实现鼠标画图的Java程序_CMS教程

import java awt Color;

import java awt Frame;

import java awt Graphics;

import java awt Point;

import java awt event MouseAdapter;

import java awt event MouseEvent;

import java awt event MouseListener;

import java util ArrayList;

import java util Iterator;

public class MyMouseAdapter {

public static void main(String[] args) {

new MyFrame ( drawing );

}

class MyFrame extends Frame{

ArrayList points=null;

MyFrame (String s){

super(s);

points=new ArrayList();

setLayout(null);

setBounds( );

this setBackground(new Color( ));

setVisible(true);

this addMouseListener(new Monitor ());

}

public void paint(Graphics g){

Iterator i=erator();

while(i hasNext()){

Point p=(Point)i next();

g setColor(Color blue);

g fillOval(p x p y );

}

public void addPoint(Point p){

points add(p);

}

class Monitor extends MouseAdapter{ //MouseAdapter实现了MouseListener接口

public void mousePressed(MouseEvent e){

MyFrame f=(MyFrame )e getSource();

f addPoint(new Point(e getX() e getY()));

f repaint(); //让Frame强制经行重画

}

lishixinzhi/Article/program/Java/hx/201311/26376

import javaapplet;

import javaawt;

import javaawtevent;

public class Tester extends Applet implements ActionListener

{

Button btn1,btn2,btn3,btn4;

public void init(){

setLayout(null);

btn1=new Button("绘制直线");

btn2=new Button("绘制矩形");

btn3=new Button("绘制圆");

add(btn1);

add(btn2);

add(btn3);

btn1setBounds(10, 60, 60, 20);

btn2setBounds(10, 90, 60, 20);

btn3setBounds(10, 120, 60, 20);

btn1addActionListener(this);

btn2addActionListener(this);

btn3addActionListener(this);

validate();

setVisible(true);

}

public void start(){

}

public void actionPerformed(ActionEvent e)

{

Graphics g=thisgetGraphics();

if(egetSource()==btn1)

{

gdrawLine(200, 100, 300, 200);

}

else if(egetSource()==btn2)

{

gdrawRect(200, 250, 200, 200);

}

else

{

gdrawArc(200, 500, 200, 200, 0, 360);

}

superpaint()的作用是把当前的区域清空，每次resize的时候就会自动调用paint()方法，paint()方法里先调用了superpaint()清空当前区域，再画一个矩型筐，当然每次只有一个了。另外你的算法也有漏洞，当你想从右上角拉到左下角画矩形的时候是没有反应的。下面这个程序修改了只画一个的错误，改进了右上角拉到左下角的漏洞，还增加了拖动的中间过程。没时间给你写注释，自己看吧。 import javaawt; import javaawtevent; import javautilVector; import javaxswing; public class Hello extends JFrame implements MouseListener,MouseMotionListener{ int x一,y一; Vector rectangles=null; public Hello(){ thissetTitle("画图小程序"); thisaddMouseListener(this); thisaddMouseMotionListener(this); thissetSize(四00,四00); rectangles=new Vector(); thissetVisible(true); thissetDefaultCloseOperation(JFrameEXIT_ON_CLOSE); } public void paint(Graphics g){ superpaint(g); gsetColor(ColorBLUE); for(int i=0;i<rectanglessize();i++){ Rectangle rec=rectanglesget(i); int tmp_x=recx; int tmp_y=recy; int tmp_w=recwidth; int tmp_h=recheight; gdrawRect(tmp_x,tmp_y,tmp_w,tmp_h); } } public static void main(String[] args) { new Hello(); } public void mouseClicked(MouseEvent e) { } public void mouseEntered(MouseEvent e) { } public void mouseExited(MouseEvent e) { } public void mousePressed(MouseEvent e) { x一=egetX();y一=egetY(); } public void mouseReleased(MouseEvent e) { int x二=egetX(); int y二=egetY(); int x=0; int y=0; Graphics g=thisgetGraphics(); gsetColor(ColorBLUE); int tmp_w=0; int tmp_h=0; if(x一x二){ x=x二; tmp_w=x一-x二; } if(y一y二){ y=y二; tmp_h=y一-y二; } rectanglesadd(new Rectangle(x,y,tmp_w,tmp_h)); thisrepaint(); } public void mouseDragged(MouseEvent e) { int x二=egetX(); int y二=egetY(); int x=0; int y=0; Graphics g=thisgetGraphics(); gsetColor(ColorBLUE); int tmp_w=0; int tmp_h=0; if(x一x二){ x=x二; tmp_w=x一-x二; } if(y一y二){ y=y二; tmp_h=y一-y二; } paint(g); gdrawRect(x,y,tmp_w,tmp_h); } public void mouseMoved(MouseEvent e) { }

楼主写一个html，很容易把下面代码嵌入到applet，可以google一下实现，

还有copy自己不知道算不算复制。。。-_-!

--------------------------------------------------------------------

楼主给你一个我的，直接保存成pbjava编译运行，就是你要的画图功能，可以参考一下

____________________________________________________________________

import javaapplet;

import javaawt;

import javaawtevent;

import javautil;

import javaxswing;

import javaawtgeom;

import javaio;

class Point implements Serializable

{

int x,y;

Color col;

int tool;

int boarder;

Point(int x, int y, Color col, int tool, int boarder)

{

thisx = x;

thisy = y;

thiscol = col;

thistool = tool;

thisboarder = boarder;

}

class paintboard extends Frame implements ActionListener,MouseMotionListener,MouseListener,ItemListener

{

int x = -1, y = -1;

int con = 1;//画笔大小

int Econ = 5;//橡皮大小

int toolFlag = 0;//toolFlag:工具标记

//toolFlag工具对应表：

//（0--画笔）；（1--橡皮）；（2--清除）；

//（3--直线）；（4--圆）；（5--矩形）；

Color c = new Color(0,0,0); //画笔颜色

BasicStroke size = new BasicStroke(con,BasicStrokeCAP_BUTT,BasicStrokeJOIN_BEVEL);//画笔粗细

Point cutflag = new Point(-1, -1, c, 6, con);//截断标志

Vector paintInfo = null;//点信息向量组

int n = 1;

FileInputStream picIn = null;

FileOutputStream picOut = null;

ObjectInputStream VIn = null;

ObjectOutputStream VOut = null;

// 工具面板--画笔，直线，圆，矩形，多边形,橡皮，清除/

Panel toolPanel;

Button eraser, drLine,drCircle,drRect;

Button clear ,pen;

Choice ColChoice,SizeChoice,EraserChoice;

Button colchooser;

Label 颜色,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();

/各工具按钮及选择项/

//颜色选择

ColChoice = new Choice();

ColChoiceadd("black");

ColChoiceadd("red");

ColChoiceadd("blue");

ColChoiceadd("green");

ColChoiceaddItemListener(this);

//画笔大小选择

SizeChoice = new Choice();

SizeChoiceadd("1");

SizeChoiceadd("3");

SizeChoiceadd("5");

SizeChoiceadd("7");

SizeChoiceadd("9");

SizeChoiceaddItemListener(this);

//橡皮大小选择

EraserChoice = new Choice();

EraserChoiceadd("5");

EraserChoiceadd("9");

EraserChoiceadd("13");

EraserChoiceadd("17");

EraserChoiceaddItemListener(this);

////////////////////////////////////////////////////

toolPanel = new Panel();

clear = new Button("清除");

eraser = new Button("橡皮");

pen = new Button("画笔");

drLine = new Button("画直线");

drCircle = new Button("画圆形");

drRect = new Button("画矩形");

openPic = new Button("打开图画");

savePic = new Button("保存图画");

colchooser = new Button("显示调色板");

//各组件事件监听

clearaddActionListener(this);

eraseraddActionListener(this);

penaddActionListener(this);

drLineaddActionListener(this);

drCircleaddActionListener(this);

drRectaddActionListener(this);

openPicaddActionListener(this);

savePicaddActionListener(this);

colchooseraddActionListener(this);

颜色 = new Label("画笔颜色",LabelCENTER);

大小B = new Label("画笔大小",LabelCENTER);

大小E = new Label("橡皮大小",LabelCENTER);

//面板添加组件

toolPaneladd(openPic);

toolPaneladd(savePic);

toolPaneladd(pen);

toolPaneladd(drLine);

toolPaneladd(drCircle);

toolPaneladd(drRect);

toolPaneladd(颜色); toolPaneladd(ColChoice);

toolPaneladd(大小B); toolPaneladd(SizeChoice);

toolPaneladd(colchooser);

toolPaneladd(eraser);

toolPaneladd(大小E); toolPaneladd(EraserChoice);

toolPaneladd(clear);

//工具面板到APPLET面板

add(toolPanel,BorderLayoutNORTH);

setBounds(60,60,900,600); setVisible(true);

validate();

//dialog for save and load

openPicture = new FileDialog(this,"打开图画",FileDialogLOAD);

openPicturesetVisible(false);

savePicture = new FileDialog(this,"保存图画",FileDialogSAVE);

savePicturesetVisible(false);

openPictureaddWindowListener(new WindowAdapter()

{

public void windowClosing(WindowEvent e)

{ openPicturesetVisible(false); }

});

savePictureaddWindowListener(new WindowAdapter()

{

public void windowClosing(WindowEvent e)

{ savePicturesetVisible(false); }

});

addWindowListener(new WindowAdapter()

{

public void windowClosing(WindowEvent e)

{ Systemexit(0);}

});

}

public void paint(Graphics g)

{

Graphics2D g2d = (Graphics2D)g;

Point p1,p2;

n = paintInfosize();

if(toolFlag==2)

gclearRect(0,0,getSize()width,getSize()height);//清除

for(int i=0; i<n ;i++){

p1 = (Point)paintInfoelementAt(i);

p2 = (Point)paintInfoelementAt(i+1);

size = new BasicStroke(p1boarder,BasicStrokeCAP_BUTT,BasicStrokeJOIN_BEVEL);

g2dsetColor(p1col);

g2dsetStroke(size);

if(p1tool==p2tool)

{

switch(p1tool)

{

case 0://画笔

Line2D line1 = new Line2DDouble(p1x, p1y, p2x, p2y);

g2ddraw(line1);

break;

case 1://橡皮

gclearRect(p1x, p1y, p1boarder, p1boarder);

break;

case 3://画直线

Line2D line2 = new Line2DDouble(p1x, p1y, p2x, p2y);

g2ddraw(line2);

break;

case 4://画圆

Ellipse2D ellipse = new Ellipse2DDouble(p1x, p1y, Mathabs(p2x-p1x) , Mathabs(p2y-p1y));

g2ddraw(ellipse);

break;

case 5://画矩形

Rectangle2D rect = new Rectangle2DDouble(p1x, p1y, Mathabs(p2x-p1x) , Mathabs(p2y-p1y));

g2ddraw(rect);

break;

case 6://截断，跳过

i=i+1;

break;

default :

}//end switch

}//end if

}//end for

}

public void itemStateChanged(ItemEvent e)

{

if(egetSource()==ColChoice)//预选颜色

{

String name = ColChoicegetSelectedItem();

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(egetSource()==SizeChoice)//画笔大小

{

String selected = SizeChoicegetSelectedItem();

if(selected=="1")

{

con = 1;