repaint(); }
public void mouseMoved(MouseEvent e)
{statusBar.setText(\ \ }
//选择字体风格时候用到的事件侦听器类，加入到字体风格的选择框中 private class checkBoxHandler implements ItemListener {
public void itemStateChanged(ItemEvent e) {
if(e.getSource()==bold)
if(e.getStateChange()==ItemEvent.SELECTED) f1=Font.BOLD; else
f1=Font.PLAIN;
if(e.getSource()==italic)
if(e.getStateChange()==ItemEvent.SELECTED) f2=Font.ITALIC; else
f2=Font.PLAIN; } }
//画图面板类，用来画图
class DrawPanel extends JPanel {
public DrawPanel() {
setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR)); setBackground(Color.white); addMouseListener(new mouseA()); addMouseMotionListener(new mouseB()); }
public void paintComponent(Graphics g) {
super.paintComponent(g);
Graphics2D g2d=(Graphics2D)g; //定义画笔 int j=0;
while (j<=index) {
draw(g2d,itemList[j]);
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j++; }
}
void draw(Graphics2D g2d,drawings i) {
i.draw(g2d);//将画笔传入到各个子类中，用来完成各自的绘图 } }
//新建一个画图基本单元对象的程序段 void createNewItem()
{ if(currentChoice==14)//进行相应的游标设置
drawingArea.setCursor(Cursor.getPredefinedCursor(Cursor.TEXT_CURSOR));
else
drawingArea.setCursor(Cursor.getPredefinedCursor(Cursor.CROSSHAIR_CURSOR));
switch (currentChoice) {
case 3:
itemList[index]=new Pencil(); break; case 4:
itemList[index]=new Line(); break; case 5:
itemList[index]=new Rect(); break; case 6:
itemList[index]=new fillRect(); break; case 7:
itemList[index]=new Oval(); break; case 8:
itemList[index]=new fillOval(); break; case 9:
itemList[index]=new Circle(); break; case 10:
itemList[index]=new fillCircle(); break; case 11:
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itemList[index]=new RoundRect(); break; case 12:
itemList[index]=new fillRoundRect(); break; case 13:
itemList[index]=new Rubber(); break; case 14:
itemList[index]=new Word(); break; }
itemList[index].type=currentChoice; itemList[index].R=R; itemList[index].G=G; itemList[index].B=B;
itemList[index].stroke=stroke; }
//选择当前颜色程序段
public void chooseColor() {
color=JColorChooser.showDialog(MiniDrawPad.this, \ R=color.getRed(); G=color.getGreen(); B=color.getBlue(); itemList[index].R=R; itemList[index].G=G; itemList[index].B=B; }
//选择当前线条粗细程序段 public void setStroke() {
String input;
input=JOptionPane.showInputDialog(
\ stroke=Float.parseFloat(input); itemList[index].stroke=stroke; }
//保存图形文件程序段
public void saveFile() {
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JFileChooser fileChooser=new JFileChooser();
fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY); int result =fileChooser.showSaveDialog(this); if(result==JFileChooser.CANCEL_OPTION) return ;
File fileName=fileChooser.getSelectedFile(); fileName.canWrite();
if (fileName==null||fileName.getName().equals(\
JOptionPane.showMessageDialog(fileChooser,\ \ERROR_MESSAGE); else{ try {
fileName.delete();
FileOutputStream fos=new FileOutputStream(fileName);
output=new ObjectOutputStream(fos); drawings record;
output.writeInt( index );
for(int i=0;i< index ;i++) {
drawings p= itemList[ i ] ; output.writeObject(p);
output.flush(); //将所有图形信息强制转换成父类线性化存储到文件中 } output.close(); fos.close(); }
catch(IOException ioe) {
ioe.printStackTrace(); } } }
//打开一个图形文件程序段 public void loadFile() {
JFileChooser fileChooser=new JFileChooser();
fileChooser.setFileSelectionMode(JFileChooser.FILES_ONLY); int result =fileChooser.showOpenDialog(this); if(result==JFileChooser.CANCEL_OPTION) return ;
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File fileName=fileChooser.getSelectedFile(); fileName.canRead();
if (fileName==null||fileName.getName().equals(\
JOptionPane.showMessageDialog(fileChooser,\ \ERROR_MESSAGE); else { try {
FileInputStream fis=new FileInputStream(fileName);
input=new ObjectInputStream(fis); drawings inputRecord;
int countNumber=0;
countNumber=input.readInt();
for(index=0;index< countNumber ;index++) {
inputRecord=(drawings)input.readObject(); itemList[ index ] = inputRecord ;
}
createNewItem(); input.close(); repaint(); }
catch(EOFException endofFileException){
JOptionPane.showMessageDialog(this,\ \ERROR_MESSAGE ); }
catch(ClassNotFoundException classNotFoundException){ JOptionPane.showMessageDialog(this,\Object\
\ERROR_MESSAGE ); }
catch (IOException ioException){
JOptionPane.showMessageDialog(this,\file\
\ERROR_MESSAGE ); } } }
//新建一个文件程序段
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