GUI(练习-打开和保存文件)

野性酷女 2022-05-26 04:21 139阅读 0赞

/* 
    * 程序头部注释开始   
    * 程序的版权和版本声明部分   
    * Copyright (c) 2011, 烟台大学计算机学院学生   
    * All rights reserved.   
    * 文件名称：GUI(练习-打开和保存文件)                           
    * 作    者：薛广晨                               
    * 完成日期：2011  年 09 月  22  日   
    * 版 本号：x1.0            
       
    * 对任务及求解方法的描述部分   
    * 输入描述：  
    * 问题描述:    
    * 程序输出：   
    * 程序头部的注释结束 
    */
    
    package xue;
    import java.awt.*;
    import java.awt.event.*;
    import java.io.*;
    
    public class MyMenuTest {
    
    	/**
    	 * @param args
    	 */
    	private Frame f;
    	private MenuBar bar;
    	private TextArea ta;
    	private Menu fileMenu;
    	private MenuItem openItem, saveItem, closeItem;
    	
    	private FileDialog openDia, saveDia;
    	
    	private File file;
    	MyMenuTest()
    	{
    		init();
    	}
    	
    	
    	public void init() {
    		// TODO Auto-generated method stub
    		f = new Frame("my window");
    		f.setBounds(300, 100, 650, 600);
    		
    		bar = new MenuBar();
    		
    		ta = new TextArea();
    		
    		fileMenu = new Menu("文件");
    		
    		openItem = new MenuItem("打开");
    		saveItem = new MenuItem("保存");
    		closeItem = new MenuItem("退出");
    		
    		fileMenu.add(openItem);
    		fileMenu.add(saveItem);
    		fileMenu.add(closeItem);
    		bar.add(fileMenu);
    		
    		f.setMenuBar(bar);
    		
    		openDia = new FileDialog(f, "我要打开", FileDialog.LOAD);
    		saveDia = new FileDialog(f, "我要保存", FileDialog.SAVE);
    		
    		f.add(ta);
    		myEvent();
    		
    		f.setVisible(true);
    
    	}
    
    
    	private void myEvent() {
    		// TODO Auto-generated method stub
    		saveItem.addActionListener(new ActionListener()
    		{
    			public void actionPerformed(ActionEvent e)
    			{
    				if(file == null)
    				{
    					saveDia.setVisible(true);
    					
    					String dirPath = saveDia.getDirectory();
    					String fileName = saveDia.getFile();
    					
    					if(dirPath == null || fileName == null)
    					{
    						return;
    					}
    					file = new File(dirPath, fileName);	
    				}
    				
    				try
    				{
    					BufferedWriter bufw = new BufferedWriter(new FileWriter(file));
    					String text = ta.getText();
    					bufw.write(text);
    					bufw.flush();
    					bufw.close();
    				}
    				catch(IOException ex)
    				{
    					throw new RuntimeException();
    				}
    			}
    		});
    		
    		openItem.addActionListener(new ActionListener()
    		{
    			public void actionPerformed(ActionEvent e)
    			{
    				openDia.setVisible(true);
    				String dirPath = openDia.getDirectory();
    				String fileName = openDia.getFile();
    				
    				if(dirPath == null || fileName == null)
    				{
    					return;
    				}
    				
    				ta.setText("");
    				file = new File(dirPath, fileName);
    				
    				try
    				{
    					BufferedReader bufr = new BufferedReader(new FileReader(file));
    					String line = null;
    					
    					while((line = bufr.readLine()) != null)
    					{
    						ta.append(line + "\r\n");
    					}
    					bufr.close();
    				}
    				catch(IOException ex)
    				{
    					throw new RuntimeException("读取失败");
    				}
    			}
    		});
    		
    		closeItem.addActionListener(new ActionListener()
    		{
    
    			@Override
    			public void actionPerformed(ActionEvent e) {
    				// TODO Auto-generated method stub
    				System.exit(0);	
    			}
    		});
    		
    		f.addWindowListener(new WindowAdapter()
    		{
    			public void windowClosing(WindowEvent e)
    			{
    				System.exit(0);	
    			}
    		});
    	}
    
    
    	public static void main(String[] args) {
    		// TODO Auto-generated method stub
    		new MyMenuTest();
    
    	}
    
    }

运行结果：

![1348297300_8749.jpg][]

![1348297320_8192.jpg][]

上机感言：图形化界面好神奇啊，学了它才知道这么好玩

[1348297300_8749.jpg]: https://img-my.csdn.net/uploads/201209/22/1348297300_8749.jpg
[1348297320_8192.jpg]: https://img-my.csdn.net/uploads/201209/22/1348297320_8192.jpg