CheckTreeCellRenderer.java

package net.sf.thingamablog.gui.app;

import java.awt.BorderLayout;
import java.awt.Component;

import javax.swing.JPanel;
import javax.swing.JTree;
import javax.swing.tree.TreeCellRenderer;
import javax.swing.tree.TreePath;

public class CheckTreeCellRenderer extends JPanel implements TreeCellRenderer{ 
    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private CheckTreeSelectionModel selectionModel; 
    private TreeCellRenderer delegate; 
    private TristateCheckBox checkBox = new TristateCheckBox(); 
 
    public CheckTreeCellRenderer(TreeCellRenderer delegate, CheckTreeSelectionModel selectionModel){ 
        this.delegate = delegate; 
        this.selectionModel = selectionModel; 
        setLayout(new BorderLayout()); 
        setOpaque(false); 
        checkBox.setOpaque(false); 
    } 
 
 
    public Component getTreeCellRendererComponent(JTree tree, Object value, boolean selected, boolean expanded, boolean leaf, int row, boolean hasFocus){ 
        Component renderer = delegate.getTreeCellRendererComponent(tree, value, selected, expanded, leaf, row, hasFocus); 
 
        TreePath path = tree.getPathForRow(row); 
        if(path!=null){ 
            if(selectionModel.isPathSelected(path, true))
                checkBox.setState(TristateCheckBox.SELECTED);
            else
                checkBox.setState(selectionModel.isPartiallySelected(path) ? TristateCheckBox.DONT_CARE : TristateCheckBox.NOT_SELECTED);
        } 
        removeAll(); 
        add(checkBox, BorderLayout.WEST); 
        add(renderer, BorderLayout.CENTER); 
        return this; 
    } 
}