newdraw.java

一个简单的画图程序

//MouseDraw

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

public class Newdraw
{
	public static void main(String[] args)
	{
		MouseFrame frame = new MouseFrame();
		frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
		frame.show();
	}
}

class MouseFrame extends JFrame implements ActionListener
{
	public JMenuItem save;
	public JMenuItem open;
	public JMenuItem close;
	MousePanel panel;
	int n;
	public MouseFrame()
	{
		setTitle("利用鼠标画图");
		setSize(WIDTH, HEIGHT);
		
		JMenuBar menuBar=new JMenuBar();
		setJMenuBar(menuBar);
		JMenu fileMenu=new JMenu("File");
		save=new JMenuItem("Save");
		save.addActionListener(this);
		fileMenu.add(save);
		
		open=new JMenuItem("open");
	    open.addActionListener(this);
		fileMenu.add(open);
	  menuBar.add(fileMenu);
	
		// 将panel加入到frame		
		panel = new MousePanel();
		Container contentPane = getContentPane();
		contentPane.add(panel);
		
	}

		public void actionPerformed(ActionEvent e)
		{
			if(e.getSource()==save)
	       {
	       	    n=0;
	    	    FileDialog filedialog_save=new FileDialog(this,"save",FileDialog.SAVE);
	    	    filedialog_save.setVisible(true);
	    	    try{
	    	    	File file=new File(filedialog_save.getDirectory(),filedialog_save.getFile());
	    	    	FileWriter tofile=new FileWriter(file);
	    	    	BufferedWriter out=new BufferedWriter(tofile);
	    	    	for(int i=0;i<panel.list.size();i++)
	    	    	{
	    	    		MyShape ms=(MyShape)(panel.list.get(i));
	    	    		String ws=ms.getX()+" "+ms.getY()+" "+ms.getW()+" "+ms.getH()+" "+ms.getShape()+" ";
	    	    		out.write(ws,0,ws.length());
	    	    		out.flush();
	    	    		n++;
	    	    	}
	    	    }
	    	    catch(FileNotFoundException e1){}
	    	    catch(IOException e2){}
	    
	        }
	        else if(e.getSource()==open)
	        {
	        	int i=0;
	        	panel.list.clear();
	        	FileDialog filedialog_open=new FileDialog(this,"open",FileDialog.LOAD);
	    	    filedialog_open.setVisible(true);
	    	    try
	    	    {
	    	    File file=new File(filedialog_open.getDirectory(),filedialog_open.getFile());
	    	    FileReader file_reader=new FileReader(file);
	    	    BufferedReader in=new  BufferedReader(file_reader);
	    	    String rs;
	    	    rs=in.readLine();
 
	    	    	int rect[]=new int[5];
	    	    	int count=-1;
	    	    	Color c;
	    	    
	    	    	StringTokenizer st=new StringTokenizer(rs," ");
	    	    	while(st.hasMoreTokens())
	    	    	{
	    	    		String ms=st.nextToken();
	    	    		count=++count%5;
	    	    		rect[count]=Integer.parseInt(ms);
	    	    	    if(count==4&&rect[4]!=0) 
	    	    	    {
	    	    	    	panel.currentS=new MyShape(0,0,0,0,Color.black,0);
	    	    	    	switch(rect[4])
	    	    		    {
	    	    		
	    	    		     case 1:
				             	{
				             		MyArc a=new MyArc(rect[0],rect[1],rect[2],rect[3],Color.red,rect[4]);
	    	    		            panel.list.add(a);
	    	    		        }
	    	    		      break; 
	    	    		       case 2:
				             	{
				             		MyRect r=new MyRect(rect[0],rect[1],rect[2],rect[3],Color.red,rect[4]);
	    	    		            panel.list.add(r);
	    	    		        }
	    	    		      break;
	    	    		      case 3:
				             	{
				             		MyLine r=new MyLine(rect[0],rect[1],rect[2],rect[3],Color.red,rect[4]);
	    	    		            panel.list.add(r);
	    	    		        }
	    	    		      break;
	    	    		     }
	    	    	    }
	    	    	    
	    	    	}
	    	    panel.repaint();
	    	 }
	    	    catch(FileNotFoundException e1){}
	    	    catch(IOException e2){}
	        }
		}

	public static final int WIDTH = 500;
	public static final int HEIGHT = 600;  	
}

class MousePanel extends JPanel implements ActionListener
{

	public int shapetype=1;  //当前所画图形类型
	private int mouseFromx=0,mouseFromy=0,mouseEndx=0,mouseEndy=0;//鼠标的位置
	private JButton bt1,bt2,bt3,bt4,bt5,bt6;//按钮
	public ArrayList list;  //所有 图形所在数组
	public MyShape currentS;
	private boolean mousePressed=false;  //鼠标是否按下
	private Color c;
	
	public MousePanel()
	{
		c=new Color(0,0,0);
		currentS=new MyShape(0,0,0,0,c,0);
		
		bt1=new JButton("圆");
		bt2=new JButton("矩形");
		bt3=new JButton("直线");
		bt4=new JButton("清空");
		bt5=new JButton("红色");
		bt6=new JButton("蓝色");
		
		list=new ArrayList();
	   
		add(bt1);
		add(bt2);
		add(bt3);
		add(bt4);
		add(bt5);
		add(bt6);
		
		bt1.addActionListener(this);
		bt3.addActionListener(this);
		bt2.addActionListener(this);
		bt4.addActionListener(this);
        bt5.addActionListener(this);
		bt6.addActionListener(this);

	
		//注册监听器
		addMouseListener(new MouseHandler());
		addMouseMotionListener(new MouseMotionHandler());
	}
	
	public void paintComponent(Graphics g)
	{
		super.paintComponent(g);
		int i;
		MyShape s=new MyShape(0,0,0,0,c,0);
		if(mousePressed==true)
		{
	
		     currentS.drawShape(g);
		   //画此前所有的图形.
			for( i=0;i<list.size();i++)
		   {
		   	   s=(MyShape)list.get(i);
               s.drawShape(g);
               
		    }
		 }

	}

	public void actionPerformed(ActionEvent event)
	{
		Object source=event.getSource();
		
		if(source==bt1)
		    shapetype=1;
		else if(source==bt2)
		  shapetype=2;
	    else if(source==bt3)
	       shapetype=3;
		 else if(source==bt4)
		 {
		     	list.clear();
		     	c=new Color(0,0,0);
		     	currentS=new MyShape(0,0,0,0,c,0);
		     	repaint();
		 }
		if(source==bt5)
		{
			c=new Color(255,0,0);
		}
		else if(source==bt6)
		{
			c=new Color(0,0,255);
		}
		

	}
	
	
	private class MouseHandler extends MouseAdapter
	{
		public void mousePressed(MouseEvent event)
		{
			//得到鼠标光标的当前位置
			mouseFromx = event.getX();
			mouseFromy = event.getY();
		    mousePressed=true;
		}
		public void mouseReleased(MouseEvent event)
		{
			
			mouseEndx=event.getX();
			mouseEndy=event.getY();
			
			//鼠标松开后，将此前正在画的矩形current放入list，形状放入shape
			int w=mouseEndx-mouseFromx;
			int h=mouseEndy-mouseFromy;
			switch(shapetype)
			{
				case 1:
				{
					MyArc a=new MyArc(mouseFromx,mouseFromy,w,h,c,1);
					list.add(a);
				}
				break;
				case 2:
				{
					MyRect r=new MyRect(mouseFromx,mouseFromy,w,h,c,2);
					list.add(r);
				}
				break;
				case 3:
				{
					MyLine l=new MyLine(mouseFromx,mouseFromy,w,h,c,3);
					list.add(l);
				}
				break;
			}			
            
			repaint();
		
		}
	}
	
	private class MouseMotionHandler
		implements MouseMotionListener
	{
		public void mouseMoved(MouseEvent event)
		{

		}
		public void mouseDragged(MouseEvent event)
		{
			mouseEndx = event.getX();
			mouseEndy = event.getY();
			//得到鼠标移动过程中的当前图形
				switch(shapetype)
			{
				case 1:
				{
					MyArc a=new MyArc(mouseFromx,mouseFromy,mouseEndx-mouseFromx,mouseEndy-mouseFromy,c,1);
					currentS=a;
				}
				break;
				case 2:
				{
					MyRect r=new MyRect(mouseFromx,mouseFromy,mouseEndx-mouseFromx,mouseEndy-mouseFromy,c,2);
					currentS=r;
				}
				break;
				case 3:
				{
					MyLine l=new MyLine(mouseFromx,mouseFromy,mouseEndx-mouseFromx,mouseEndy-mouseFromy,c,3);
					currentS=l;
				}
				break;
			}	
		    repaint();
		}
	}
}
class MyShape 
{
   protected int x,y,w,h,s;
   Color color;
   public MyShape(int x1,int y1,int w1,int h1,Color c1,int s1)
   {
   	  x=x1;
   	  y=y1;
   	  w=w1;
   	  h=h1;
   	  s=s1;
   	  color=c1;
   }
	public void drawShape(Graphics g)
	{
		g.setColor(color);
	}
	public String getX()
	{
		return x+"";
	}
	public String getY()
	{
		return y+"";
	}
		public String getW()
	{
		return w+"";
	}
		public String getH()
	{
		return h+"";
	}
	public Color getColor()
	{
		return color;
	}
	public int getShape()
	{
		return s;
	}
}
class MyLine extends MyShape
{
	public MyLine(int x1,int y1,int w1,int h1,Color c1,int s1)
	{
		super(x1,y1,w1,h1,c1,s1);
	}
	public void drawShape(Graphics g)
	{
		super.drawShape(g);
		g.drawLine(x,y,x+w,y+h);
	}

}
class MyArc extends MyShape
{
	public MyArc(int x1,int y1,int w1,int h1,Color c1,int s1)
	{
		super(x1,y1,w1,h1,c1,s1);
	}
	public void drawShape(Graphics g)
	{
		super.drawShape(g);
		if(w>0&&h>0)
		     g.drawArc(x,y,w,h,0,360);
        if(w<0&&h>0)
		     g.drawArc(x+w,y,Math.abs(w),h,0,360);
		if(w<0&&h<0)
		    g.drawArc(x+w,y+h,Math.abs(w),Math.abs(h),0,360);
		if(w>0&&h<0)
		     g.drawArc(x,y+h,Math.abs(w),Math.abs(h),0,360);
	}

}
class MyRect extends MyShape
{
	public MyRect(int x1,int y1,int w1,int h1,Color c1,int s1)
	{
		super(x1,y1,w1,h1,c1,s1);
	}
	public void drawShape(Graphics g)
	{
		super.drawShape(g);
		if(w>0&&h>0)
		     g.drawRect(x,y,w,h);
		if(w<0&&h>0)
		     g.drawRect(x+w,y,Math.abs(w),h);
         if(w<0&&h<0)
		      g.drawRect(x+w,y+h,Math.abs(w),Math.abs(h));
		 if(w>0&&h<0)
		    g.drawRect(x,y+h,Math.abs(w),Math.abs(h));
	}

}