D+21 Text Editor(메모장 만들기)

2016. 09. 06. Tue. 스물한 번째 수업

오늘의 수업내용

• ActionListener를 이용해 메뉴 인식하기
• File Dialog를 이용해 File Open
• File Dialog를 이용해 File Save

예제(메모장 만들기)

package com.javalesson.ch20awt;
 
import java.awt.FileDialog;
import java.awt.Font;
import java.awt.Frame;
import java.awt.Menu;
import java.awt.MenuBar;
import java.awt.MenuItem;
import java.awt.TextArea;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.StringWriter;
 
class TextEditor extends Frame{
    TextArea ta;
    MenuBar mb;
    Menu menu;
    Menu menu1;
    Menu menu2;
    Menu menu3;
    Menu menu4;
    MenuItem miNew, miSaveAs, miOpen, miExit;
    String fileName;
    Font f1 = new Font("serif", Font.PLAIN, 20);
    public TextEditor(String title){
        super(title);
        ta = new TextArea();
        mb = new MenuBar();
        menu = new Menu("file");
        menu1 = new Menu("edit");
        menu2 = new Menu("form");
        menu3 = new Menu("view");
        menu4 = new Menu("help");
        miNew = new MenuItem("new");
        miSaveAs = new MenuItem("save");
        miOpen = new MenuItem("open");
        miExit = new MenuItem("exit");
        ActionListener mh = new MenuHandler();
        miNew.addActionListener(mh); 
        miSaveAs.addActionListener(mh); 
        miOpen.addActionListener(mh); 
        miExit.addActionListener(mh); 
 
        menu.add(miNew);
        menu.add(miOpen);
        menu.add(miSaveAs);
        menu.addSeparator();
        menu.add(miExit);
        mb.add(menu);
        mb.add(menu1);
        mb.add(menu2);
        mb.add(menu3);
        mb.add(menu4);
        this.setMenuBar(mb);
        this.add(ta);
        ta.setFont(f1);
        this.setBounds(550, 300, 500, 400);
        this.setVisible(true);
        this.addWindowListener(new WindowAdapter(){
                public void windowClosing(WindowEvent e) {
                e.getWindow().dispose();}
                });
    }
    public void fileOpen(String fileName) {//ch.17.L04SerialInput 참고
        this.fileName = fileName;
        FileReader fr;
        BufferedReader br=null;
        StringWriter sw; //sw.write(br.readline()); //ta.setText(sw);
        try{
            fr = new FileReader(fileName);
            br = new BufferedReader(fr);
            sw = new StringWriter();
            String line;
            while ((line = br.readLine()) != null) {
                sw.write(line+"\n");
            }//문제해결
            br.close();
            ta.setText(sw.toString());
        }catch(IOException e){e.printStackTrace();}
    }
    public void saveAs(String fileName){//ch.17.L04SerialOut 참고
        FileWriter fw;
        BufferedWriter bw;
        try{
            fw = new FileWriter(fileName);
            bw = new BufferedWriter(fw);
            bw.write(ta.getText());
            bw.close();
        }catch(IOException e){e.printStackTrace();}
    }
    class MenuHandler implements ActionListener{
        @Override
        public void actionPerformed(ActionEvent e) {
            String emd = e.getActionCommand();
            if(emd.equals("new")){
                ta.setText("");
            }else if(emd.equals("open")){
                FileDialog fd = new FileDialog(TextEditor.this, "file open");
                fd.setVisible(true);
                fileName = fd.getDirectory()+fd.getFile();
                
                    fileOpen(fileName);
                
            }else if(emd.equals("save")){
                FileDialog fd = new FileDialog(TextEditor.this, "save as", FileDialog.SAVE);
                fd.setVisible(true);
                fileName = fd.getDirectory()+fd.getFile();
                saveAs(fileName);
            }else if(emd.equals("exit")){
                System.exit(0);
            }
        }    
    }
}
 
public class L03TextEditor {
    public static void main(String[] args) {
        new TextEditor("메모장");
    }//main
}//class
 
 

※출력내용

오픈과 저장 기능을 넣으면서 메모장에 어떻게 구현되는지 이해할 수 있었던 수업이었다.