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Why is IGGridView.Theme returning null after context switch?
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After updating our app to use Xamarin's Unified API and the recent SR release, I started getting object ref crashes with grid.Theme == null where previously it had been populated.  I tracked it down to the code below and was wondering if this is a defect or if you could explain the behavior.  I've got a workaround for the problem (setting the theme again inside the task) but I don't understand why the property is getting nulled to begin with.



        private IGGridView grid;


        private List<Section> CreateSections(CoreGraphics.CGRect bounds, UIView topView)
        {
            mainView = new UIView
            {
                Frame = new CoreGraphics.CGRect(0, 0, bounds.Width, bounds.Height),
                AutoresizingMask = UIViewAutoresizing.None,
                BackgroundColor = UIColor.Clear
            };

            grid = CreateGridView(gridFrame);
            grid.Theme = new PatientListGridTheme();  // custom Theme that inherits from IGGridViewThemeDefinition
            
            LoadGridData();        
            
            mainView.Add(grid);

            return new List<Section> { main };
        }

        
        private void LoadGridData()  // Invoked from UI thread
        {
            Console.WriteLine(string.Format("Theme : {0}", grid.Theme == null ? "NULL" : grid.Theme.GetType().ToString())); 

            //prints Theme : PatientListGridTheme

            Task.Run(async () =>
                {
                        await Task.Run(() =>
                        {
                            Console.WriteLine(string.Format("Theme : {0}", grid.Theme == null ? "NULL" : grid.Theme.GetType().ToString()));

                            //prints Theme : NULL !!!!!!!!


                            InvokeOnMainThread(() =>
                                {
                                    Console.WriteLine(string.Format("Theme : {0}", grid.Theme == null ? "NULL" : grid.Theme.GetType().ToString()));

                                    //prints Theme : NULL

                                    grid.Theme = new PatientListGridTheme();

                                    Console.WriteLine(string.Format("Theme : {0}", grid.Theme == null ? "NULL" : grid.Theme.GetType().ToString()));

                                    //prints Theme : PatientListGridTheme

                                });
                        }
                        );

                        InvokeOnMainThread(() => HideLoadingView());
                });
        }

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