helpframe.java

一个简单的文本编辑器,模趽msword写的哈!

package chapter14;
import java.awt.Container;//有段代码我不懂。！！！！！！！！！！
import java.awt.Cursor;
import java.io.File;
import java.io.IOException;
import java.net.MalformedURLException;
import java.net.URL;

import javax.swing.JEditorPane;
import javax.swing.JInternalFrame;
import javax.swing.JScrollPane;
import javax.swing.JViewport;
import javax.swing.SwingUtilities;
import javax.swing.event.HyperlinkEvent;
import javax.swing.event.HyperlinkListener;
import javax.swing.text.Document;

public class Helpframe extends JInternalFrame{
		public Helpframe(){
			super("help",true,true,true,true);
			this.setBounds(200,200,200,200);
			htmlpane html=new htmlpane();
			this.getContentPane().add(html);
		}
}
class htmlpane extends JScrollPane implements HyperlinkListener{
	    public JEditorPane html;
	    public htmlpane(){
	    	try{
	    		File f=new File("xiangfanyizhongshouye.html");
	    		String s=f.getAbsolutePath();
	    		s="file:"+s;
	    		URL url=new URL(s);
	    		html=new JEditorPane(s);
	    		html.setEditable(false);
	    		html.addHyperlinkListener(this);
	    		JViewport vp=this.getViewport();
	    		vp.add(html);//这两句为什么不能变成别的呢！
	    	}catch(MalformedURLException e){
	    		System.out.println("malformed url:"+e);
	    	}catch(IOException e){
	    		System.out.println("ioexception e:"+e);
	    	}
	    }
		public void hyperlinkUpdate(HyperlinkEvent e) {
		        if(e.getEventType()==HyperlinkEvent.EventType.ACTIVATED){
		        	linkactivated(e.getURL());
		        }
		}
	  protected void linkactivated(URL u){
		  Cursor c=html.getCursor();
		  Cursor waitcursor=Cursor.getPredefinedCursor(Cursor.WAIT_CURSOR);
		  html.setCursor(waitcursor);
		  SwingUtilities.invokeLater(new pageloader(u,c));
	  }
	class pageloader implements Runnable{
		URL url;
		Cursor cursor;
		pageloader(URL u,Cursor c){
			url=u;
			cursor=c;
		}
		public void run(){
			if(url==null){
				html.setCursor(cursor);
				Container parent=html.getParent();
				parent.repaint();
			}else{
				Document doc=html.getDocument();
				try{
					html.setPage(url);
				}catch(IOException e){
					html.setDocument(doc);
					getToolkit().beep();
				}finally{
					url=null;
					SwingUtilities.invokeLater(this);//这段程序我看不懂。
				}
			}
			
		}
	}
}