java怎麼畫圖
『壹』 java 實現 簡單畫圖功能(簡單點的)
樓主給你一個我編的,直接保存成pb.java編譯運行,就是你要的畫圖功能
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import java.applet.*; 
import java.awt.*; 
import java.awt.event.*; 
import java.util.*; 
import javax.swing.*; 
import java.awt.geom.*; 
import java.io.*; 
class Point implements Serializable 
{ 
int x,y; 
Color col; 
int tool; 
int boarder; 
Point(int x, int y, Color col, int tool, int boarder) 
{ 
this.x = x; 
this.y = y; 
this.col = col; 
this.tool = tool; 
this.boarder = boarder; 
} 
} 
class paintboard extends Frame implements ActionListener,MouseMotionListener,MouseListener,ItemListener 
{ 
int x = -1, y = -1; 
int con = 1;//畫筆大小 
int Econ = 5;//橡皮大小 
int toolFlag = 0;//toolFlag:工具標記 
//toolFlag工具對應表: 
//(0--畫筆);(1--橡皮);(2--清除); 
//(3--直線);(4--圓);(5--矩形); 
Color c = new Color(0,0,0); //畫筆顏色 
BasicStroke size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL);//畫筆粗細 
Point cutflag = new Point(-1, -1, c, 6, con);//截斷標志 
Vector paintInfo = null;//點信息向量組 
int n = 1; 
FileInputStream picIn = null; 
FileOutputStream picOut = null; 
ObjectInputStream VIn = null; 
ObjectOutputStream VOut = null; 
// *工具面板--畫筆,直線,圓,矩形,多邊形,橡皮,清除*/ 
Panel toolPanel; 
Button eraser, drLine,drCircle,drRect; 
Button clear ,pen; 
Choice ColChoice,SizeChoice,EraserChoice; 
Button colchooser; 
Label 顏色,大小B,大小E; 
//保存功能 
Button openPic,savePic; 
FileDialog openPicture,savePicture; 
paintboard(String s) 
{ 
super(s); 
addMouseMotionListener(this); 
addMouseListener(this); 
paintInfo = new Vector(); 
/*各工具按鈕及選擇項*/ 
//顏色選擇 
ColChoice = new Choice(); 
ColChoice.add("black"); 
ColChoice.add("red"); 
ColChoice.add("blue"); 
ColChoice.add("green"); 
ColChoice.addItemListener(this); 
//畫筆大小選擇 
SizeChoice = new Choice(); 
SizeChoice.add("1"); 
SizeChoice.add("3"); 
SizeChoice.add("5"); 
SizeChoice.add("7"); 
SizeChoice.add("9"); 
SizeChoice.addItemListener(this); 
//橡皮大小選擇 
EraserChoice = new Choice(); 
EraserChoice.add("5"); 
EraserChoice.add("9"); 
EraserChoice.add("13"); 
EraserChoice.add("17"); 
EraserChoice.addItemListener(this); 
//////////////////////////////////////////////////// 
toolPanel = new Panel(); 
clear = new Button("清除"); 
eraser = new Button("橡皮"); 
pen = new Button("畫筆"); 
drLine = new Button("畫直線"); 
drCircle = new Button("畫圓形"); 
drRect = new Button("畫矩形"); 
openPic = new Button("打開圖畫"); 
savePic = new Button("保存圖畫"); 
colchooser = new Button("顯示調色板"); 
//各組件事件監聽 
clear.addActionListener(this); 
eraser.addActionListener(this); 
pen.addActionListener(this); 
drLine.addActionListener(this); 
drCircle.addActionListener(this); 
drRect.addActionListener(this); 
openPic.addActionListener(this); 
savePic.addActionListener(this); 
colchooser.addActionListener(this); 
顏色 = new Label("畫筆顏色",Label.CENTER); 
大小B = new Label("畫筆大小",Label.CENTER); 
大小E = new Label("橡皮大小",Label.CENTER); 
//面板添加組件 
toolPanel.add(openPic); 
toolPanel.add(savePic); 
toolPanel.add(pen); 
toolPanel.add(drLine); 
toolPanel.add(drCircle); 
toolPanel.add(drRect); 
toolPanel.add(顏色); toolPanel.add(ColChoice); 
toolPanel.add(大小B); toolPanel.add(SizeChoice); 
toolPanel.add(colchooser); 
toolPanel.add(eraser); 
toolPanel.add(大小E); toolPanel.add(EraserChoice); 
toolPanel.add(clear); 
//工具面板到APPLET面板 
add(toolPanel,BorderLayout.NORTH); 
setBounds(60,60,900,600); setVisible(true); 
validate(); 
//dialog for save and load 
openPicture = new FileDialog(this,"打開圖畫",FileDialog.LOAD); 
openPicture.setVisible(false); 
savePicture = new FileDialog(this,"保存圖畫",FileDialog.SAVE); 
savePicture.setVisible(false); 
openPicture.addWindowListener(new WindowAdapter() 
{ 
public void windowClosing(WindowEvent e) 
{ openPicture.setVisible(false); } 
}); 
savePicture.addWindowListener(new WindowAdapter() 
{ 
public void windowClosing(WindowEvent e) 
{ savePicture.setVisible(false); } 
}); 
addWindowListener(new WindowAdapter() 
{ 
public void windowClosing(WindowEvent e) 
{ System.exit(0);} 
}); 
} 
public void paint(Graphics g) 
{ 
Graphics2D g2d = (Graphics2D)g; 
Point p1,p2; 
n = paintInfo.size(); 
if(toolFlag==2) 
g.clearRect(0,0,getSize().width,getSize().height);//清除 
for(int i=0; i<n ;i++){ 
p1 = (Point)paintInfo.elementAt(i); 
p2 = (Point)paintInfo.elementAt(i+1); 
size = new BasicStroke(p1.boarder,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
g2d.setColor(p1.col); 
g2d.setStroke(size); 
if(p1.tool==p2.tool) 
{ 
switch(p1.tool) 
{ 
case 0://畫筆 
Line2D line1 = new Line2D.Double(p1.x, p1.y, p2.x, p2.y); 
g2d.draw(line1); 
break; 
case 1://橡皮 
g.clearRect(p1.x, p1.y, p1.boarder, p1.boarder); 
break; 
case 3://畫直線 
Line2D line2 = new Line2D.Double(p1.x, p1.y, p2.x, p2.y); 
g2d.draw(line2); 
break; 
case 4://畫圓 
Ellipse2D ellipse = new Ellipse2D.Double(p1.x, p1.y, Math.abs(p2.x-p1.x) , Math.abs(p2.y-p1.y)); 
g2d.draw(ellipse); 
break; 
case 5://畫矩形 
Rectangle2D rect = new Rectangle2D.Double(p1.x, p1.y, Math.abs(p2.x-p1.x) , Math.abs(p2.y-p1.y)); 
g2d.draw(rect); 
break; 
case 6://截斷,跳過 
i=i+1; 
break; 
default : 
}//end switch 
}//end if 
}//end for 
} 
public void itemStateChanged(ItemEvent e) 
{ 
if(e.getSource()==ColChoice)//預選顏色 
{ 
String name = ColChoice.getSelectedItem(); 
if(name=="black") 
{c = new Color(0,0,0); } 
else if(name=="red") 
{c = new Color(255,0,0);} 
else if(name=="green") 
{c = new Color(0,255,0);} 
else if(name=="blue") 
{c = new Color(0,0,255);} 
} 
else if(e.getSource()==SizeChoice)//畫筆大小 
{ 
String selected = SizeChoice.getSelectedItem(); 
if(selected=="1") 
{ 
con = 1; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="3") 
{ 
con = 3; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="5") 
{con = 5; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="7") 
{con = 7; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="9") 
{con = 9; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
} 
else if(e.getSource()==EraserChoice)//橡皮大小 
{ 
String Esize = EraserChoice.getSelectedItem(); 
if(Esize=="5") 
{ Econ = 5*2; } 
else if(Esize=="9") 
{ Econ = 9*2; } 
else if(Esize=="13") 
{ Econ = 13*2; } 
else if(Esize=="17") 
{ Econ = 17*3; } 
} 
} 
public void mouseDragged(MouseEvent e) 
{ 
Point p1 ; 
switch(toolFlag){ 
case 0://畫筆 
x = (int)e.getX(); 
y = (int)e.getY(); 
p1 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p1); 
repaint(); 
break; 
case 1://橡皮 
x = (int)e.getX(); 
y = (int)e.getY(); 
p1 = new Point(x, y, null, toolFlag, Econ); 
paintInfo.addElement(p1); 
repaint(); 
break; 
default : 
} 
} 
public void mouseMoved(MouseEvent e) {} 
public void update(Graphics g) 
{ 
paint(g); 
} 
public void mousePressed(MouseEvent e) 
{ 
Point p2; 
switch(toolFlag){ 
case 3://直線 
x = (int)e.getX(); 
y = (int)e.getY(); 
p2 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p2); 
break; 
case 4: //圓 
x = (int)e.getX(); 
y = (int)e.getY(); 
p2 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p2); 
break; 
case 5: //矩形 
x = (int)e.getX(); 
y = (int)e.getY(); 
p2 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p2); 
break; 
default : 
} 
} 
public void mouseReleased(MouseEvent e) 
{ 
Point p3; 
switch(toolFlag){ 
case 0://畫筆 
paintInfo.addElement(cutflag); 
break; 
case 1: //eraser 
paintInfo.addElement(cutflag); 
break; 
case 3://直線 
x = (int)e.getX(); 
y = (int)e.getY(); 
p3 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p3); 
paintInfo.addElement(cutflag); 
repaint(); 
break; 
case 4: //圓 
x = (int)e.getX(); 
y = (int)e.getY(); 
p3 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p3); 
paintInfo.addElement(cutflag); 
repaint(); 
break; 
case 5: //矩形 
x = (int)e.getX(); 
y = (int)e.getY(); 
p3 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p3); 
paintInfo.addElement(cutflag); 
repaint(); 
break; 
default: 
} 
} 
public void mouseEntered(MouseEvent e){} 
public void mouseExited(MouseEvent e){} 
public void mouseClicked(MouseEvent e){} 
public void actionPerformed(ActionEvent e) 
{ 
if(e.getSource()==pen)//畫筆 
{toolFlag = 0;} 
if(e.getSource()==eraser)//橡皮 
{toolFlag = 1;} 
if(e.getSource()==clear)//清除 
{ 
toolFlag = 2; 
paintInfo.removeAllElements(); 
repaint(); 
} 
if(e.getSource()==drLine)//畫線 
{toolFlag = 3;} 
if(e.getSource()==drCircle)//畫圓 
{toolFlag = 4;} 
if(e.getSource()==drRect)//畫矩形 
{toolFlag = 5;} 
if(e.getSource()==colchooser)//調色板 
{ 
Color newColor = JColorChooser.showDialog(this,"調色板",c); 
c = newColor; 
} 
if(e.getSource()==openPic)//打開圖畫 
{ 
openPicture.setVisible(true); 
if(openPicture.getFile()!=null) 
{ 
int tempflag; 
tempflag = toolFlag; 
toolFlag = 2 ; 
repaint(); 
try{ 
paintInfo.removeAllElements(); 
File filein = new File(openPicture.getDirectory(),openPicture.getFile()); 
picIn = new FileInputStream(filein); 
VIn = new ObjectInputStream(picIn); 
paintInfo = (Vector)VIn.readObject(); 
VIn.close(); 
repaint(); 
toolFlag = tempflag; 
} 
catch(ClassNotFoundException IOe2) 
{ 
repaint(); 
toolFlag = tempflag; 
System.out.println("can not read object"); 
} 
catch(IOException IOe) 
{ 
repaint(); 
toolFlag = tempflag; 
System.out.println("can not read file"); 
} 
} 
} 
if(e.getSource()==savePic)//保存圖畫 
{ 
savePicture.setVisible(true); 
try{ 
File fileout = new File(savePicture.getDirectory(),savePicture.getFile()); 
picOut = new FileOutputStream(fileout); 
VOut = new ObjectOutputStream(picOut); 
VOut.writeObject(paintInfo); 
VOut.close(); 
} 
catch(IOException IOe) 
{ 
System.out.println("can not write object"); 
} 
} 
} 
}//end paintboard 
public class pb 
{ 
public static void main(String args[]) 
{ new paintboard("畫圖程序"); } 
}
『貳』 用Java一個簡單的畫圖程序
簡單啊,先引入相應的組件包import java.awt.*;import java.awt.event.*;import javax.swing.*;寫的類要繼承JFrame 接下來就是調用剛剛引入包裡面的方法了,paint();這是就思路了。
『叄』 java web中,如何在頁面上畫圖。
頁面畫圖用java 2d的api即可。例子網上很多。
『肆』 誰有簡單的JAVA畫圖程序
////保存一個pb.java文件直接編譯執行
import java.applet.*; 
import java.awt.*; 
import java.awt.event.*; 
import java.util.*; 
import javax.swing.*; 
import java.awt.geom.*; 
import java.io.*; 
class Point implements Serializable 
{ 
int x,y; 
Color col; 
int tool; 
int boarder; 
Point(int x, int y, Color col, int tool, int boarder) 
{ 
this.x = x; 
this.y = y; 
this.col = col; 
this.tool = tool; 
this.boarder = boarder; 
} 
} 
class paintboard extends Frame implements ActionListener,MouseMotionListener,MouseListener,ItemListener 
{ 
int x = -1, y = -1; 
int con = 1;//畫筆大小 
int Econ = 5;//橡皮大小 
int toolFlag = 0;//toolFlag:工具標記 
//toolFlag工具對應表: 
//(0--畫筆);(1--橡皮);(2--清除); 
//(3--直線);(4--圓);(5--矩形); 
Color c = new Color(0,0,0); //畫筆顏色 
BasicStroke size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL);//畫筆粗細 
Point cutflag = new Point(-1, -1, c, 6, con);//截斷標志 
Vector paintInfo = null;//點信息向量組 
int n = 1; 
FileInputStream picIn = null; 
FileOutputStream picOut = null; 
ObjectInputStream VIn = null; 
ObjectOutputStream VOut = null; 
// *工具面板--畫筆,直線,圓,矩形,多邊形,橡皮,清除*/ 
Panel toolPanel; 
Button eraser, drLine,drCircle,drRect; 
Button clear ,pen; 
Choice ColChoice,SizeChoice,EraserChoice; 
Button colchooser; 
Label 顏色,大小B,大小E; 
//保存功能 
Button openPic,savePic; 
FileDialog openPicture,savePicture; 
paintboard(String s) 
{ 
super(s); 
addMouseMotionListener(this); 
addMouseListener(this); 
paintInfo = new Vector(); 
/*各工具按鈕及選擇項*/ 
//顏色選擇 
ColChoice = new Choice(); 
ColChoice.add("black"); 
ColChoice.add("red"); 
ColChoice.add("blue"); 
ColChoice.add("green"); 
ColChoice.addItemListener(this); 
//畫筆大小選擇 
SizeChoice = new Choice(); 
SizeChoice.add("1"); 
SizeChoice.add("3"); 
SizeChoice.add("5"); 
SizeChoice.add("7"); 
SizeChoice.add("9"); 
SizeChoice.addItemListener(this); 
//橡皮大小選擇 
EraserChoice = new Choice(); 
EraserChoice.add("5"); 
EraserChoice.add("9"); 
EraserChoice.add("13"); 
EraserChoice.add("17"); 
EraserChoice.addItemListener(this); 
//////////////////////////////////////////////////// 
toolPanel = new Panel(); 
clear = new Button("清除"); 
eraser = new Button("橡皮"); 
pen = new Button("畫筆"); 
drLine = new Button("畫直線"); 
drCircle = new Button("畫圓形"); 
drRect = new Button("畫矩形"); 
openPic = new Button("打開圖畫"); 
savePic = new Button("保存圖畫"); 
colchooser = new Button("顯示調色板"); 
//各組件事件監聽 
clear.addActionListener(this); 
eraser.addActionListener(this); 
pen.addActionListener(this); 
drLine.addActionListener(this); 
drCircle.addActionListener(this); 
drRect.addActionListener(this); 
openPic.addActionListener(this); 
savePic.addActionListener(this); 
colchooser.addActionListener(this); 
顏色 = new Label("畫筆顏色",Label.CENTER); 
大小B = new Label("畫筆大小",Label.CENTER); 
大小E = new Label("橡皮大小",Label.CENTER); 
//面板添加組件 
toolPanel.add(openPic); 
toolPanel.add(savePic); 
toolPanel.add(pen); 
toolPanel.add(drLine); 
toolPanel.add(drCircle); 
toolPanel.add(drRect); 
toolPanel.add(顏色); toolPanel.add(ColChoice); 
toolPanel.add(大小B); toolPanel.add(SizeChoice); 
toolPanel.add(colchooser); 
toolPanel.add(eraser); 
toolPanel.add(大小E); toolPanel.add(EraserChoice); 
toolPanel.add(clear); 
//工具面板到APPLET面板 
add(toolPanel,BorderLayout.NORTH); 
setBounds(60,60,900,600); setVisible(true); 
validate(); 
//dialog for save and load 
openPicture = new FileDialog(this,"打開圖畫",FileDialog.LOAD); 
openPicture.setVisible(false); 
savePicture = new FileDialog(this,"保存圖畫",FileDialog.SAVE); 
savePicture.setVisible(false); 
openPicture.addWindowListener(new WindowAdapter() 
{ 
public void windowClosing(WindowEvent e) 
{ openPicture.setVisible(false); } 
}); 
savePicture.addWindowListener(new WindowAdapter() 
{ 
public void windowClosing(WindowEvent e) 
{ savePicture.setVisible(false); } 
}); 
addWindowListener(new WindowAdapter() 
{ 
public void windowClosing(WindowEvent e) 
{ System.exit(0);} 
}); 
} 
public void paint(Graphics g) 
{ 
Graphics2D g2d = (Graphics2D)g; 
Point p1,p2; 
n = paintInfo.size(); 
if(toolFlag==2) 
g.clearRect(0,0,getSize().width,getSize().height);//清除 
for(int i=0; i<n ;i++){ 
p1 = (Point)paintInfo.elementAt(i); 
p2 = (Point)paintInfo.elementAt(i+1); 
size = new BasicStroke(p1.boarder,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
g2d.setColor(p1.col); 
g2d.setStroke(size); 
if(p1.tool==p2.tool) 
{ 
switch(p1.tool) 
{ 
case 0://畫筆 
Line2D line1 = new Line2D.Double(p1.x, p1.y, p2.x, p2.y); 
g2d.draw(line1); 
break; 
case 1://橡皮 
g.clearRect(p1.x, p1.y, p1.boarder, p1.boarder); 
break; 
case 3://畫直線 
Line2D line2 = new Line2D.Double(p1.x, p1.y, p2.x, p2.y); 
g2d.draw(line2); 
break; 
case 4://畫圓 
Ellipse2D ellipse = new Ellipse2D.Double(p1.x, p1.y, Math.abs(p2.x-p1.x) , Math.abs(p2.y-p1.y)); 
g2d.draw(ellipse); 
break; 
case 5://畫矩形 
Rectangle2D rect = new Rectangle2D.Double(p1.x, p1.y, Math.abs(p2.x-p1.x) , Math.abs(p2.y-p1.y)); 
g2d.draw(rect); 
break; 
case 6://截斷,跳過 
i=i+1; 
break; 
default : 
}//end switch 
}//end if 
}//end for 
} 
public void itemStateChanged(ItemEvent e) 
{ 
if(e.getSource()==ColChoice)//預選顏色 
{ 
String name = ColChoice.getSelectedItem(); 
if(name=="black") 
{c = new Color(0,0,0); } 
else if(name=="red") 
{c = new Color(255,0,0);} 
else if(name=="green") 
{c = new Color(0,255,0);} 
else if(name=="blue") 
{c = new Color(0,0,255);} 
} 
else if(e.getSource()==SizeChoice)//畫筆大小 
{ 
String selected = SizeChoice.getSelectedItem(); 
if(selected=="1") 
{ 
con = 1; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="3") 
{ 
con = 3; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="5") 
{con = 5; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="7") 
{con = 7; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
else if(selected=="9") 
{con = 9; 
size = new BasicStroke(con,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL); 
} 
} 
else if(e.getSource()==EraserChoice)//橡皮大小 
{ 
String Esize = EraserChoice.getSelectedItem(); 
if(Esize=="5") 
{ Econ = 5*2; } 
else if(Esize=="9") 
{ Econ = 9*2; } 
else if(Esize=="13") 
{ Econ = 13*2; } 
else if(Esize=="17") 
{ Econ = 17*3; } 
} 
} 
public void mouseDragged(MouseEvent e) 
{ 
Point p1 ; 
switch(toolFlag){ 
case 0://畫筆 
x = (int)e.getX(); 
y = (int)e.getY(); 
p1 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p1); 
repaint(); 
break; 
case 1://橡皮 
x = (int)e.getX(); 
y = (int)e.getY(); 
p1 = new Point(x, y, null, toolFlag, Econ); 
paintInfo.addElement(p1); 
repaint(); 
break; 
default : 
} 
} 
public void mouseMoved(MouseEvent e) {} 
public void update(Graphics g) 
{ 
paint(g); 
} 
public void mousePressed(MouseEvent e) 
{ 
Point p2; 
switch(toolFlag){ 
case 3://直線 
x = (int)e.getX(); 
y = (int)e.getY(); 
p2 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p2); 
break; 
case 4: //圓 
x = (int)e.getX(); 
y = (int)e.getY(); 
p2 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p2); 
break; 
case 5: //矩形 
x = (int)e.getX(); 
y = (int)e.getY(); 
p2 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p2); 
break; 
default : 
} 
} 
public void mouseReleased(MouseEvent e) 
{ 
Point p3; 
switch(toolFlag){ 
case 0://畫筆 
paintInfo.addElement(cutflag); 
break; 
case 1: //eraser 
paintInfo.addElement(cutflag); 
break; 
case 3://直線 
x = (int)e.getX(); 
y = (int)e.getY(); 
p3 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p3); 
paintInfo.addElement(cutflag); 
repaint(); 
break; 
case 4: //圓 
x = (int)e.getX(); 
y = (int)e.getY(); 
p3 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p3); 
paintInfo.addElement(cutflag); 
repaint(); 
break; 
case 5: //矩形 
x = (int)e.getX(); 
y = (int)e.getY(); 
p3 = new Point(x, y, c, toolFlag, con); 
paintInfo.addElement(p3); 
paintInfo.addElement(cutflag); 
repaint(); 
break; 
default: 
} 
} 
public void mouseEntered(MouseEvent e){} 
public void mouseExited(MouseEvent e){} 
public void mouseClicked(MouseEvent e){} 
public void actionPerformed(ActionEvent e) 
{ 
if(e.getSource()==pen)//畫筆 
{toolFlag = 0;} 
if(e.getSource()==eraser)//橡皮 
{toolFlag = 1;} 
if(e.getSource()==clear)//清除 
{ 
toolFlag = 2; 
paintInfo.removeAllElements(); 
repaint(); 
} 
if(e.getSource()==drLine)//畫線 
{toolFlag = 3;} 
if(e.getSource()==drCircle)//畫圓 
{toolFlag = 4;} 
if(e.getSource()==drRect)//畫矩形 
{toolFlag = 5;} 
if(e.getSource()==colchooser)//調色板 
{ 
Color newColor = JColorChooser.showDialog(this,"調色板",c); 
c = newColor; 
} 
if(e.getSource()==openPic)//打開圖畫 
{ 
openPicture.setVisible(true); 
if(openPicture.getFile()!=null) 
{ 
int tempflag; 
tempflag = toolFlag; 
toolFlag = 2 ; 
repaint(); 
try{ 
paintInfo.removeAllElements(); 
File filein = new File(openPicture.getDirectory(),openPicture.getFile()); 
picIn = new FileInputStream(filein); 
VIn = new ObjectInputStream(picIn); 
paintInfo = (Vector)VIn.readObject(); 
VIn.close(); 
repaint(); 
toolFlag = tempflag; 
} 
catch(ClassNotFoundException IOe2) 
{ 
repaint(); 
toolFlag = tempflag; 
System.out.println("can not read object"); 
} 
catch(IOException IOe) 
{ 
repaint(); 
toolFlag = tempflag; 
System.out.println("can not read file"); 
} 
} 
} 
if(e.getSource()==savePic)//保存圖畫 
{ 
savePicture.setVisible(true); 
try{ 
File fileout = new File(savePicture.getDirectory(),savePicture.getFile()); 
picOut = new FileOutputStream(fileout); 
VOut = new ObjectOutputStream(picOut); 
VOut.writeObject(paintInfo); 
VOut.close(); 
} 
catch(IOException IOe) 
{ 
System.out.println("can not write object"); 
} 
} 
} 
}//end paintboard 
public class pb 
{ 
public static void main(String args[]) 
{ new paintboard("畫圖程序"); } 
}
『伍』 用java編寫一個簡單的畫圖程序。不用復雜
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import javax.swing.*;
//不規則圖形的繪制
public class IrregularShapeDemo extends JFrame {
	
	GeneralPath gPath= new GeneralPath(); //GeneralPath對象實例
	Point aPoint; 
	
    //構造函數
    public IrregularShapeDemo() {
		super("不規則圖形的繪制"); //調用父類構造函數
		enableEvents(AWTEvent.MOUSE_EVENT_MASK|AWTEvent.MOUSE_MOTION_EVENT_MASK); //允許事件
		
		setSize(300, 200); //設置窗口尺寸
		setVisible(true); //設置窗口可視
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); //關閉窗口時退出程序
	}
	public void paint(Graphics g) { //重載窗口組件的paint()方法
		Graphics2D g2D = (Graphics2D)g;	//獲取圖形環境
		g2D.draw(gPath); //繪制路徑
	}
	public static void main(String[] args) {
		new IrregularShapeDemo();
	}
	
	protected void processMouseEvent(MouseEvent e) { //滑鼠事件處理
		if(e.getID() == MouseEvent.MOUSE_PRESSED) {
			aPoint = e.getPoint(); //得到當前滑鼠點
			gPath = new GeneralPath(); //重新實例化GeneralPath對象
			gPath.moveTo(aPoint.x,aPoint.y); //設置路徑點
		}
	}
		
	protected void processMouseMotionEvent(MouseEvent e) { //滑鼠運動事件處理
		if(e.getID() == MouseEvent.MOUSE_DRAGGED) {
			aPoint = e.getPoint(); //得到當前滑鼠點
			gPath.lineTo(aPoint.x, aPoint.y); //設置路徑
			gPath.moveTo(aPoint.x, aPoint.y);
			repaint(); //重繪組件
		}
	}	
}
