JTree mit individuellen Icons

Ein einfaches Beispiel für einen JTree, bei welchem die Nodes individuelle Icons erhalten:

package com.sowas.icontree.javawiki;
 
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTree;
import java.awt.BorderLayout;
 
public class IconTreeDemo extends JFrame {
 
   public IconTreeDemo() {
      super("Icon Tree Demo");
      setDefaultCloseOperation(EXIT_ON_CLOSE);
 
      setLayout(new BorderLayout());
 
      ImageIcon iconRoot = new ImageIcon(getClass().getResource("images/iconRoot.png"));
      IconTreeNode root = new IconTreeNode(iconRoot, "Root");
      ImageIcon iconLeaf1 = new ImageIcon(getClass().getResource("images/iconLeaf1.png"));
      root.add(new IconTreeNode(iconLeaf1, "Leaf 1"));
      ImageIcon iconLeaf2 = new ImageIcon(getClass().getResource("images/iconLeaf2.png"));
      root.add(new IconTreeNode(iconLeaf2, "Leaf 2"));
      JTree tree = new JTree(root);
      tree.setCellRenderer(new IconTreeNodeRenderer());
 
      JScrollPane scrollPane = new JScrollPane(tree);
      getContentPane().add(scrollPane, BorderLayout.CENTER);
 
      setSize(400, 300);
      setLocationRelativeTo(null);
   }
 
   public static void main(String args[]) {
      IconTreeDemo ptd = new IconTreeDemo();
      ptd.setVisible(true);
   }
}

package com.sowas.icontree.javawiki;
 
import javax.swing.Icon;
import javax.swing.tree.DefaultMutableTreeNode;
 
public class IconTreeNode extends DefaultMutableTreeNode {
 
   public IconTreeNode(Icon icon, String text) {
      super(text);
      setUserObject(new TreeNodeData(icon, text));
   }
 
   class TreeNodeData {
 
      Icon icon;
      String text;
 
      public TreeNodeData(Icon icon, String text) {
         this.icon = icon;
         this.text = text;
      }
 
      public Icon getIcon() {
         return icon;
      }
 
      public void setIcon(Icon icon) {
         this.icon = icon;
      }
 
      public String getText() {
         return text;
      }
 
      public void setText(String text) {
         this.text = text;
      }
   }
}

package com.sowas.icontree.javawiki;
 
import javax.swing.JTree;
import javax.swing.tree.DefaultTreeCellRenderer;
import java.awt.Component;
 
public class IconTreeNodeRenderer extends DefaultTreeCellRenderer {
 
   public Component getTreeCellRendererComponent(JTree tree,
                                                 Object value,
                                                 boolean selected,
                                                 boolean expanded,
                                                 boolean leaf,
                                                 int row,
                                                 boolean hasFocus) {
      IconTreeNode.TreeNodeData data = (IconTreeNode.TreeNodeData) ((IconTreeNode) value).getUserObject();
      setIcon(data.getIcon());
      setText(data.getText());
      return this;
   }
}