code: function pageLoaded(args) {
      // Get the event sender
      var page = args.object;
      page.bindingContext = new main_view_model_1.HelloWorldModel(page);
      if (platform_1.isAndroid && platform_1.device.sdkVersion >= '21') {
          var window_1 = application_1.android.startActivity.getWindow();
          window_1.setStatusBarColor(new color_1.Color('#336699').android);
      }
  }
docs: Event handler for Page "loaded" event attached in main-page.xml