Ext4 Form Panel combining static HTML with dynamic Ext components

HTML

<link rel="stylesheet" href="/js/lib/ext-4.0.2a/resources/css/ext-all.css">
<div id="form">
    <div>Custom Markup</div>
    <div id="text1" ></div>
    <div>Custom Markup</div>
    <div id="text2" ></div>
    <div>Custom Markup</div>
</div>

JavaScript

Ext.require(['Ext.layout.Layout'], function() {
        Ext.override(Ext.layout.Layout, {
            renderItem: function (item, target, position) {
                if(item.renderItemTo) {
                    // render 'renderItemTo' components into the specified DOM element
                    item.render(item.renderItemTo, 1);
                    // don't allow container layout to seize the component
                    item.layoutManagedHeight = 2;
                    item.layoutManagedWidth = 2;
                } else {
                    // just use standard Ext code for non-renderItemTo components
                    this.callOverridden(arguments);
                }
            },
            isValidParent: function(item, target, position) {
                // signal Ext that we are OK with were our 'renderItemTo' component is right now
                // otherwise it would get moved during the layout process
                return item.renderItemTo ? true : this.callOverridden(arguments);
            }
        });

    });

        Ext.onReady(function() {
            var panel = Ext.create('Ext.form.Panel', {
                contentEl: 'form',
                title: 'My FormPanel with special FX',
                items: [
                    {
                        xtype: 'textfield',
                        renderItemTo: 'text1',
                        fieldLabel: 'Label 1',
                    },
                    {
                        xtype: 'textfield',
                        renderItemTo: 'text2',
                        fieldLabel: 'Label 2'
                    }
                ]
            });

            Ext.create('Ext.window.Window', {
                width: 300,
                layout: 'fit',
                items: [
                    panel
                ]
            }).show();
            
            panel.add({xtype:'textfield',
            fieldLabel:'1123123123'})
        });