treedemo.java

用ＪＡＶＡ 编写的一个菜单程序 实现了一些基本计算和信息的录入

import javax.swing.*;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.event.TreeSelectionListener;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.tree.TreeSelectionModel;
import java.awt.*;
import java.awt.event.*;
public class TreeDemo extends JFrame {
    String[][] data = {{"中国古典音乐","梁祝","高山流水","沧海一声笑","茉莉花"},
        			    {"外国古典音乐","yeah","i wanna love you","tomorrow once more"},
        				{"流行音乐","国内","国外","港台"},
        				{"歌手","亚瑟小子","古天乐","周杰伦"},
        			  };
   
    public TreeDemo() {
        super("音乐浏览");
        DefaultMutableTreeNode top = new DefaultMutableTreeNode("音乐");
        
        for( int i = 0; i<data.length; i++){
			top.add(createBranch(data[i]));
		}
        final JTree tree = new JTree(top);
        tree.getSelectionModel().setSelectionMode
                (TreeSelectionModel.SINGLE_TREE_SELECTION);
        tree.addTreeSelectionListener(new TreeSelectionListener() {
            public void valueChanged(TreeSelectionEvent e) {
                DefaultMutableTreeNode node = (DefaultMutableTreeNode)
                                   tree.getLastSelectedPathComponent();
                if (node == null) return;
                Object nodeInfo = node.getUserObject();              
                JOptionPane.showMessageDialog(null,nodeInfo.toString());
            }
               
         });
        JScrollPane treeView = new JScrollPane(tree);
        getContentPane().add(treeView, BorderLayout.CENTER);
    }
    DefaultMutableTreeNode createBranch(String[] data){
    	DefaultMutableTreeNode category = new DefaultMutableTreeNode(data[0]); 
        DefaultMutableTreeNode book = null;
        
        for( int i =1; i<data.length; i++){
        	book = new DefaultMutableTreeNode(data[i]); 
    		category.add(book);
    	}
    	
    	return category;
    }
    
    
}