AWT FileDialog類

介紹

FileDialog的控製是指一個對話窗口，用戶可以從中選擇一個文件。

類的聲明

以下是聲明為java.awt.FileDialog類：

public class FileDialog
   extends Dialog

字段域

以下java.awt.image類的字段：

static int LOAD -- 此常數的值指示文件對話框窗口的目的是找到要從中讀取數據的文件。
static int SAVE -- 這個常量值表示，這樣做的目的是要找到一個文件，寫文件對話框窗口。

類的構造函數

S.N.	構造函數& 說明
1	FileDialog(Dialog parent) Creates a file dialog for loading a file.
2	FileDialog(Dialog parent, String title) Creates a file dialog window with the specified title for loading a file.
3	FileDialog(Dialog parent, String title, int mode) Creates a file dialog window with the specified title for loading or saving a file.
4	FileDialog(Frame parent) Creates a file dialog for loading a file.
5	FileDialog(Frame parent, String title) Creates a file dialog window with the specified title for loading a file.
6	FileDialog(Frame parent, String title, int mode) Creates a file dialog window with the specified title for loading or saving a file.

類方法

S.N.	方法&說明
1	void addNotify() Creates the file dialog's peer.
2	String getDirectory() Gets the directory of this file dialog.
3	String getFile() Gets the selected file of this file dialog.
4	FilenameFilter getFilenameFilter() Determines this file dialog's filename filter.
5	int getMode() Indicates whether this file dialog box is for loading from a file or for saving to a file.
6	protected String paramString() Returns a string representing the state of this FileDialog window.
7	void setDirectory(String dir) Sets the directory of this file dialog window to be the specified directory.
8	void setFile(String file) Sets the selected file for this file dialog window to be the specified file.
9	void setFilenameFilter(FilenameFilter filter) Sets the filename filter for this file dialog window to the specified filter.
10	void setMode(int mode) Sets the mode of the file dialog.

繼承的方法

這個類繼承的方法從以下類：

java.awt.Dialog
java.awt.Window
java.awt.Component
java.lang.Object

Button 實例

選擇使用任何編輯器創建以下java程序D:/ > AWT > com > yiibai > gui >

AwtControlDemo

package com.yiibai.gui;

import java.awt.*;
import java.awt.event.*;

public class AwtControlDemo {

   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;

   public AwtControlDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AwtControlDemo  awtControlDemo = new AwtControlDemo();
      awtControlDemo.showFileDialogDemo();
   }

   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples - www.gitbook.net");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showFileDialogDemo(){
      headerLabel.setText("Control in action: FileDialog"); 

      final FileDialog fileDialog = new FileDialog(mainFrame,"Select file");
      Button showFileDialogButton = new Button("Open File");
      showFileDialogButton.addActionListener(new ActionListener() {
         @Override
         public void actionPerformed(ActionEvent e) {
            fileDialog.setVisible(true);
            statusLabel.setText("File Selected :" 
            + fileDialog.getDirectory() + fileDialog.getFile());
         }
      });

      controlPanel.add(showFileDialogButton);
      mainFrame.setVisible(true);  
   }
}

編譯程序，使用命令提示符。到 D:/ > AWT 然後鍵入以下命令。

D:AWT>javac comyiibaiguiAwtControlDemo.java

如果冇有錯誤出現，這意味著編譯成功。使用下麵的命令來運行程序。

D:AWT>java com.yiibai.gui.AwtControlDemo

驗證下麵的輸出