Question

对高手来说应该很简单吧，我的作业···

作业要求：

功能说明：
file菜单—包括两个菜单项：
open:：打开.gif的图形文件，并显示在窗口里。文
件名在下面的编辑框中给出
exit：结束程序。
edit菜单—包括两个菜单项：
paint：在窗口中画图形，图形的类型及颜色分别由下面的
复选框及选择按扭指定。
clear：清空窗口内容。

我只会构造选项
JMenuBar menubar=new JMenuBar();
JMenu file=menubar.add(new JMenu("File"));
file.add(new JMenuItem("open")).addActionListener(this);
file.add(new JMenuItem("exit")).addActionListener(this);
Jmenu edit=menubar.add(new JMenu("Edit"));
edit.add(new JMenuItem("paint")).addActionListener(this);
edit.add(new JMenuItem("clear")).addActionListener(this);
但这些open、exit之类的功能我不知道如何实现···

程序的大概结构是

————————————————————————————菜单栏
————
————
————————————————————————————图片区
————
————
--文本域--|-选项窗格（选择画椭圆、三角形、矩形）-|-三个单选按钮（红、黄、绿）--

谢谢各位了！今晚之前的话追加100分！

Answer 1

很高兴为您解答，希望能够对您起到帮助！
再这里祝您；身体健康，万事如意，福如东海，寿比南山！
娶个好老婆，找个好工作，出门就拣钱！！

Answer 2

今晚是哪天晚上？

Answer 3

顶楼的哥哥太愉快了

Answer 4

一个画板程序,已实现大多数功能了.

package baidutest;

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;// 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

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();
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(60, 60, 900, 600);
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) {
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:// 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) {
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) {
Point p1;
switch (toolFlag) {
case 0:// 画笔
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:// 直线
x = (int) e.getX();
y = (int) e.getY();
p2 = new Point(x, y, c, toolFlag, con);
paintInfo.addElement(p2);
break;

case 4: // 圆
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:// 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 Point(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 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)// 画笔
{
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)// 画线
{
toolFlag = 3;
}

if (e.getSource() == drCircle)// 画圆
{
toolFlag = 4;
}

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

if (e.getSource() == colchooser)// 调色板
{
Color newColor = JColorChooser.showDialog(this, "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 paintboard

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