JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://docs.sencha.com/ext-js/4-0/extjs/resources/css/ext-all.css">
<div id="events"></div>

CSS

.clear{
    clear:both;
}

#events{
    width: 200px;
    background:#fff;
    position:absolute;
    top: 0px;
    left: 290px;
}

JavaScript

Ext.define('NS.CustomView', {
    extend: 'Ext.DataView',
    itemTpl: ["<div>{label}</div>",
              "<p>MOUSE MOVE HERE. YOUR DIV IS HIDDEN :)</p>",
              "<div class='ph_horz_carousel' id='ph_horz_carousel_{#}' style='display:none'>",
                "<tpl for=\"subitems\">",
                    "<div class='ph_horz_item' id='horz_item_{#}' subitem_id='{#}'>",
                        "<img src='{inactive_img}' bsrc='{active_img}'/>",
                        "<span>{label}</span>",
                    "</div>",
                "</tpl>",
                "<div class='clear'></div>",
           "</div>",
           "<div class='clear'></div>"]
});

var ev = Ext.get('events');

var cv = Ext.create('NS.CustomView', {
    renderTo: Ext.getBody(),
    store: Ext.create('Ext.data.Store', {
        data: [{
            label: 'Movies',
            subitems:[{
                label: 'super',
                active_img: 'http://upload.wikimedia.org/wikipedia/commons/thumb/d/d5/CD_autolev_crop.jpg/220px-CD_autolev_crop.jpg',
                inactive_img: 'http://upload.wikimedia.org/wikipedia/commons/thumb/d/d5/CD_autolev_crop.jpg/220px-CD_autolev_crop.jpg',
                launch_info: {
                    type: 'url',
                    target: ''
                }
            }]
        }],
        /**
         * The css selector of the item to be interacted with
         */
        itemSelector: '.ph_horz_item',
        fields: ['label', 'subitems']
    }),
    listeners: {
        itemmouseenter: function() {
            alert('X');
            ev.createChild({html: 'x'});
        },
        itemmouseleave: function() {
            ev.createChild({html: 'leaving'});
        },
    }
});