JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://cdn.kendostatic.com/2014.2.716/styles/kendo.common.min.css">
<link rel="stylesheet" href="http://cdn.kendostatic.com/2014.2.716/styles/kendo.rtl.min.css">
<link rel="stylesheet" href="http://cdn.kendostatic.com/2014.2.716/styles/kendo.default.min.css">
<link rel="stylesheet" href="http://cdn.kendostatic.com/2014.2.716/styles/kendo.dataviz.min.css">
<link rel="stylesheet" href="http://cdn.kendostatic.com/2014.2.716/styles/kendo.dataviz.default.min.css">
<link rel="stylesheet" href="http://cdn.kendostatic.com/2014.2.716/styles/kendo.mobile.all.min.css">
<script src="http://cdn.kendostatic.com/2014.2.716/js/kendo.all.min.js"></script>
 <div id="splitter">
  <div id="paneA">Pane A</div>
  <div id="paneB">Pane B</div>
</div>

<button id="getattr">Get value</button>

JavaScript

$("#splitter").kendoSplitter();
var splitter = $("#splitter").data("kendoSplitter");

$('#getattr').on('click', function() {
    //use jquery & target ids
    console.log($('#paneA').width(), $('#paneB').width());    

    //use jquery and get all panes info
    $('#splitter > .k-pane').each(function(id, item) {
       console.log( $(item).html(), $(item).width() ); 
    });
});