finder.java

简单的文本编辑器,文件操作能够实现：新建文档、保存文档、打开文档、关闭文档、页面设置、打印预览、打印设置、打印等。编辑操作能够实现对文本内容的选择、剪切、复制、粘贴、查找、替换等。

package mytexteditor.texteditor;

 
 
// 查找对话框类，实现在text文档中的查找相应的文本串的位置，
// 查找成功，返回文本串在文件中的位置；不成功，则什么也不做
public class Finder extends javax.swing.JDialog 
{   
    //查找对话框类的构造器    
    public Finder(java.awt.Frame parent, javax.swing.JTextArea textEditor)
    {
        super(parent, true);        
        this.textEditor = textEditor;        
        initComponents();        
        pack();        
        setLocationRelativeTo(parent);        
        findField.requestFocus();
        
    } 
    
    //initComponents 方法由constructor调用，
    // 对对话框的GUI组件进行初始化；
    private void initComponents() 
    {
    	
        java.awt.GridBagConstraints gridBagConstraints;
        
        //创建装载标签findLabel和文本域findField的findPanel 对象
        
        findPanel = new javax.swing.JPanel();           
        findLabel = new javax.swing.JLabel();  //创建标签findLabel对象
        findField = new javax.swing.JTextField(); //创建文本域findField对象
        buttonPanel = new javax.swing.JPanel(); //创建装载按钮的buttonPanel 对象
        findButton = new javax.swing.JButton(); //创建findButton对象
        closeButton = new javax.swing.JButton();  //创建closeButton对象 
        
        //设置内容板的布局为GridBagLayout              
        getContentPane().setLayout(new java.awt.GridBagLayout());

        setTitle("查找"); //设置对话框的标题
        
        //设置窗口的监听器
        
        addWindowListener(new java.awt.event.WindowAdapter(){
              public void windowClosing(java.awt.event.WindowEvent evt){
                   closeDialog(evt);}
         });

        getAccessibleContext().setAccessibleName("Find Dialog");        
        getAccessibleContext().setAccessibleDescription("Find dialog.");
        
        //设置的findPanel的布局为GridBagLayout        
        findPanel.setLayout(new java.awt.GridBagLayout());
        findLabel.setLabelFor(findField); //关联findLabel和findField        
        findLabel.setText("查找内容:"); //设置findLabel的标题
        
        // 添加findLabel到findPane1        
        findPanel.add(findLabel, new java.awt.GridBagConstraints());
        findLabel.getAccessibleContext().setAccessibleDescription("Find text.");
        
        //添加findField的动作监听器                
        findField.addActionListener(new java.awt.event.ActionListener(){
              public void actionPerformed(java.awt.event.ActionEvent evt){
                   findFieldActionPerformed(evt);
              }
        });
        
        gridBagConstraints = new java.awt.GridBagConstraints();        
        gridBagConstraints.fill = java.awt.GridBagConstraints.HORIZONTAL;        
        gridBagConstraints.weightx = 1.0;        
        gridBagConstraints.insets = new java.awt.Insets(0, 5, 0, 0);
        
        findPanel.add(findField, gridBagConstraints);
                
        findField.getAccessibleContext().setAccessibleName("Find Field");        
        findField.getAccessibleContext().setAccessibleDescription("Find field.");

        gridBagConstraints = new java.awt.GridBagConstraints();        
        gridBagConstraints.fill = java.awt.GridBagConstraints.BOTH;        
        gridBagConstraints.insets = new java.awt.Insets(11, 12, 0, 11);
        
        getContentPane().add(findPanel, gridBagConstraints);

        buttonPanel.setLayout(new java.awt.GridBagLayout());

        findButton.setMnemonic('f');        
        findButton.setText("查找");
        
        findButton.addActionListener(new java.awt.event.ActionListener(){
            public void actionPerformed(java.awt.event.ActionEvent evt){
               	findButtonActionPerformed(evt);
            }
        });

        buttonPanel.add(findButton, new java.awt.GridBagConstraints());

        closeButton.setMnemonic('c');        
        closeButton.setText("关闭");
        
        closeButton.addActionListener(new java.awt.event.ActionListener(){
             public void actionPerformed(java.awt.event.ActionEvent evt){
                 closeButtonActionPerformed(evt);
             }
        });

        gridBagConstraints = new java.awt.GridBagConstraints();        
        gridBagConstraints.insets = new java.awt.Insets(0, 5, 0, 0);        
        buttonPanel.add(closeButton, gridBagConstraints);

        gridBagConstraints = new java.awt.GridBagConstraints();        
        gridBagConstraints.gridx = 0;        
        gridBagConstraints.gridy = 1;        
        gridBagConstraints.anchor = java.awt.GridBagConstraints.SOUTHEAST;        
        gridBagConstraints.insets = new java.awt.Insets(17, 12, 11, 11);
        
        getContentPane().add(buttonPanel, gridBagConstraints);

    }//initComponents结束
       
 
     // 当文本框中输入回车键时，findFieldActionPerformed被调用,
     // 如果文本框中有文件，就调用Find button的响应方法，
     // 否则什么也不做；     
   
    private void  findFieldActionPerformed(java.awt.event.ActionEvent evt)
    {         	
        if (findField.getText().trim().length() > 0)
        {
           findButton.doClick();
        }
    }

     // 当find botton（查找按钮） 被按下的时候，调用此方法
     // 如果输入的字符在文件中能够找到，则定位于文件中该字
     // 符串出现的地方，否则什么也不做 
 
    private void findButtonActionPerformed(java.awt.event.ActionEvent evt)
    {               
    	
        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 
            {
                java.awt.Toolkit.getDefaultToolkit().beep();
            }
        }
    }
    

    // 当close button（关闭）被按下时，closeButtonActionPerformed方法被调用，
    // 它调用closeDialog方法，实现对话框的"关闭"
    
    private void closeButtonActionPerformed(java.awt.event.ActionEvent evt)
    {            
        closeDialog(null);
    }
    

    // 当对话框被关闭时，closeDialog法被调用，隐藏对话框  
     
    private void closeDialog(java.awt.event.WindowEvent evt) 
    {
        setVisible(false);
        
        dispose();
    }


    // 对话框类成员变量定义开始
    
    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;

}