= JTree =

== Populating Tree ==

<code java>
public class TestPane extends JPanel {

        private DefaultTreeModel model;
        private JTree tree;

        public TestPane() {
            setLayout(new BorderLayout());

            tree = new JTree();
            File rootFile = new File(".");
            DefaultMutableTreeNode root = new DefaultMutableTreeNode(rootFile);
            model = new DefaultTreeModel(root);

            tree.setModel(model);
            tree.setRootVisible(true);
            tree.setShowsRootHandles(true);

            add(new JScrollPane(tree));

            JButton load = new JButton("Load");
            add(load, BorderLayout.SOUTH);

            load.addActionListener(new ActionListener() {
                @Override
                public void actionPerformed(ActionEvent e) {

                    DefaultMutableTreeNode root = (DefaultMutableTreeNode) model.getRoot();
                    root.removeAllChildren();
                    model.reload();
                    File rootFile = (File) root.getUserObject();

                    addFiles(rootFile, model, root);

                    tree.expandPath(new TreePath(root));

                }
            });

        }

        protected void addFiles(File rootFile, DefaultTreeModel model, DefaultMutableTreeNode root) {

            for (File file : rootFile.listFiles()) {
                DefaultMutableTreeNode child = new DefaultMutableTreeNode(file);
                model.insertNodeInto(child, root, root.getChildCount());
                if (file.isDirectory()) {
                    addFiles(file, model, child);
                }
            }

        }
}        
</code>

Reference: [[https://stackoverflow.com/questions/15215578/how-to-build-a-jtree-dynamically]]        

== File List in Tree ==
<code java>
package com.ggl.testing;

import java.io.File;

import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.SwingUtilities;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;

public class FileBrowser implements Runnable {

    private DefaultMutableTreeNode root;

    private DefaultTreeModel treeModel;

    private JTree tree;

    @Override
    public void run() {
        JFrame frame = new JFrame("File Browser");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        File fileRoot = new File("C:/");
        root = new DefaultMutableTreeNode(new FileNode(fileRoot));
        treeModel = new DefaultTreeModel(root);

        tree = new JTree(treeModel);
        tree.setShowsRootHandles(true);
        JScrollPane scrollPane = new JScrollPane(tree);

        frame.add(scrollPane);
        frame.setLocationByPlatform(true);
        frame.setSize(640, 480);
        frame.setVisible(true);

        CreateChildNodes ccn = 
                new CreateChildNodes(fileRoot, root);
        new Thread(ccn).start();
    }

    public static void main(String[] args) {
        SwingUtilities.invokeLater(new FileBrowser());
    }

    public class CreateChildNodes implements Runnable {

        private DefaultMutableTreeNode root;

        private File fileRoot;

        public CreateChildNodes(File fileRoot, 
                DefaultMutableTreeNode root) {
            this.fileRoot = fileRoot;
            this.root = root;
        }

        @Override
        public void run() {
            createChildren(fileRoot, root);
        }

        private void createChildren(File fileRoot, 
                DefaultMutableTreeNode node) {
            File[] files = fileRoot.listFiles();
            if (files == null) return;

            for (File file : files) {
                DefaultMutableTreeNode childNode = 
                        new DefaultMutableTreeNode(new FileNode(file));
                node.add(childNode);
                if (file.isDirectory()) {
                    createChildren(file, childNode);
                }
            }
        }

    }

    public class FileNode {

        private File file;

        public FileNode(File file) {
            this.file = file;
        }

        @Override
        public String toString() {
            String name = file.getName();
            if (name.equals("")) {
                return file.getAbsolutePath();
            } else {
                return name;
            }
        }
    }

}
</code>

References: [[https://stackoverflow.com/questions/23804675/list-files-and-directories-with-jtree-and-file-in-java]]

== File List in JTree ==
<code java>
import java.io.File;
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import javax.swing.DefaultListModel;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;
//...

public class frmMain extends javax.swing.JFrame 
{
    public frmMain() 
    {
        initComponents();
        
        LaunchWebView();
        OpenXmlDataFile();
        
        try {
             treeFileList.setModel(new DefaultTreeModel(new DefaultMutableTreeNode("C:\\TEMP")));   // clear existing model
             FileUtils.scanAndLoadDirectory("C:\\TEMP", treeFileList);
        } catch (Exception exc) {
           // Do something
        }
    }

}    
</code>        

<code java>
package com.acme.myapp;

import java.io.File;
import javax.swing.JTree;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeModel;

public class FileUtils 
{
    public static void scanAndLoadDirectory(String location, JTree tree) throws InterruptedException 
    {    
        // Creates a file with the location filename
        //String location ="C:\\Users\\Ashish Padalkar\\Documents";
        File currentDir = new File(location);

        // Get root of tree model
        DefaultTreeModel modelTree = (DefaultTreeModel)tree.getModel();
        DefaultMutableTreeNode root = (DefaultMutableTreeNode) modelTree.getRoot();
        
        displayDirectoryContents(currentDir, modelTree, root);
    }
    
    public static void displayDirectoryContents(File dir, DefaultTreeModel model, DefaultMutableTreeNode curRoot) throws InterruptedException 
    {   
        File[] files = dir.listFiles();  // Creates array of file type for all the files found

        for (File file : files) {
            if (file == null) {
                System.out.println("NULL directory found");
                continue;
            }
            if (file.isDirectory()) {
                //---------------------------
                // File is a Directory
                //---------------------------
               if (file.listFiles() == null) {
                    // Skip null files
                    continue;
                }

                // Adds a new Directory node to tree root
                DefaultMutableTreeNode newdir = new DefaultMutableTreeNode(file.getName());
                curRoot.add(newdir);

                // Refresh the model to show changes
                model.reload();

                // Recursively calls the function again to explore the contents folder
                displayDirectoryContents(file, model, newdir);
                
            } else {  
                //---------------------------
                // File is not a directory
                //---------------------------
                // Inserts a node newfile under selected node which is the root
                DefaultMutableTreeNode selectednode = curRoot;
                DefaultMutableTreeNode newfile = new DefaultMutableTreeNode(file.getName());
                model.insertNodeInto(newfile, selectednode, selectednode.getChildCount());

                // Refresh the model to show the changes
                model.reload();
            }
        }    
    }
}
</code>