Hi,
I've a window component with a Tree panel. The tree panel renders perfectly during the first time we open it. But once you close and re-open, the child nodes go missing.

Any pointers on where things could be going wrong?

Window Code below :
Code:
Ext.define('MyDesktop.view.MasterWindow', {
	extend: 'Ext.ux.desktop.Module',
	requires: [
	'Ext.tab.*',
	'Ext.window.*',
	'Ext.tip.*',
	'Ext.layout.container.Border',
	'Ext.data.ArrayStore',
	'Ext.util.Format',
	'Ext.grid.*',
	'Ext.grid.Panel',
	'Ext.grid.RowNumberer',
	'MyDesktop.store.MasterNavTree',
	],
	id:'master-win',
	init : function() {
		this.launcher = {
			text: 'Masters Management',
			iconCls:'icon-grid'
		};
	},
	createWindow : function() {
		var flag=0;
		var egtab = Ext.create('MyDesktop.view.employeegroup.EmpGroupTabPanel');
		var desigtab = Ext.create('MyDesktop.view.designation.DesigTabPanel');
		var jobtab = Ext.create('MyDesktop.view.jobtitle.JobTabPanel');
		var contentPanel = {
			id: 'content-panel',
			region: 'center', // this is what makes this panel into a region within the containing layout
			layout: 'card',
			margins: '2 5 5 0',
			activeItem: 0,
			border: false,
			items: [egtab,desigtab,jobtab]
		};


		var desktop = this.app.getDesktop();
		var masterwin = desktop.getWindow('master-win');
		if(!masterwin) {
			var masternavtree = Ext.create('MyDesktop.store.MasterNavTree');
			var navs = Ext.create('Ext.tree.Panel', {
		 		width: 200,
				border: false,
				store: masternavtree,
				rootVisible: true,
			   
				});
			masterwin = desktop.createWindow({
				id: 'master-win',
				title:'Master Management',
				iconCls: 'icon-grid',
				maximized: true,
				animCollapse:false,
				constrainHeader:true,
				closable: true,
				width: 600,
				minWidth: 600,
				height: 600,
				layout: {
					type: 'border',
					padding: 5
				},
				items: [{
					region: 'west',
					title: 'Navigation',
					split: true,
					rootVisible: true,
					autoScroll: true,
					items: [navs]
				},contentPanel]


			});
		}
		return masterwin;
	},
});
NavTree code
Code:
Ext.define('MyDesktop.store.MasterNavTree', {
    	extend:'Ext.data.TreeStore',
		alias:'data.mnavtree',
		root: {
        	expanded: true,
        	children: [
				{ id:'employeegroup', text: "Employee Group",  leaf:true, loaded:true },
{ id:'designation', text: "Designation", leaf: true },
{ id:'jobtitle', text: "Job Title", leaf: true } ] } });