reundo.java

java相关的j2me,j2se的一些相关资料

import java.awt.BorderLayout;
import java.awt.event.MouseEvent;
import java.awt.event.MouseListener;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JTextArea;
import javax.swing.UIManager;
import javax.swing.UnsupportedLookAndFeelException;
import javax.swing.event.UndoableEditEvent;
import javax.swing.event.UndoableEditListener;
import javax.swing.text.Document;
import javax.swing.undo.*;

public class ReUndo implements UndoableEditListener,MouseListener{
    
    public ReUndo() { }
    
    UndoManager undom = new UndoManager(); //
    UndoableEdit undoableEdit;             //
    JButton redo = new JButton("Redo");  //用于重做按钮
    JButton undo = new JButton("Undo");  //用于撤销按钮
    
    public static void main(String args[]){
        try {
            UIManager.setLookAndFeel(UIManager.getSystemLookAndFeelClassName());
        } catch (InstantiationException ex) { } 
          catch (IllegalAccessException ex) { } 
          catch (ClassNotFoundException ex) { } 
          catch (UnsupportedLookAndFeelException ex) { }
        
        ReUndo ru = new ReUndo();

        JFrame frame = new JFrame("RedoAndUndo");
        frame.setVisible(true);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setBounds(10,10,500,500);
        
        JTextArea area = new JTextArea();
        area.setVisible(true);
        Document doc = area.getDocument();  //取得一个文本容器
        doc.addUndoableEditListener(ru);  //为此文本容器添加可撤销操作监听
        
        JPanel p = new JPanel();
        p.setVisible(true);
        ru.redo.setSize(120,25);
        ru.redo.setVisible(true);
        ru.redo.addMouseListener(ru);
        ru.undo.setSize(120,25);
        ru.undo.setVisible(true);
        ru.undo.addMouseListener(ru);
        
        frame.add(area,BorderLayout.CENTER);
        frame.add(p,BorderLayout.SOUTH);
        p.add(ru.redo);
        p.add(ru.undo);
    }
    
    public void undoableEditHappened(UndoableEditEvent e) {
        undoableEdit = e.getEdit();     //取得每次操作的可撤销操作的数据
        undom.addEdit(undoableEdit);    //将数据存放到UndoManager中
    }
    
    public void mouseClicked(MouseEvent e) {
        if(e.getComponent() == redo){
            if(undom.canRedo()){undom.redo();} //判断此次能否能实现redo操作,是则执行.
            if(undom.canRedo() == false) {redo.setEnabled(false);} //判断下次能否能实现redo操作,否则使redo按钮不可用.
            if(undom.canUndo()){undo.setEnabled(true);} //判断undo操作是否能实现,是则使undo按钮可用.
        }else if(e.getComponent() == undo){
            if(undom.canUndo()){undom.undo();} //判断此次能否能实现undo操作,是则执行.
            if(undom.canUndo() == false){undo.setEnabled(false);}//判断下次能否能实现undo操作,否则使undo按钮不可用.
            if(undom.canRedo()){redo.setEnabled(true);}//判断redo操作是否能实现,是则使redo按钮可用
        }
    }    
    public void mousePressed(MouseEvent e) {
    }    
    public void mouseReleased(MouseEvent e) {
    }    
    public void mouseEntered(MouseEvent e) {
    }    
    public void mouseExited(MouseEvent e) {
    }    
}