Getting compile error on ContentResolver.Insert() for creating event on Android platform

I am now trying to create an event for Android platform. I am using Xamarin Forms but writing platform specific code for creating event on Android.
I went through the docs http://developer.xamarin.com/guides/android/user_interface/calendar/

but I am getting the error "An object reference is required for the non-static field, method or property ... " for the following line.

ContentResolver.Insert(CalendarContract.Events.ContentUri, eventValues);

Any help will be greatly appreciated