Question

java画图板用什么模式实现易于维护

Answer 1

package draw;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.io.*;
import java.util.*;
import javax.swing.*;

//the point
//impress the info of one point,the x and y

class OnePoint implements Serializable
{
int x;
int y;
int tool;
Color c;
int border;
public OnePoint(int x,int y,int tool,Color cc,int border)
{
this.x=x;
this.y=y;
this.tool=tool;
this.c=cc;
this.border=border;
}
public static void main(String[] args)
{
DrawingBoard oneBorder=new DrawingBoard();
}
}

class DrawingBoard extends Frame implements MouseListener,ItemListener,ActionListener,MouseMotionListener
{
Button pen,line,ellipse,rect,clear,colorboard,storebutton,openbutton;
Choice sizechoice,colorchoice ;
Label pensize, pencolor;
Panel panel ;
FileDialog storefile, openfile;
FileInputStream filein;
FileOutputStream fileout;
ObjectInputStream objectin;
ObjectOutputStream objectout;

int mode=0;
int flagtool=0;
Color flagcolor;
int border;
BasicStroke size;
private Point2D[] p=new Point2D[3];;

OnePoint p1,p2;
Vector<OnePoint> points=new Vector<OnePoint>();
public DrawingBoard()
{
pen=new Button("画笔");
line=new Button("直线");
ellipse=new Button("圆");
rect=new Button("矩形");
clear=new Button("清除");
colorboard=new Button("调色板");
storebutton=new Button("存储文件");
openbutton=new Button("打开文件");

pensize=new Label("画笔大小");
pencolor=new Label("画笔颜色");

storefile=new FileDialog(this,"存储文件",FileDialog.SAVE);
storefile.setVisible(false);
storefile.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
storefile.setVisible(false);
}
});
openfile=new FileDialog(this,"打开文件",FileDialog.LOAD);
openfile.setVisible(false);
openfile.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
openfile.setVisible(false);
}
});

sizechoice=new Choice();
sizechoice.add("1");
sizechoice.add("2");
sizechoice.add("4");
sizechoice.add("6");
sizechoice.add("8");
sizechoice.addItemListener(this);

colorchoice=new Choice();
colorchoice.add("black");
colorchoice.add("red");
colorchoice.add("blue");
colorchoice.add("green");
colorchoice.addItemListener(this);

pen.addActionListener(this);
line.addActionListener(this);
ellipse.addActionListener(this);
rect.addActionListener(this);
clear.addActionListener(this);
colorboard.addActionListener(this);
storebutton.addActionListener(this);
openbutton.addActionListener(this);

panel=new Panel();

panel.add(storebutton);
panel.add(openbutton);

panel.add(pen);
panel.add(line);
panel.add(ellipse);
panel.add(rect);
panel.add(clear);

panel.add(sizechoice);
panel.add(pensize);

panel.add(colorchoice);
panel.add(pencolor);
panel.add(colorboard);

add(panel,BorderLayout.NORTH);
setBounds(100,100,700,600);
setVisible(true);

addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
});

/**
* 添加鼠标事件的监听器，否则，鼠标的移动和点击都将无法识别！
* */
addMouseListener(this);
addMouseMotionListener(this);
}
public void paint(Graphics g)
{
Graphics2D g2d=(Graphics2D)g;
if(flagtool==2)
{ //qing chu
g.clearRect(0,0,getSize().width,getSize().height);
}
for(int i=0;i<points.size()-1;i++)
{
p1=(OnePoint)points.elementAt(i);
p2=(OnePoint)points.elementAt(i+1);

g2d.setColor(p1.c); //////////////需要使用Graphics2D从Graphics类中继承下来的方法 setColor（）设置当前的颜色
size=new BasicStroke(p1.border,BasicStroke.CAP_BUTT,BasicStroke.JOIN_BEVEL);
g2d.setStroke(size);

if(p1.tool==p2.tool)
{
switch(p1.tool)
{
case 0:
Line2D.Double line1=new Line2D.Double(p1.x,p1.y,p2.x,p2.y);
g2d.draw(line1);
break;
case 1:
Line2D.Double line2=new Line2D.Double(p1.x,p1.y,p2.x,p2.y);
g2d.draw(line2);
break;
case 3:
Ellipse2D.Double 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 4:
Rectangle2D.Double rect=new Rectangle2D.Double(p1.x,p1.y,Math.abs(p2.x-p1.x),Math.abs(p2.y-p1.y));
g2d.draw(rect);
break;
default:
}
}
}
}
public void mouseClicked(MouseEvent e) {}
public void mouseEntered(MouseEvent e) {}
public void mouseExited(MouseEvent e) {}
public void mousePressed(MouseEvent e) //鼠标点下时候，将当前的点信息记录
{
mode=0;
p[0]=e.getPoint();
OnePoint pp1=new OnePoint(e.getX(),e.getY(),flagtool,flagcolor,border);
points.addElement(pp1);
//repaint();
}
public void mouseReleased(MouseEvent e) //鼠标松开时候，如果是画笔，则当前截断，是其余状态记下一枚点信息
{
mode=1;
if(flagtool==0)
{
points.addElement(new OnePoint(-1,-1,22,flagcolor,border));
}
else
{
OnePoint pp2=new OnePoint(e.getX(),e.getY(),flagtool,flagcolor,border);
points.addElement(pp2);
points.add(new OnePoint(-1,-1,22,flagcolor,border));
}
repaint();
}

public void itemStateChanged(ItemEvent e)
{
if(e.getSource()==colorchoice)
{
String selected=colorchoice.getSelectedItem();
if(selected=="black"){flagcolor=new Color(0,0,0); }
else if(selected=="red"){flagcolor=new Color(255,0,0); }
else if(selected=="blue"){ flagcolor=new Color(0,0,255);}
else if(selected=="green"){ flagcolor=new Color(0,255,0); }
}
else if(e.getSource()==sizechoice)
{
String selected=sizechoice.getSelectedItem();
if (selected=="1"){ border=1; }
else if(selected=="2"){ border=2*2; }
else if(selected=="4"){ border=4*2; }
else if(selected=="6"){ border=6*2; }
else if(selected=="8"){ border=8*2; }
}
}
/*public void update(Graphics g) { //@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@
paint(g);
} */
public void actionPerformed(ActionEvent e)
{
// TODO Auto-generated method stub
if(e.getSource()==pen){flagtool=0; }
else if(e.getSource()==line){ flagtool=1; }
else if(e.getSource()==clear)
{
flagtool=2;
points.removeAllElements();
repaint(); //此语要有，否则今生无法删除！
}
else if(e.getSource()==ellipse){ flagtool=3; }
else if(e.getSource()==rect){ flagtool=4; }
else if(e.getSource()==colorboard)
{
/*
* 使用 javax.swing.×包中的 JColorChooser 类的静态方法showDialog（Component component，String title，Color color ），
* 该方法的参数，component是当前显示对话框的父框架，color是设置调色板初始的被选颜色
*
* 该方法返回被选的颜色，类型为Color
* */
Color color=JColorChooser.showDialog(this, "调色板",flagcolor);
flagcolor=color;
}
else if(e.getSource()==openbutton)
{
openfile.setVisible(true);
if(openfile.getFile()!=null)
{
int temp=flagtool;
flagtool=2;
repaint();
try{
points.removeAllElements();
File file=new File(openfile.getDirectory(),openfile.getFile());
filein=new FileInputStream(file);
objectin=new ObjectInputStream(filein);
points=(Vector)objectin.readObject();
objectin.close();
filein.close();
flagtool=temp;
repaint();
}
catch(Exception ee){ System.out.println(ee.toString()); }
}
}
else if(e.getSource()==storebutton)
{
storefile.setVisible(true);
if(storefile.getFile()!=null)
{
try {
File file=new File(storefile.getDirectory(),storefile.getFile());
fileout=new FileOutputStream(file);
objectout=new ObjectOutputStream(fileout);
objectout.writeObject(points);
objectout.close();
fileout.close();
repaint();
}
catch (FileNotFoundException e1)
{
System.out.println(e1.toString());
e1.printStackTrace();
} catch (IOException ee) {
System.out.println(ee.toString());
ee.printStackTrace();
}
}
}
}

public void mouseDragged(MouseEvent e) //鼠标拖动时候，//当且仅当 flagtool＝＝0，或者表示为橡皮的时候
//才将拖动过程中涉及到的点全部记录下来，并且调用repain()方法，重画当前
// TODO Auto-generated method stub
{
if(flagtool==0)
{
OnePoint pp3=new OnePoint(e.getX(),e.getY(),flagtool,flagcolor,border);
points.addElement(pp3);
repaint();
}
if(flagtool==1)
{
OnePoint pp3=new OnePoint(e.getX(),e.getY(),flagtool,flagcolor,border);
repaint();
}
}

public void mouseMoved(MouseEvent e) {
// TODO Auto-generated method stub
}

}

Answer 2

package draw;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.io.*;
import java.util.*;
import javax.swing.*;

//the point
//impress the info of one point,the x and y

class OnePoint implements Serializable
{
int x;
int y;
int tool;
Color c;
int border;
public OnePoint(int x,int y,int tool,Color cc,int border)
{
this.x=x;
this.y=y;
this.tool=tool;
this.c=cc;
this.border=border;
}
public static void main(String[] args)
{
DrawingBoard oneBorder=new DrawingBoard();
}
}

class DrawingBoard extends Frame implements MouseListener,ItemListener,ActionListener,MouseMotionListener
{
Button pen,line,ellipse,rect,clear,colorboard,storebutton,openbutton;
Choice sizechoice,colorchoice ;
Label pensize, pencolor;
Panel panel ;
FileDialog storefile, openfile;
FileInputStream filein;
FileOutputStream fileout;
ObjectInputStream objectin;
ObjectOutputStream objectout;

int mode=0;
int flagtool=0;
Color flagcolor;
int border;
BasicStroke size;
private Point2D[] p=new Point2D[3];;

OnePoint p1,p2;
Vector<OnePoint> points=new Vector<OnePoint>();
public DrawingBoard()
{
pen=new Button("画笔");
line=new Button("直线");
ellipse=new Button("圆");
rect=new Button("矩形");
clear=new Button("清除");
colorboard=new Button("调色板");
storebutton=new Button("存储文件");
openbutton=new Button("打开文件");

pensize=new Label("画笔大小");
pencolor=new Label("画笔颜色");

storefile=new FileDialog(this,"存储文件",FileDialog.SAVE);
storefile.setVisible(false);
storefile.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
storefile.setVisible(false);
}
});
openfile=new FileDialog(this,"打开文件",FileDialog.LOAD);
openfile.setVisible(false);
openfile.addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
openfile.setVisible(false);
}
});

sizechoice=new Choice();
sizechoice.add("1");
sizechoice.add("2");
sizechoice.add("4");
sizechoice.add("6");
sizechoice.add("8");
sizechoice.addItemListener(this);

colorchoice=new Choice();
colorchoice.add("black");
colorchoice.add("red");
colorchoice.add("blue");
colorchoice.add("green");
colorchoice.addItemListener(this);

pen.addActionListener(this);
line.addActionListener(this);
ellipse.addActionListener(this);
rect.addActionListener(this);
clear.addActionListener(this);
colorboard.addActionListener(this);
storebutton.addActionListener(this);
openbutton.addActionListener(this);

panel=new Panel();

panel.add(storebutton);
panel.add(openbutton);

panel.add(pen);
panel.add(line);
panel.add(ellipse);
panel.add(rect);
panel.add(clear);

panel.add(sizechoice);
panel.add(pensize);

panel.add(colorchoice);
panel.add(pencolor);
panel.add(colorboard);

add(panel,BorderLayout.NORTH);
setBounds(100,100,700,600);
setVisible(true);

addWindowListener(new WindowAdapter(){
public void windowClosing(WindowEvent e){
System.exit(0);
}
});

/**
* 添加鼠标事件的监听器，否则，鼠标的移动和点击都将无法识别！
* */
addMouseListener(this);
addMouseMotionListener(this);
}
public void paint(Graphics g)
{
Graphics2D g2d=(Graphics2D)g;
if(flagtool==2)
{ //qing chu
g.clearRect(0,0,getSize().width,getSize().height);
}
for(int i=0;i<points.size()-1;i++)
{
p1=(OnePoint)points.elementAt(i);
p2=(OnePoint)points.elementAt(i+1);

g2d.setColor(p1.c); //////////////需要使用Graphics2D从Graphics类中继承下来的方法 setColor（）设置当前的颜色