Main.controller.js

sap.ui.define(['sap/ui/core/mvc/Controller', 'sap/m/MessageToast'],
   function(Controller, MessageToast) {
   "use strict";

   var CController = Controller.extend("NavExample.controller.Main", {

      handleNav: function(evt) {
         var navCon = this.getView().byId("navCon");
         var target = evt.getSource().data("target");
         if (target) {
            var animation = this.getView().byId("animationSelect").getSelectedKey();
            navCon.to(this.getView().byId(target), animation);
         } else {
            navCon.back();
         }
      },

      handlePainter: function() {
         var navCon = this.getView().byId("navCon");
         var page = navCon.getCurrentPage();
         console.log('page id', page.getId());
         var panel = page.getContent()[0];

         var painter = panel.getPainter();
         if (painter)
            MessageToast.show("Access painter for " + painter.GetClassName());

      }
   });


   return CController;

});