disabling the view of files in Jtree

[saurabh sood]

hi,
i was wondering if it is possible to display only the directories, exculding the files. that is it should look like the folders pane of windows explorer. if so how do we go about it.
thanks
saurabh sood
[ May 28, 2003: Message edited by: saurabh sood ]

[Nathan Pruett]

Are you asking about JTree or about JFileChooser?

If you are talking about JFileChooser (which I'll assume you mean since you are talking about files, and you'd have to customize JTree to deal with files. ) all you have to do is create a subclass of javax.swing.filechooser.FileFilter that implements the accept() method like this :

public boolean accept( File f ) {
return f.isDirectory();
}

then pass this file filter into the setFileFilter() method of the JFileChooser.

[saurabh sood]

hi,
thanks for replying. my real objective is to create a batch utility, that performs a set of tasks to all the files in that directory. the user selects the directory. i do know how to make only directory visible in JFileChooser.
that can be done by
JFileChooser jfc = new JFileChooser();
jfc.setFileSelectionMode(JFileChooser.DIRECTORIES_ONLY);
is it possible to display only directories in JTree
thanks in advance
saurabh sood

[Nathan Pruett]

To show directories in a JTree, you would do something like the following:

import java.awt.Component;
import java.io.File;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import javax.swing.event.TreeExpansionEvent;
import javax.swing.event.TreeWillExpandListener;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.DefaultTreeCellRenderer;
import javax.swing.tree.DefaultTreeModel;
public class DirectoryTree extends JFrame {
private JTree tree;
public DirectoryTree() {
super( "DirectoryTree" );
tree = new JTree( new DirectoryModel() );
tree.addTreeWillExpandListener( new DirectoryExpansionListener() );
tree.setCellRenderer( new DirectoryRenderer() );
getContentPane().add( new JScrollPane( tree ) );
setDefaultCloseOperation( EXIT_ON_CLOSE );
setBounds( 300, 300, 400, 400 );
setVisible( true );
}
public static void main(String[] args) {
new DirectoryTree();
}
private static class DirectoryModel extends DefaultTreeModel {
private DefaultMutableTreeNode root;
public DirectoryModel() {
super( new DefaultMutableTreeNode( "My Computer" ) );
root = (DefaultMutableTreeNode)getRoot();
File[] f = File.listRoots();
for ( int i = 0; i < f.length; i++ ) {
DefaultMutableTreeNode fileRoot = new DefaultMutableTreeNode( f[i] );
fileRoot.add( new DefaultMutableTreeNode() );
root.add( fileRoot );
}
}
}
private static class DirectoryRenderer extends DefaultTreeCellRenderer {
public Component getTreeCellRendererComponent( JTree tree, Object value,
boolean sel, boolean expanded, boolean leaf, int row,
boolean hasFocus ) {
JLabel l = (JLabel)super.getTreeCellRendererComponent( tree, value, sel,
expanded, leaf, row, hasFocus);
Object userObject = ((DefaultMutableTreeNode)value).getUserObject();
if ( userObject instanceof File ) {
String name = ((File)userObject).getName();
if ( name.trim().equals( "" ) ) {
l.setText( ((File)userObject).toString() );
}
else {
l.setText( ((File)userObject).getName() );
}
}
return l;
}
}
private static class DirectoryExpansionListener implements TreeWillExpandListener {
public void treeWillCollapse( TreeExpansionEvent e ) {
Object node = e.getPath().getLastPathComponent();
if ( node instanceof DefaultMutableTreeNode ) {
((DefaultMutableTreeNode)node).removeAllChildren();
((DefaultMutableTreeNode)node).add( new DefaultMutableTreeNode() );
}
}
public void treeWillExpand( TreeExpansionEvent e ) {
Object node = e.getPath().getLastPathComponent();
if ( node instanceof DefaultMutableTreeNode ) {
Object userObj = ((DefaultMutableTreeNode)node).getUserObject();
if ( userObj instanceof File ) {
((DefaultMutableTreeNode)node).removeAllChildren();
File f = (File)userObj;
try {
File[] childFile = f.listFiles();
for ( int i = 0; i < childFile.length; i++ ) {
if ( childFile[i].isDirectory() ) {
DefaultMutableTreeNode childNode = new DefaultMutableTreeNode( childFile[i] );
childNode.add( new DefaultMutableTreeNode() );
((DefaultMutableTreeNode)node).add( childNode );
}
}
}
catch ( Exception x ) {
// Problem reading directory...
x.printStackTrace();
}
}
}
}
}
}