I have a page wherein I have a Grid and some controls, labels, pictures, etc. The user can tap the items on the page to get details, in which case I create a new instance of a custom control and add it to the Grid on top of everything else. When they dismiss the details, I remove it from the grid. This works 90% of the time but occasionally parts of the base page don't show up again when the detail control is dismissed.
I tried to fix this by simplifying the control hierarchy. I created a base grid with 1 column, 1 row and a child grid that has the primary page layout. The detail pages then go on the base grid, not in the same grid as primary page layout. Doing this means it works correctly more often but it still fails to repaint the base controls sometimes.
I think it's a Xamarin Forms bug. The app runs on iOS and this issue shows up in the Emulator and on my iPad.