【发布时间】：2013-02-15 11:19:49
【问题描述】：
在我的项目中，我正在尝试添加一个文件资源管理器，以便用户可以从给定目录中选择文件。我想将此视图限制为项目的根文件夹（由用户确定）。这很像 Eclipses Package Explorer，因为“工作区”是由用户决定的。
目前文件不显示我想要的完整路径（来自 C:），但所有文件夹都显示完整路径（我不想要，我只想要文件夹名称）。
那么 JTree 是如何显示这些名称的呢？
我已经看到 JTree 使用 File.tostring() 方法，但是当我实现自己的文件并覆盖 toString 方法时，没有任何改变。
这是我的代码：
import java.awt.BorderLayout;
import java.io.File;
import javax.swing.JFileChooser;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeModelListener;
import javax.swing.tree.TreeModel;
import javax.swing.tree.TreePath;
import java.awt.Color;
import java.awt.Container;
import java.awt.Dimension;
import java.util.Collections;
import java.util.Vector;
import javax.swing.BoxLayout;
import javax.swing.JFrame;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.tree.DefaultMutableTreeNode;
public class pnl_fileView extends JPanel {
/**
* Display a file system in a JTree view
*
* @version $Id: FileTree.java,v 1.9 2004/02/23 03:39:22 ian Exp $
* @author Ian Darwin
*/
/** Construct a FileTree */
// public pnl_fileView(){
private myFile projectFile;
public pnl_fileView(myFile dir) {
//Create file explorer
//Need to add setup for root folder change.
//Config.getProject(); //This gets the current file from the config file.
//Begin choose File
if(projectFile == null){
JFileChooser chooser;
String choosertitle = "Please Choose a Root Folder";
chooser = new JFileChooser();
chooser.setCurrentDirectory(new java.io.File("."));
chooser.setDialogTitle(choosertitle);
chooser.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
//
// disable the "All files" option.
//
chooser.setAcceptAllFileFilterUsed(false);
//
if (chooser.showOpenDialog(this) == JFileChooser.APPROVE_OPTION) {
System.out.println("getCurrentDirectory(): " + chooser.getCurrentDirectory());
System.out.println("getSelectedFile() : " + chooser.getSelectedFile());
projectFile = new myFile(chooser.getSelectedFile().getAbsolutePath());
//projectFile = chooser.getSelectedFile();
}
else {
System.out.println("No Selection ");
}
}
else {
// Figure out where in the filesystem to start displaying
}
//End choose file
setLayout(new BorderLayout());
// Make a tree list with all the nodes, and make it a JTree
JTree tree = new JTree(addNodes(null, projectFile));
// Add a listener
tree.addTreeSelectionListener(new TreeSelectionListener() {
public void valueChanged(TreeSelectionEvent e) {
DefaultMutableTreeNode node = (DefaultMutableTreeNode) e
.getPath().getLastPathComponent();
System.out.println("You selected " + node);
}
});
// Lastly, put the JTree into a JScrollPane.
JScrollPane scrollpane = new JScrollPane();
scrollpane.getViewport().add(tree);
add(BorderLayout.CENTER, scrollpane);
}
/** Add nodes from under "dir" into curTop. Highly recursive. */
DefaultMutableTreeNode addNodes(DefaultMutableTreeNode curTop, myFile dir) {
String curPath = dir.getPath();
System.out.println(curPath);
DefaultMutableTreeNode curDir = new DefaultMutableTreeNode(curPath);
if (curTop != null) { // should only be null at root
curTop.add(curDir);
}
Vector<String> ol = new Vector<String>();
String[] tmp = dir.list();
for (int i = 0; i < tmp.length; i++)
ol.addElement(tmp[i]);
Collections.sort(ol, String.CASE_INSENSITIVE_ORDER);
myFile f;
Vector<String> files = new Vector<String>();
// Make two passes, one for Dirs and one for Files. This is #1.
for (int i = 0; i < ol.size(); i++) {
String thisObject = (String) ol.elementAt(i);
String newPath;
if (curPath.equals("."))
newPath = thisObject;
else
newPath = curPath + myFile.separator + thisObject;
System.out.println("this is the path: " + newPath);
if ((f = new myFile(newPath)).isDirectory())
addNodes(curDir, f);
else
files.addElement(thisObject);
}
// Pass two: for files.
for (int fnum = 0; fnum < files.size(); fnum++)
curDir.add(new DefaultMutableTreeNode(files.elementAt(fnum)));
return curDir;
}
public Dimension getMinimumSize() {
return new Dimension(200, 400);
}
public Dimension getPreferredSize() {
return new Dimension(200, 400);
}
/** Main: make a Frame, add a FileTree */
public static void main(String[] av) {
JFrame frame = new JFrame("FileTree");
frame.setForeground(Color.black);
frame.setBackground(Color.lightGray);
Container cp = frame.getContentPane();
if (av.length == 0) {
cp.add(new pnl_fileView(new myFile(".")));
} else {
cp.setLayout(new BoxLayout(cp, BoxLayout.X_AXIS));
for (int i = 0; i < av.length; i++)
cp.add(new pnl_fileView(new myFile(av[i])));
}
frame.pack();
frame.setVisible(true);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
}
class myFile extends File{
public myFile(String pathname) {
super(pathname);
}
public String toString() {
return "Hello World!";
}
public String getAbsolutePath(){
return "hi";
}
}
【问题讨论】：
-
视情况而定。
JTree将为每个节点使用Object#toString来确定它应该显示的内容。您应该创建自己的TreeCellRenderer，您可以使用它来确定显示相关对象的最佳方式。如果您能提供一个工作示例，它会更容易帮助您 -
添加了我的代码，我查看了 treeCellRenderer，但在使其正常工作时遇到了一些问题。代码的基础是从另一个来源获取的，所以还有一些片段我没有删除。
-
请学习java命名约定并遵守它们。