RelativeLayout scroll menu with animation at specific position

Hi guys

I want to create a scroll menu inside a RelativeLayout in XamarinForms.
The goal is to create a scrollable menu aligned to the left of the main screen, so that when you click on a menu item is automatically hidden and shown again when you click the button "show menu"

I have trouble aligning the menu to the left of the form and to hide the menu with animation

Now I get the Image Real.png and I want the Target.png

I send all the solution in VS2013 and the screens

Thanks