SetContentView for main page

In Xamarin.Android I can write:

SetContentView(Resource.Layout.Main);

for set the activity content from Main.axml

How I can do the same for Xamarin.Forms? How I can move data from Main.axml on main page?

Page page = App.GetMainPage();
page.SetContentView(Resource.Layout.Main); // page doesn't contain method SetContentView