以树结构显示文件目录

下面打算以树结构显示文件目录：

先来个热身吧，先实现下面的图像再说，回忆一下Jtree的用法。其实主要是我对swing不熟悉，哈哈。

代码如下：

package File;

import java.awt.FlowLayout;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTextArea;
import javax.swing.JTree;

public class TreeSimple extends JFrame{
	public TreeSimple(){
		JPanel panel = new JPanel();
		JTextArea area = new JTextArea(5, 30);
		JTree tree = new JTree();
		JScrollPane js1 = new JScrollPane(tree,
				JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
				JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
		panel.setLayout(new FlowLayout());
		JScrollPane js = new JScrollPane(area);
		JSplitPane jsplit = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, true,
				js1, js);
		panel.add(jsplit);
		setContentPane(panel);
		setSize(400, 400);
		setVisible(true);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}

	public static void main(String[] args){
		new TreeSimple();
	}
}

下面才是正式的

运行结果如下：

package File;

import java.awt.event.WindowAdapter;
import java.awt.event.WindowEvent;
import java.io.File;

import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreePath;

public class Disktree extends JFrame implements TreeSelectionListener{
	DefaultMutableTreeNode rootNode = new DefaultMutableTreeNode();
	JTree tree = new JTree(rootNode);
	JPanel panel = new JPanel();

	public Disktree(){
		tree.addTreeSelectionListener(this);
		JScrollPane js = new JScrollPane(tree,
				JScrollPane.VERTICAL_SCROLLBAR_ALWAYS,
				JScrollPane.HORIZONTAL_SCROLLBAR_ALWAYS);
		panel.add(tree);
		setContentPane(panel);

		addWindowListener(new WindowAdapter(){
			@Override
			public void windowActivated(WindowEvent e){
				File[] files = File.listRoots();
				for(File file : files){
					DefaultMutableTreeNode node = new DefaultMutableTreeNode(
							file);
					rootNode.add(node);
				}
				tree.expandPath(new TreePath(rootNode));
			}
		});

		setSize(500, 500);
		setVisible(true);
		setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
	}

	public static void main(String[] args){
		new Disktree();
	}

	@Override
	public void valueChanged(TreeSelectionEvent e){
		TreePath path = e.getPath();
		DefaultMutableTreeNode node = (DefaultMutableTreeNode) path
				.getLastPathComponent();

		Object userObject = node.getUserObject();
		if(!(userObject instanceof File)){
			return;
		}
		File folder = (File) userObject;
		if(!folder.isDirectory()){
			return;
		}
		File[] files = folder.listFiles();
		for(File file : files){
			node.add(new DefaultMutableTreeNode(file));
		}

	}
}