ExtJS 5 TreePanel data does not display?

Code:

var data = JSON.parse(JSON.stringify(contentConfig.treeData));
me.getMyTree().setRootNode(data);
me.getMyTree().setVisible(true);




Ext.define('MyTree', {
    extend: 'Ext.tree.Panel',
    alias: 'widget.myTree',
    padding: 0,
    margin: 0,


    hidden: true,


    width: 200,
    rootVisible: false,
    lines: false,


    store: Ext.create('MyTreeStore')
});


Ext.define('MyTreeStore', {
    extend: 'Ext.data.TreeStore',
    requires: ['MyTreeModel'],
    model: 'MyTreeModel'
});


Ext.define('MyTreeModel', {
    extend: 'Ext.data.TreeModel',
    proxy: {
        type: 'memory'
    },
    fields: [
        { name: 'id', type: 'string'},
        { name: 'text',  type: 'string', convert: function(v, rec) {
            return StringMessages.getMessage(v)
        }},
        { name: 'navConfig',  type: 'auto'}
    ]
});


treeRoot: {
    root: {
        expanded: true,
        children: [{
            text: 'common_configure', navConfig: {navId: 'configureSystem'}, iconCls: 'arrowTreeIcon', expanded: true,
            children: [
                { text: 'systemVMManagers', navConfig: {navId: 'vmManagers'}, iconCls: 'noTreeIcon', leaf: true},
                { text: 'common_hypervisorsAndStorage', navConfig: {navId: 'hypervisors'}, iconCls: 'noTreeIcon', leaf: true },
                { text: 'systemNetworks', navConfig: {navId: 'networks'}, iconCls: 'noTreeIcon', leaf: true},
                { text: 'systemNamingTemplates', navConfig: {navId: 'nameTemplates'}, iconCls: 'noTreeIcon', leaf: true}
            ]
        }, {
            text: 'systemUSXResources', navConfig: {navId: 'usxResources'}, iconCls: 'arrowTreeIcon', expanded: true,
                children: [
                    { text: 'systemUSXVMs', navConfig: {navId: 'usxServiceVMs'}, iconCls: 'noTreeIcon', leaf: true }
                ]
        }]
    }
}

ExtJS 5 TreePanel data does not display?