Ember - Preload page Not triggering for slow model

I am trying to add a preloading page for my slow model page. But my router not show the template for preload.

here is my structure of route:

http://localhost:4302/cs2i/purchase/purchaseDetails

this.route('cs2i', function() {

    this.route('purchase', function() {
      this.route('purchaseDetails', function(){
        this.route('loading'); //not loading I do have template
      });
      this.route('purchaseDetails-loading'); //not loading I do have template
    });
  });

what is the issue? how can i put a preloader to my route untill my data and template are rendered?

thanks in advance.

As well I do have a action with my 'purchase' page, which is triggeres even before data load.

actions: {

        loading : function( transition, originRoute ){

            console.log("loding done");//getting before data load

        },