<?xml version="1.0" encoding="UTF-8"?>

<zk xmlns="http://www.zkoss.org/2005/zul">
    When you click the "update" button, it should not show any error.
    <window title="Dynamically Change by Model">
        <zscript><![CDATA[
        class MySimpleTreeNode extends SimpleTreeNode {
                private String myData = null;
                public MySimpleTreeNode(String data, List children) {
                      super(data, children);
                      myData = data.toString();
                }
                 
                public String toString() {
                     return "Node: " + myData;
                }
                
                public void append(String data) {
                    myData = myData + data;
                }
                public Object getData() {
                    return myData;
                }
        }
        
       List aChildren = new ArrayList();
       List empty = new ArrayList();
       List a2Children = new ArrayList();
       MySimpleTreeNode a20 = new MySimpleTreeNode("A2-0", empty);
       MySimpleTreeNode a21 = new MySimpleTreeNode("A2-1", empty);
       MySimpleTreeNode a22 = new MySimpleTreeNode("A2-2", empty);
       a2Children.add(a20);
       a2Children.add(a21);
       a2Children.add(a22);
       
       MySimpleTreeNode a0 = new MySimpleTreeNode("A0", empty);
       MySimpleTreeNode a1 = new MySimpleTreeNode("A1", empty);
       MySimpleTreeNode a2 = new MySimpleTreeNode("A2", a2Children);
       aChildren.add(a0);
       aChildren.add(a1);
       aChildren.add(a2);
       
       List children = new ArrayList();
       MySimpleTreeNode a = new MySimpleTreeNode("A", aChildren);
       children.add(a);
       List bChildren = new ArrayList();
       MySimpleTreeNode b0 = new MySimpleTreeNode("B0", empty);
       MySimpleTreeNode b1 = new MySimpleTreeNode("B1", empty);
       MySimpleTreeNode b2 = new MySimpleTreeNode("B2", empty);
       bChildren.add(b0);
       bChildren.add(b1);
       bChildren.add(b2);
    	
       
    	
       MySimpleTreeNode b = new MySimpleTreeNode("B", bChildren);
       children.add(b);
       
       List rList = new ArrayList();
       rList.add(a);
       rList.add(b);
       MySimpleTreeNode r = new MySimpleTreeNode("Root", rList);
       
       List rootList = new ArrayList();
       rootList.add(r);
       MySimpleTreeNode root = new MySimpleTreeNode("Root", rootList);
       
       SimpleTreeModel stm = new SimpleTreeModel(root);
       
       
       public void update(){
       		r.append("a");
       		a0.append("0");
       		b0.append("0");
       		a22.append("2");
       		stm.fireEvent(root,0,0,org.zkoss.zul.event.TreeDataEvent.CONTENTS_CHANGED);
       		stm.fireEvent(a,0,0,org.zkoss.zul.event.TreeDataEvent.CONTENTS_CHANGED);
       		stm.fireEvent(b,0,0,org.zkoss.zul.event.TreeDataEvent.CONTENTS_CHANGED);
       		stm.fireEvent(a2,2,2,org.zkoss.zul.event.TreeDataEvent.CONTENTS_CHANGED);
       }
       
        ]]></zscript>
        
        <vbox>
            <tree model="${stm}" id="tree" width="700PX">
            </tree>
            <hbox>           
                <button label='update' onClick='update()' />
           </hbox>
        </vbox>
    </window>
    
</zk>