Ajax Content Page loading content via ajax
Page contents can be loaded via ajax. To enable ajax content loading for the sidebar menu you can follow below steps:
 1. Add a DIV wrapper with page-content-body class under page-content DIV of the page content. 
 2. Apply ajaxify nav-link class to links of the sidebar menu and specify the content URL using href="some_ajax_content.php" link attribute. 
 3. Use Layout.loadAjaxContent('some_url.php') to load an ajax content programmatically 
 4. Use Layout.addAjaxContentSuccessCallback(function(res){ // res is ajax response object }) to add ajax success callback function 
Use Layout.addAjaxContentErrorCallback(function(res){ // res is ajax response object }) to add ajax error callback function