Copy to clipboard
Posted by: vickey312 Posted on: 2005-05-07 21:32 5555555555 没人帮我么？