package drawingpanel;import java.awt.*;import java.awt.geom.*;import java.awt.event.*;import javax.swing.*;import java.io.*;import java.util.*;public class MiniDrawPad extends JFrame     //主類，擴展了JFrame類，用來生成主界面 {  private ObjectInputStream  input;  private ObjectOutputStream output; //定義輸入輸出流，用來調用和保存圖像文件  private JButton choices[];         //按鈕數組，存放以下名稱的功能按鈕  private String names[]={          "New",          "Open",          "Save",    //這三個是基本操作按鈕，包括"新建"、"打開"、"保存"        /*接下來是我們的畫圖板上面有的基本的幾個繪圖單元按鈕*/          "Pencil",		//鉛筆畫，也就是用鼠標拖動著隨意繪圖          "Line",		//繪制直線          "Rect",		//繪制空心矩形          "fRect",		//繪制以指定顏色填充的實心矩形          "Oval",		//繪制空心橢圓          "fOval",		//繪制以指定顏色填充的實心橢圓          "Circle",		//繪制圓形          "fCircle",	//繪制以指定顏色填充的實心圓形          "RoundRect",	//繪制空心圓角矩形          "frRect",		//繪制以指定顏色填充的實心圓角矩形          "Rubber",		//橡皮擦，可用來擦去已經繪制好的圖案          "Color",		//選擇顏色按鈕，可用來選擇需要的顏色          "Stroke",		//選擇線條粗細的按鈕，輸入需要的數值可以實現繪圖線條粗細的變化          "Word"		//輸入文字按鈕，可以在繪圖板上實現文字輸入          };  private String styleNames[]={            " 宋體 " , " 隸書 " , " 華文彩云 " , " 仿宋_GB2312 " , " 華文行楷 " ,            " 方正舒體 " , " Times New Roman " , " Serif " , " Monospaced " ,            " SonsSerif " , " Garamond "            };            //可供選擇的字體項                          //當然這里的靈活的結構可以讓讀者自己隨意添加系統支持的字體  private Icon items[];  private String tipText[]={                  //這里是鼠標移動到相應按鈕上面上停留時給出的提示說明條                  //讀者可以參照上面的按鈕定義對照著理解                "Draw a new picture",                "Open a saved picture",                "Save current drawing",                "Draw at will",                "Draw a straight line",                "Draw a rectangle",                "Fill a ractangle",                "Draw an oval",                "Fill an oval",                "Draw a circle",                "Fill a circle",                "Draw a round rectangle",                "Fill a round rectangle",                "Erase at will",                "Choose current drawing color",                "Set current drawing stroke",                "Write down what u want"              };  JToolBar buttonPanel ;		       //定義按鈕面板  private JLabel statusBar;            //顯示鼠標狀態的提示條  private DrawPanel drawingArea;       //畫圖區域  private int width=800,height=550;    //定義畫圖區域初始大小  drawings[] itemList=new drawings[5000]; //用來存放基本圖形的數組  private int currentChoice=3;            //設置默認畫圖狀態為隨筆畫  int index=0;                         //當前已經繪制的圖形數目  private Color color=Color.black;     //當前畫筆顏色  int R,G,B;                           //用來存放當前色彩值  int f1,f2;                  //用來存放當前字體風格  String style1;              //用來存放當前字體  private float stroke=1.0f;  //設置畫筆粗細，默認值為1.0f  JCheckBox bold,italic;      //定義字體風格選擇框                              //bold為粗體，italic為斜體，二者可以同時使用  JComboBox styles;  public MiniDrawPad()        //構造函數  {   super("Drawing Pad");   JMenuBar bar=new JMenuBar();		//定義菜單條   JMenu fileMenu=new JMenu("File");   fileMenu.setMnemonic('F');//新建文件菜單條   JMenuItem newItem=new JMenuItem("New");   newItem.setMnemonic('N');   newItem.addActionListener(          new ActionListener(){                  public void actionPerformed(ActionEvent e)                  {                   newFile();		//如果被觸發，則調用新建文件函數段                  }          }   );   fileMenu.add(newItem);//保存文件菜單項   JMenuItem saveItem=new JMenuItem("Save");   saveItem.setMnemonic('S');   saveItem.addActionListener(          new ActionListener(){                  public void actionPerformed(ActionEvent e)                  {                   saveFile();		//如果被觸發，則調用保存文件函數段                  }          }   );   fileMenu.add(saveItem);//打開文件菜單項   JMenuItem loadItem=new JMenuItem("Load");   loadItem.setMnemonic('L');   loadItem.addActionListener(          new ActionListener(){                  public void actionPerformed(ActionEvent e)                  {                   loadFile();		//如果被觸發，則調用打開文件函數段                  }          }   );   fileMenu.add(loadItem);   fileMenu.addSeparator();//退出菜單項   JMenuItem exitItem=new JMenuItem("Exit");   exitItem.setMnemonic('X');   exitItem.addActionListener(          new ActionListener(){                  public void actionPerformed(ActionEvent e)                  {                   System.exit(0);	//如果被觸發，則退出畫圖板程序                  }          }   );   fileMenu.add(exitItem);   bar.add(fileMenu);//設置顏色菜單條   JMenu colorMenu=new JMenu("Color");   colorMenu.setMnemonic('C');//選擇顏色菜單項   JMenuItem colorItem=new JMenuItem("Choose Color");   colorItem.setMnemonic('O');   colorItem.addActionListener(           new ActionListener(){                   public void actionPerformed(ActionEvent e)                   {                    chooseColor();	//如果被觸發，則調用選擇顏色函數段                   }       }      );   colorMenu.add(colorItem);   bar.add(colorMenu);//設置線條粗細菜單條    JMenu strokeMenu=new JMenu("Stroke");    strokeMenu.setMnemonic('S');//設置線條粗細菜單項    JMenuItem strokeItem=new JMenuItem("Set Stroke");    strokeItem.setMnemonic('K');    strokeItem.addActionListener(           new ActionListener(){                   public void actionPerformed(ActionEvent e)                    {                     setStroke();                     }                   }              );           strokeMenu.add(strokeItem);           bar.add(strokeMenu);//設置提示菜單條    JMenu helpMenu=new JMenu("Help");    helpMenu.setMnemonic('H');//設置提示菜單項    JMenuItem aboutItem=new JMenuItem("About this Drawing Pad!");    aboutItem.setMnemonic('A');    aboutItem.addActionListener(           new ActionListener(){                   public void actionPerformed(ActionEvent e)                    {                     JOptionPane.showMessageDialog(null,                        "This is a mini drawing pad!\nCopyright (c) 2002 Tsinghua University ",                        " 畫圖板程序說明 ",                         JOptionPane.INFORMATION_MESSAGE );                     }                   }              );    helpMenu.add(aboutItem);    bar.add(helpMenu);    items=new ImageIcon[names.length];//創建各種基本圖形的按鈕    drawingArea=new DrawPanel();    choices=new JButton[names.length];    buttonPanel = new JToolBar( JToolBar.VERTICAL ) ;    buttonPanel = new JToolBar( JToolBar.HORIZONTAL) ;    ButtonHandler handler=new ButtonHandler();    ButtonHandler1 handler1=new ButtonHandler1();//導入我們需要的圖形圖標，這些圖標都存放在與源文件相同的目錄下面    for(int i=0;i<choices.length;i++)    {//items[i]=new ImageIcon( MiniDrawPad.class.getResource(names[i] +".gif"));                       //如果在jbuilder下運行本程序，則應該用這條語句導入圖片     items[i]=new ImageIcon(names[i] + ".gif");                   //默認的在jdk或者jcreator下運行，用此語句導入圖片     choices[i]=new JButton("",items[i]);     choices[i].setToolTipText(tipText[i]);     buttonPanel.add(choices[i]);    }//將動作偵聽器加入按鈕里面    for(int i=3;i<choices.length-3;i++)    {     choices[i].addActionListener(handler);    }    choices[0].addActionListener(          new ActionListener(){                  public void actionPerformed(ActionEvent e)                  {                   newFile();                  }          }     );    choices[1].addActionListener(          new ActionListener(){                  public void actionPerformed(ActionEvent e)                  {                   loadFile();                  }          }     );    choices[2].addActionListener(          new ActionListener(){                  public void actionPerformed(ActionEvent e)                  {                   saveFile();                  }          }     );    choices[choices.length-3].addActionListener(handler1);    choices[choices.length-2].addActionListener(handler1);    choices[choices.length-1].addActionListener(handler1);//字體風格選擇    styles=new JComboBox(styleNames);    styles.setMaximumRowCount(8);    styles.addItemListener(            new ItemListener(){                    public void itemStateChanged(ItemEvent e)                    {                      style1=styleNames[styles.getSelectedIndex()];                    }               }            );//字體選擇    bold=new JCheckBox("BOLD");    italic=new JCheckBox("ITALIC");    checkBoxHandler cHandler=new checkBoxHandler();    bold.addItemListener(cHandler);    italic.addItemListener(cHandler);    JPanel wordPanel=new JPanel();    buttonPanel.add(bold);    buttonPanel.add(italic);    buttonPanel.add(styles);    styles.setMinimumSize(  new Dimension ( 50, 20 ) );    styles.setMaximumSize(new Dimension ( 100, 20 ) );    Container c=getContentPane();    super.setJMenuBar( bar );    c.add(buttonPanel,BorderLayout.NORTH);    c.add(drawingArea,BorderLayout.CENTER);    statusBar=new JLabel();    c.add(statusBar,BorderLayout.SOUTH);    statusBar.setText("     Welcome To The Little Drawing Pad!!!  :)");    createNewItem();    setSize(width,height);    show();  }//按鈕偵聽器ButtonHanler類，內部類，用來偵聽基本按鈕的操作public class ButtonHandler implements ActionListener {  public void actionPerformed(ActionEvent e)  {   for(int j=3;j<choices.length-3;j++)   {      if(e.getSource()==choices[j])         {currentChoice=j;          createNewItem();          repaint();}        }    } }//按鈕偵聽器ButtonHanler1類，用來偵聽顏色選擇、畫筆粗細設置、文字輸入按鈕的操作public class ButtonHandler1 implements ActionListener {  public void actionPerformed(ActionEvent e)  {    if(e.getSource()==choices[choices.length-3])         {chooseColor();}    if(e.getSource()==choices[choices.length-2])         {setStroke();}    if(e.getSource()==choices[choices.length-1])         {JOptionPane.showMessageDialog(null,             "Please hit the drawing pad to choose the word input position",             "Hint",JOptionPane.INFORMATION_MESSAGE );          currentChoice=14;          createNewItem();          repaint();          }    } }//鼠標事件mouseA類，繼承了MouseAdapter，用來完成鼠標相應事件操作 class mouseA extends MouseAdapter {   public void mousePressed(MouseEvent e)    {statusBar.setText("     Mouse Pressed @:[" + e.getX() +                              ", " + e.getY() + "]");//設置狀態提示     itemList[index].x1=itemList[index].x2=e.getX();     itemList[index].y1=itemList[index].y2=e.getY();    //如果當前選擇的圖形是隨筆畫或者橡皮擦，則進行下面的操作    if(currentChoice==3||currentChoice==13)    {     itemList[index].x1=itemList[index].x2=e.getX();     itemList[index].y1=itemList[index].y2=e.getY();     index++;     createNewItem();     }    //如果當前選擇的圖形式文字輸入，則進行下面操作     if(currentChoice==14)     {      itemList[index].x1=e.getX();      itemList[index].y1=e.getY();      String input;      input=JOptionPane.showInputDialog(          "Please input the text you want!");      itemList[index].s1=input;      itemList[index].x2=f1;      itemList[index].y2=f2;      itemList[index].s2=style1;      index++;      currentChoice=14;      createNewItem();      drawingArea.repaint();      }    }   public void mouseReleased(MouseEvent e)    {statusBar.setText("     Mouse Released @:[" + e.getX() +                              ", " + e.getY() + "]");    if(currentChoice==3||currentChoice==13)    {     itemList[index].x1=e.getX();     itemList[index].y1=e.getY();    }     itemList[index].x2=e.getX();     itemList[index].y2=e.getY();     repaint();     index++;     createNewItem();    }   public void mouseEntered(MouseEvent e)   {           statusBar.setText("     Mouse Entered @:[" + e.getX() +                              ", " + e.getY() + "]");           }   public void mouseExited(MouseEvent e)   {           statusBar.setText("     Mouse Exited @:[" + e.getX() +                              ", " + e.getY() + "]");           }  }//鼠標事件mouseB類繼承了MouseMotionAdapter，用來完成鼠標拖動和鼠標移動時的相應操作 class mouseB extends MouseMotionAdapter {  public void mouseDragged(MouseEvent e)  {statusBar.setText("     Mouse Dragged @:[" + e.getX() +                              ", " + e.getY() + "]");   if(currentChoice==3||currentChoice==13)   {    itemList[index-1].x1=itemList[index].x2=itemList[index].x1=e.getX();