How to use

getNodeIcon

method

in

org.apache.wicket.extensions.markup.html.tree.DefaultAbstractTree

/**
 * @deprecated node icons should be created in {@link #newNodeIcon(MarkupContainer, String, TreeNode)}.
 */
@Override
@Deprecated
protected final ResourceReference getNodeIcon(TreeNode node) {
  return super.getNodeIcon(node);
}

@Override
protected Component newNodeIcon(final MarkupContainer parent, final String id, final TreeNode node) {
  ResourceReference nodeIcon = super.getNodeIcon(node);
  return HippoIcon.fromResource(id, nodeIcon);
}

  @Override
  protected void onComponentTag(ComponentTag tag)
  {
    super.onComponentTag(tag);
    tag.put("style", "background-image: url('" +
      RequestCycle.get().urlFor(getNodeIcon(node)) + "')");
  }
};

  /**
   * {@inheritDoc}
   */
  @Override
  protected void onComponentTag(final ComponentTag tag)
  {
    super.onComponentTag(tag);
    IRequestHandler handler = new ResourceReferenceRequestHandler(getNodeIcon(node));
    tag.put("style", "background-image: url('" + RequestCycle.get().urlFor(handler) +
      "')");
  }
};