public void GridLayouterNotifyItemRangeMoved() { tlog.Debug(tag, $"GridLayouterNotifyItemRangeMoved"); var view = new CollectionView(new List <string>() { "123", "456" }) { Header = new RecyclerViewItem(), Footer = new RecyclerViewItem(), IsGrouped = true, }; Assert.IsNotNull(view, "Should not be null"); view.GroupFooterTemplate = new DataTemplate(typeof(RecyclerViewItem)); view.GroupHeaderTemplate = new DataTemplate(typeof(RecyclerViewItem)); view.ItemTemplate = new DataTemplate(typeof(RecyclerViewItem)); var gridLayouter = new GridLayouter(); Assert.IsNotNull(gridLayouter, "Should not be null"); gridLayouter.Initialize(view); gridLayouter.RequestLayout(100.0f); var source = new CustomGroupItemSource(view) { Position = 1, }; var orientationSize = gridLayouter.CalculateLayoutOrientationSize(); Assert.AreEqual(orientationSize, 6); var scrollPosition = gridLayouter.CalculateCandidateScrollPosition(0.0f); Assert.AreEqual(scrollPosition, 0.0f); gridLayouter.NotifyItemRangeInserted(source, 0, 10); gridLayouter.NotifyItemRangeMoved(source, 11, 16, 5); view.Dispose(); gridLayouter.Dispose(); source.Dispose(); tlog.Debug(tag, $"GridLayouterNotifyItemRangeMoved END (OK)"); }