myfileguitest.java

记事本的部分代码 有打开保存 查询等功能

package com.last;

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

public class MyFileGUITest extends Frame implements ActionListener{

	/**
	 * @param args
	 */
	TextArea ta = new TextArea();
	MenuBar mb;
	Menu menu,edit;
	MenuItem open,save,find;
	MyFile mf = new MyFile(this);
	MyFindDialog mfd = new MyFindDialog(this,ta);
	
	public MyFileGUITest(){
		this.mb = new MenuBar();
		this.menu = new Menu("file");
		this.edit = new Menu("edit");
		this.open = new MenuItem("open");
		this.open.addActionListener(this);
		this.menu.add(open);
		
		this.save = new MenuItem("save");
		this.save.addActionListener(this);
		this.menu.add(save);
		
		this.find = new MenuItem("find");
		this.find.addActionListener(this);
		this.edit.add(find);
		this.mb.add(this.menu);
		this.mb.add(this.edit);
		this.setMenuBar(mb);
		//this.ta = new TextArea();
		this.add(this.ta);
		this.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				System.exit(0);
			}
		});
		this.setBounds(300,300,500,400);
		this.setVisible(true);
		
	}
	public static void main(String[] args) {
		new MyFileGUITest();

	}
	public void actionPerformed(ActionEvent e) {
		if(e.getSource() == open){
			this.ta.setText(this.mf.getData());
		}
		else if(e.getSource() == save){
			this.mf.setData(this.ta.getText());
		}
		else{
			this.mfd.showDialog();
			
		}
		
	}

}

class MyFile{
	FileDialog fd;
	
	public MyFile(Frame parent){
		this.fd = new FileDialog(parent,"open",FileDialog.LOAD);
	}
	
	public String getPath(){
		return this.fd.getDirectory() +"\\"+ this.fd.getFile();
	}
	
	public String getData(){
		this.fd.setMode(FileDialog.LOAD);
		//this.fd.setBounds(400,400,300,300);
		this.fd.setVisible(true);
		try {
			BufferedReader br = new BufferedReader(new FileReader(this.getPath()));
			String line = br.readLine();
			StringBuffer st = new StringBuffer(); 
			while(line != null){
				st.append(line +"\n");
				line = br.readLine();
			}
			br.close();
			return st.toString();
			
		} catch (Exception e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
			return null;
		}
	}
	
	public void setData(String data){
		this.fd.setMode(FileDialog.SAVE);
		this.fd.setVisible(true);
		
		try {
			PrintWriter pw = new PrintWriter(new FileWriter(this.getPath()));
			pw.write(data);
			pw.close();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
	}
}

class MyFindDialog extends Dialog implements ActionListener{
	
	Label lFind;
	TextField find;
	Button bFind;
	TextArea ta;
	
	public MyFindDialog(Frame owner, TextArea ta){
		super(owner,"find",false);
		this.ta = ta;
		this.setLayout(new FlowLayout());
		this.lFind = new Label("查找内容: ");
		this.find = new TextField(20);
		this.bFind = new Button("查找");
		this.bFind.addActionListener(this);
		this.add(this.lFind);
		this.add(this.find);
		this.add(this.bFind);
		
		
		this.addWindowListener(new WindowAdapter(){
			public void windowClosing(WindowEvent e){
				MyFindDialog.this.setVisible(false);
			}
		});
		
		
	}
	
	public void showDialog(){
		this.setBounds(400,400,400,150);
		this.setVisible(true);
	}
	
	public void find(){
		String text = this.ta.getText();
		String str = this.find.getText();
		
		int end = text.length();
		int len = str.length();
		
		int start = this.ta.getSelectionEnd();
		if(start == end){
			start = 0;
		}
		for( ; start<=end-len; start++){
			if(text.substring(start,start+len).equals(str)){
				this.ta.setSelectionStart(start);
				this.ta.setSelectionEnd(start+len);
				return;
			}
		}
		this.ta.setSelectionStart(end);
		this.ta.setSelectionEnd(end);
		
	}
	
	

	public void actionPerformed(ActionEvent e) {
		this.find();
		
	}
	
}