sencha framework problem after update 2.2 to 3.3.1

After ExtJS update 2.2 to 3.3.1 i have got a problem i can't solve.

I think its a TreePanel that is created. But there is no childNodes in "this"-object so:

ERROR: cs is null

renderChildren : function(suppressEvent){
    if(suppressEvent !== false){
   开发者_如何学Go     this.fireEvent('beforechildrenrendered', this);
    }
    var cs = this.childNodes;
    for(var i = 0, len = cs.length; i < len; i++){
        cs[i].render(true);
    }
    this.childrenRendered = true;
}, 

I can't figure out what is causing this problem, can't find who is calling this command.

---

this is probably window. Check that context (this) is set properly when the function is called (or event attached).

---

Found it in by looking in stack:

MapPanel.js (rad 77)

Code:

        var toc = new MyPanel.Toc( {
            map :map,
            border :false
        });
        tocPanel.add(toc);
        //toc.update(); //When i comment out these it works. 
        //tocPanel.doLayout();

"A TreePanel must have a root node before it is rendered." class=Ext.tree.TreePanel

Could it be this?