diary.java

程序人员在编程过程中如果遇到相关问题可以来这里进行参考

   });
   popup.add(menuItem);
 MouseListener popupListener=new PopupListener(popup);
 textDemo.addMouseListener(popupListener);
 }
   private void newMenuItem(){
         int n;
      Object[] option={"YES","NO","CANCEL"};
      if(changed==true)
      {
          n=JOptionPane.showOptionDialog(null,"你的文件还没保存,你想现在保存吗?",
                  "保存",JOptionPane.YES_NO_CANCEL_OPTION,JOptionPane.QUESTION_MESSAGE,
                  null,option,option[0]);
          switch(n)
          {
              case JOptionPane.YES_OPTION:{
                  doSave(fileName);
                  fileName="";
                 textDemo.setText("");
                  changed=false;
                  break;
              }
              case JOptionPane.NO_OPTION:{
                  fileName="";
                textDemo.setText("");
                  changed=false;
                  break;
              }
              case JOptionPane.CANCEL_OPTION:
                  break;
          }
      }
      else
      {
          fileName="";
        textDemo.setText("");
      }
    }
       
 private void doSave(String fileName)
    {
        FileOutputStream fos=null;
        if(fileName=="")
        {
            doSaveAs();
        }
        else
        {
            String str=textDemo.getText();
            try
            {
                fos=new FileOutputStream(fileName);
                fos.write(str.getBytes());
            }    
           catch(IOException e1)
           {
        }
            finally
            {
                try
                {
                    fos.close();
                }
                catch (IOException e2)
                {
                }
            }
            changed=false;
    }
           
    }
    
    private void doSaveAs()
    {
        FileOutputStream fos=null;
        String str=textDemo.getText();
        FileDialog fileDialog=new FileDialog(this,"Save As...",FileDialog.SAVE);
        fileDialog.setVisible(true);
        if(fileDialog.getFile()==null)
        {
            return;
        }
        fileName=fileDialog.getDirectory()+File.separator+fileDialog.getFile();
        try
        {
            fos=new FileOutputStream(fileName);
            fos.write(str.getBytes());
        }
        catch(IOException e1)
        {
            
        }
        finally
        {try
         {
             fos.close();
         }
         catch(IOException e2)
         {
             
         }
    }
    changed=false;
    
    }
    
     private void openMenuItem()
    {
        FileDialog fileDialog=new FileDialog(this,"Open...",
                FileDialog.LOAD);
        fileDialog.setVisible(true);
        if(fileDialog.getFile()==null)
        {
            return;
        }
        fileName=fileDialog.getDirectory()+File.separator+fileDialog.getFile();
        FileInputStream fis=null;
        String str=null;
 try
 {
            fis=new FileInputStream(fileName);
            int size=fis.available();
            byte[] bytes=new byte[size];
            fis.read(bytes);
            str=new String(bytes);
            
        }
 catch (IOException e1)
 {
 }
   finally{
       try{
           fis.close();
       }
    catch (IOException e2)
    {
   }
      
    }
 
    if(str!=null)
    {
        textDemo.setText(str);
    }
    changed=false;
    }
   private void findMenuItem(ActionEvent e)
   {
           new Finder(this,textDemo).setVisible(true);
   }
    
   private void FcolorMenuItem(ActionEvent e)
   {
      Color newColor=JColorChooser.showDialog(
              this,"选择字体颜色",textDemo.getForeground());
      
      if(newColor!=null)
      {
          textDemo.setForeground(newColor);
      }
   }
   private void BcolorMenuItem(ActionEvent e)
   {
       Color newColor=JColorChooser.showDialog(this,"选择背景颜色",textDemo.getBackground());
       if(newColor!=null)
       {
           textDemo.setBackground(newColor);
       }
   }
   
}   

class PopupListener extends MouseAdapter
    {
       PopupListener(JPopupMenu popupMenu)
       {
           popup=popupMenu;
       }
       public void mousePressed(MouseEvent e)
       {
           maybeShowPopup(e);
       }
      public void mouseReleased(MouseEvent e)
      {
          maybeShowPopup(e);
      }
      private void maybeShowPopup(MouseEvent e){
          if(e.isPopupTrigger())
          {
              popup.show(e.getComponent(),e.getX(),e.getY());
          }
      }
         JPopupMenu popup;
     }
 


 class Finder extends javax.swing.JDialog 
 {
     public Finder(Frame parent, JTextArea textEditor)
 {
     super(parent,true);
     this.textEditor=textEditor;
     initComponents();
     pack();
     setLocationRelativeTo(parent);
     findField.requestFocus();
    
     
 }
     private void initComponents()
     {
         GridBagConstraints gridBagConstriants;
         findPanel=new JPanel();
         findLabel=new JLabel();
         findField=new JTextField();
         buttonPanel=new JPanel();
         findButton=new JButton();
         closeButton=new JButton();
         getContentPane().setLayout(new GridBagLayout());
         setTitle("查找");
         addWindowListener(new WindowAdapter(){
             public void windowClosing(WindowEvent e){
                 closeDialog(e);}
         });
      getAccessibleContext().setAccessibleName("Find Dialog") ;
     getAccessibleContext().setAccessibleDescription("Find dialog.");
    findPanel.setLayout(new GridBagLayout());
    findLabel.setLabelFor(findField);
    findLabel.setText("查找内容:");
    findPanel.add(findLabel,new GridBagConstraints());
    findLabel.getAccessibleContext().setAccessibleDescription("Find text.");
    
    findField.addActionListener(new ActionListener(){
        public void actionPerformed(ActionEvent e){
            findFieldActionPerformed(e);
        }
    });
    GridBagConstraints gridBagConstraints=new GridBagConstraints();
     gridBagConstraints.fill=GridBagConstraints.HORIZONTAL;
     gridBagConstraints.weightx=1.0;
     gridBagConstraints.insets=new Insets(0,5,0,0);
     findPanel.add(findField,gridBagConstraints);
     findField.getAccessibleContext().setAccessibleName("Find Field") ;
     getAccessibleContext().setAccessibleDescription("Find field.");
     
     gridBagConstraints=new GridBagConstraints();
     gridBagConstraints.fill=GridBagConstraints.BOTH;
     gridBagConstraints.insets=new Insets(11,12,0,11);
     getContentPane().add(findPanel,gridBagConstraints);
     buttonPanel.setLayout(new GridBagLayout());
     findButton.setMnemonic('f');
     findButton.setText("查找");
     findButton.addActionListener(new ActionListener(){
         public void actionPerformed(ActionEvent e){
             findButtonActionPerformed(e);
         }
     });
     buttonPanel.add(findButton,new GridBagConstraints());
     closeButton.setMnemonic('c');
     closeButton.setText("关闭");
     
     gridBagConstraints=new GridBagConstraints();
     gridBagConstraints.insets=new Insets(0,5,0,0);
     buttonPanel.add(closeButton,gridBagConstraints);
     gridBagConstraints=new GridBagConstraints();
       gridBagConstraints.gridx=0;
       gridBagConstraints.gridy=1;
      gridBagConstraints.anchor=GridBagConstraints.SOUTHEAST;
       gridBagConstraints.insets=new Insets(17,12,11,11);
       getContentPane().add(buttonPanel,gridBagConstraints);
             
     }
     private void findFieldActionPerformed(ActionEvent e){
         if(findField.getText().length()>0)
         {
             findButton.doClick();
         }
     }
     private void findButtonActionPerformed(ActionEvent e)
     {
         String text=textEditor.getText();
         String textToFind=findField.getText();
         if(!"".equals(textToFind))
         {
             int index=text.indexOf(textToFind);
             if(index!=-1)
             {
                 textEditor.setCaretPosition(index);
                 closeDialog(null);
             }
             else 
             {
                 Toolkit.getDefaultToolkit().beep();
                
             }
         }
     }
     private void closeButtonActionPerformed(ActionEvent e)
     {
         closeDialog(null);
     }
     private void closeDialog(WindowEvent e)
     {
         setVisible(false);
         dispose();
     }

   
     
     private javax.swing.JPanel buttonPanel;
     private javax.swing.JButton closeButton;
     private javax.swing.JButton findButton;
     private javax.swing.JTextField findField;
     private javax.swing.JLabel findLabel;
      private javax.swing.JPanel findPanel;
     private javax.swing.JTextArea textEditor;
 } 
class About extends javax.swing.JDialog
 {
     public About(Frame parent)
     {
         super(parent,true);
         initComponents();
         pack();
         setLocationRelativeTo(parent);
     }
     private void initComponents()
     {
       JTextField jTextField1=new JTextField();
         setTitle("关于记事本");
          addWindowListener(new WindowAdapter(){
              public void windowClosing(WindowEvent e){
                  closeDialog(e);
              }
              
          });
          getAccessibleContext().setAccessibleName("About Dialog");
          getAccessibleContext().setAccessibleDescription("About dialog.");
          jTextField1.setEditable(false);
          jTextField1.setText("这是一个简单的文本编辑器");
          getContentPane().add(jTextField1,BorderLayout.CENTER);
          jTextField1.getAccessibleContext().setAccessibleName("About Text");
          jTextField1.getAccessibleContext().setAccessibleDescription("About text.");
     }   
     private void closeDialog(WindowEvent e)
     {
         setVisible(false);
         dispose();
     }
 }