class TreePannel : DockPanel {
    void onMenuBar() {
        if (menuItem("Hey!"))  {
            print("clicked");
        }
    }

    void onRender() {
        Entity root = getRoot();
        
        treeNode(root.getName(), root.getId(), any(root),CallbackFunc(this.render));
    }

    void render(any@ data) {
        Entity entity;
        data.retrieve(entity);
        
        int childCount = entity.getChildCount();
        for (int i = 0; i < childCount; i++) {
            Entity child = entity.getChild(i);

            if (child.getChildCount() == 0) {
                treeNode(child.getName(), child.getId());
            } else {
                treeNode(child.getName(), child.getId(), any(child),CallbackFunc(this.render));
            }
            
        }
    }
}