How can I get absolute position of element/view in xamarin.forms

I am using Xamarin Forms version 1.2.2.0.

I have a Grid with 2 rows (1st row 50pixels height) in a Page, I have a Layout Control in 2nd row of Grid.

I am working on touch gestures. I am getting X & Y of touch positions relative to MainPage(using platform specific custom renderers).

I need either touch positions relative to the Layout Control or a method to find absolute position of that Layout Control Relative to MainPage.

(Layout Control here is a Custom AbsoluteLayout Control of Xamarin.Forms)

Thanks.