Ionic 2 problems while reload page

when i change something in my ionic 2 app while it running on browser it take time and i only see blank page

i just wrote primary and it show me blank page


Welcome to Ionic!

This starter project comes with simple tabs-based layout for apps that are going to primarily use a Tabbed UI.

Take a look at the src/pages/ directory to add or change tabs, update any existing page or create new pages.