I need to display an arbitrary view with full descendants as an overlay covering the full screen.
I've approximated this at the Page level, where I set the Content to be an Absolute Layout that contains what would otherwise be set to the Page's Content property as its first child, using proportional sizing, to cover the full width and height of the page area. I display my overlay view as a second child, similarly positioned, which acts as a container for whatever view I want to display on the screen. I use Animation methods to animate the view's appearance and disappearance.
This works wholly using Forms with no custom renderers, which is desirable as this is a cross-platform app.
I am satisfied with the above implementation, except when a Navigation Page stack is involved or otherwise when the navigation bar is displayed. My overlay only covers the Page area, which does not include the navigation bar. This allows the user the interact with any buttons in the navigation bar while the overlay is displayed, which is not desirable, as the overlay is being used to display modal content which should be dismissed before interacting with other elements.
I would greatly appreciate any insights or suggestions.