Ext.js Confirm Box

Ext.js Confirm Box

<!DOCTYPE html>
<html>
   <head>
      <link href = "https://cdnjs.cloudflare.com/ajax/libs/extjs/6.0.0/classic/theme-classic/resources/theme-classic-all.css"
         rel = "stylesheet" />
      <script type = "text/javascript"
         src = "https://cdnjs.cloudflare.com/ajax/libs/extjs/6.0.0/ext-all.js"></script>

      <script type = "text/javascript">
         Ext.onReady(function() {
            Ext.create('Ext.Button', {
               renderTo: Ext.getElementById('msgBox'),
               text: 'Click Me',
               listeners: {
                  click: function() {
                     Ext.MessageBox.confirm(
                        'Confirm', 'Are you sure you want to do this ?', callbackFunction);
                     function callbackFunction(btn) {
                        if(btn == 'yes') {
                           Ext.Msg.alert ('Button Click', 'You clicked the Yes button');
                        } else {
                           Ext.Msg.alert ('Button Click', 'You clicked the No button');
                        }
                     };
                  }
               }
            });
         });
      </script>
   </head>

   <body>
      <p> Click the button for alert box </p>
      <div id = "msgBox" ></div>
   </body>
</html>