Solving "IllegalStateException: Components can be accessed only in event listeners" in zk 5.0.x

EventQueues.lookup("myQueue", EventQueues.APPLICATION, true).subscribe(
	new EventListener() {
		public void onEvent(Event evt) {
			if("onSomething".equals(evt.getName())) {
				// what to do with the event (maybe update your tree)
			}
		}
	}
});

EventQueues.lookup("myQueue", EventQueues.APPLICATION, true)
	.publish(new Event("onSomething", null, new SomeDataBean()));

<?page title="Display Tree" contentType="text/html;charset=UTF-8"?>
<zk>
	<window title="Tree with EventQueue" border="normal" 
		apply="samples.eventqueue.tree.TreeDisplayController">
		<tree id="tree" />
	</window>
</zk>

<?page title="Update Tree" contentType="text/html;charset=UTF-8"?>
<zk>
	<window border="normal">
		<hlayout>
			<textbox id="newNode" />
			<button label="Add Node">
				<attribute name="onClick"><![CDATA[
					// publish
					EventQueues.lookup("TreeDisplay", EventQueues.APPLICATION, true)
						.publish(new Event("AddNode", null, newNode.getValue()));
				]]></attribute>
			</button>
		</hlayout>
	</window>
</zk>

public class TreeDisplayController extends GenericForwardComposer {
	
	private Tree tree;
	private TreeModelA model;
	
	@Override
	public void doAfterCompose(Component comp) throws Exception {
		super.doAfterCompose(comp);
		
		tree.setTreeitemRenderer(new TreeitemRenderer() {
			@Override
			public void render(Treeitem item, Object data) throws Exception {
				Treerow r = new Treerow();
				Treecell c = new Treecell();
				item.appendChild(r);
				r.appendChild(c);
				c.appendChild(new Label(data instanceof List? "" : data.toString()));
			}
		});
		
		model = prepareTreeModel();
		tree.setModel(model);
		
		// subscribe
		EventQueues.lookup("TreeDisplay", EventQueues.APPLICATION, true)
				.subscribe(new EventListener() {
			public void onEvent(Event event) throws Exception {
				System.out.println("subscribe");
				if("AddNode".equals(event.getName())) {
					ArrayList parent = getRandomNode((ArrayList) model.getRoot());
					int position = (int) (Math.random() * parent.size());
					Object[] newNodes = {event.getData()};
					model.insert(parent, position, position, newNodes);
				}
			}
		});
	}
	
	private TreeModelA prepareTreeModel(){
		ArrayList mother = new ArrayList();
		
		//Create a branch "child1" and assign children to it
		ArrayList child1 = new ArrayList();
		child1.add("Tommy");
		child1.add("Juile");
		
		//Create a branch "child2" and assign children to it
		ArrayList child2 = new ArrayList();
		child2.add("Gray");
		
		//Create a branch "grandchild" and assign children to it
		ArrayList grandChild = new ArrayList();
		grandChild.add("Paul");
		grandChild.add("Eric");
		
		//Assign branch "grandchild" to be branch "child2"'s child
		child2.add(grandChild);
		
		//Assign branch "grand2" to be branch "child1"'s child
		child1.add(child2);
		
		//Assign children to root "mother"
		mother.add("Andy");
		mother.add("Davis");
		mother.add(child1);
		mother.add("Matter");
		mother.add("Kitty");
		
		return new TreeModelA(mother);
	}
	
	private ArrayList getRandomNode(ArrayList parent){
			if(Math.random() > 0.7) return parent;
			ArrayList nodeCache = new ArrayList();
			
			for(Object obj : parent)
				if(obj instanceof ArrayList) 
					nodeCache.add(obj);
			if(nodeCache.size() == 0) return parent;
			
			return getRandomNode((ArrayList)nodeCache.get(
					(int)(nodeCache.size() * Math.random())));
	}
}

public class TreeDisplayController extends GenericForwardComposer implements ModelListener {
	
	//All imports here

        Tree tree;
	EntropyTreeModel model;
	EntropyTreeitemRenderer treeRenderer;
	
	@Override
	public void doAfterCompose(Component comp) throws Exception {
		super.doAfterCompose(comp);
		
		treeRenderer = new EntropyTreeitemRenderer();
		tree.setTreeitemRenderer(treeRenderer);
		
		TreeFactory treeFactory = new TreeFactory();
		model = new EntropyTreeModel(treeFactory.computeJasmineTree(this));
		tree.setModel(model);
		
		tree.setWidth("100%");
		tree.setStyle("border:0px");
		EventListener el = new EventListener() {
			public void onEvent(Event arg0) throws Exception {
				onSelect();
			}
		};
		tree.addEventListener("onSelect", el);
		
		EventQueues.lookup("TreeDisplay", EventQueues.APPLICATION, true)
				.subscribe(new EventListener() {
			public void onEvent(Event event) throws Exception {
				//System.out.println("subscribe");
				if("AddNode".equals(event.getName())) {
					System.out.println("node added");
				}
			}
		});
	}
	
	public void setPageToDisplay(String page){
		//whatever, not relevant
	
	public void onSelect(){
		//whatever, not relevant
	}

	public void vmAdded(VMItem vm) {
		EventQueues.lookup("TreeDisplay", EventQueues.APPLICATION, true).publish(new Event("AddNode", null, vm));
	}
}

<button label="Add Node">
	<attribute name="onClick"><![CDATA[
		// publish
		EventQueues.lookup("TreeDisplay", EventQueues.APPLICATION, true)
			.publish(new Event("AddNode", null, newNode.getValue()));
	]]></attribute>
</button>