Answer by Yura Babiy for Xamarin.Forms: How to expand row from listview over full screen after tap or click?

For list view cell you could use a grid. Then binding width and height with a column definition. How to do it you can find on the internet. Screen width and height you can get in platform specific project. On android width you can get like that:

App.ScreenWidth = ( int )( Resources.DisplayMetrics.WidthPixels / Resources.DisplayMetrics.Density );

Something similar will be with height.