JavaSwing图形界面编程之画图程序

package three.day.frame;

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


class Point1 implements Serializable {
int x, y;// 鼠标的位置
Color col;// 画图选择的颜色
int tool;// 画图选择画哪种图形
int boarder;// 线条宽度


Point1(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 paintboard1 extends Frame implements ActionListener, MouseMotionListener,
MouseListener, ItemListener {
int x = -1, y = -1;// 初始化鼠标位置
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, BasicStroke.CAP_BUTT,
BasicStroke.JOIN_BEVEL);// 画笔粗细
Point1 cutflag = new Point1(-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;


paintboard1(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();
ColChoice.add("black");
ColChoice.add("red");
ColChoice.add("blue");
ColChoice.add("green");
ColChoice.addItemListener(this);
// 画笔大小选择
SizeChoice = new Choice();
SizeChoice.add("1");
SizeChoice.add("3");
SizeChoice.add("5");
SizeChoice.add("7");
SizeChoice.add("9");
SizeChoice.addItemListener(this);
// 橡皮大小选择
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("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
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);


颜色 = new Label("画笔颜色", Label.CENTER);
大小B = new Label("画笔大小", Label.CENTER);
大小E = new Label("橡皮大小", Label.CENTER);
// 面板添加组件
toolPanel.add(openPic);
toolPanel.add(savePic);


toolPanel.add(pen);
toolPanel.add(drLine);
toolPanel.add(drCircle);
toolPanel.add(drRect);


toolPanel.add(颜色);
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(230, 50, 900, 650);
setVisible(true);
validate();
// dialog for save and load


openPicture = new FileDialog(this, "打开图画", FileDialog.LOAD);
openPicture.setVisible(false);
savePicture = new FileDialog(this, "保存图画", 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) {
System.out.println("paint");
Graphics2D g2d = (Graphics2D) g;


Point1 p1, p2;


n = paintInfo.size();


if (toolFlag == 2)
g2d.clearRect(0, 0, getSize().width - 100, getSize().height - 100);// 清除


for (int i = 0; i < n - 1; i++) {
p1 = (Point1) paintInfo.elementAt(i);
p2 = (Point1) 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:// 画笔


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:// 画直线
Line2D line2 = new Line2D.Double(p1.x, p1.y, p2.x, p2.y);
g2d.draw(line2);
break;


case 4:// 画圆
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:// 画矩形
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:// 截断，跳过
i = i + 1;
break;


default:
}// end switch
}// end if
}// end for
}


public void itemStateChanged(ItemEvent e) {
System.out.println("itemStateChanged");
if (e.getSource() == ColChoice)// 预选颜色
{
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)// 画笔大小
{
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) {
System.out.println("mouseDragged");
Point1 p1;
switch (toolFlag) {
case 0:// 画笔
x = (int) e.getX();
y = (int) e.getY();
p1 = new Point1(x, y, c, toolFlag, con);
paintInfo.addElement(p1);
repaint();
break;


case 1:// 橡皮
x = (int) e.getX();
y = (int) e.getY();
p1 = new Point1(x, y, null, toolFlag, Econ);
paintInfo.addElement(p1);
repaint();
break;


default:
}
}


public void mouseMoved(MouseEvent e) {
}


public void update(Graphics g) {
System.out.println("update");
paint(g);
}


public void mousePressed(MouseEvent e) {
System.out.println("mousePressed");
Point1 p2;
switch (toolFlag) {
case 3:// 直线
x = (int) e.getX();
y = (int) e.getY();
p2 = new Point1(x, y, c, toolFlag, con);
paintInfo.addElement(p2);
break;


case 4: // 圆
x = (int) e.getX();
y = (int) e.getY();
p2 = new Point1(x, y, c, toolFlag, con);
paintInfo.addElement(p2);
break;


case 5: // 矩形
x = (int) e.getX();
y = (int) e.getY();
p2 = new Point1(x, y, c, toolFlag, con);
paintInfo.addElement(p2);
break;


default:
}
}


public void mouseReleased(MouseEvent e) {
System.out.println("mouseReleased");
Point1 p3;
switch (toolFlag) {
case 0: // 画笔
paintInfo.addElement(cutflag);
break;


case 1: // eraser
paintInfo.addElement(cutflag);
break;


case 3: // 直线
x = (int) e.getX();
y = (int) e.getY();
p3 = new Point1(x, y, c, toolFlag, con);
paintInfo.addElement(p3);
paintInfo.addElement(cutflag);
repaint();
break;


case 4: // 圆
x = (int) e.getX();
y = (int) e.getY();
p3 = new Point1(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 Point1(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) {
System.out.println("actionPerformed");
if (e.getSource() == pen)// 画笔
{
System.out.println("pen");
toolFlag = 0;
}


if (e.getSource() == eraser)// 橡皮
{
System.out.println("eraser");
toolFlag = 1;
}


if (e.getSource() == clear)// 清除
{
System.out.println("clear");
toolFlag = 2;
paintInfo.removeAllElements();
repaint();
}


if (e.getSource() == drLine)// 画线
{
System.out.println("drLine");
toolFlag = 3;
}


if (e.getSource() == drCircle)// 画圆
{
System.out.println("drCircle");
toolFlag = 4;
}


if (e.getSource() == drRect)// 画矩形
{
System.out.println("drRect");
toolFlag = 5;
}


if (e.getSource() == colchooser)// 调色板
{
System.out.println("colchooser");
Color newColor = JColorChooser.showDialog(this, "我的调色板", c);
c = newColor;
}


if (e.getSource() == openPic)// 打开图画
{


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)// 保存图画
{
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 paintboard1


public class PaintDemo01 {
public static void main(String args[]) {
new paintboard1("画图程序");
}
}