Merge pull request #39 from Redth/scrollbarvisibility

Add support for scrollbar visibility

Author: Redth

VirtualListView/Apple/VirtualListViewHandler.ios.maccatalyst.cs

@@ -232,6 +232,16 @@ void UpdateEmptyView()
 		}
 	}
 
+	void UpdateVerticalScrollbarVisibility(ScrollBarVisibility scrollBarVisibility)
+	{
+		PlatformView.ShowsVerticalScrollIndicator = scrollBarVisibility == ScrollBarVisibility.Always || scrollBarVisibility == ScrollBarVisibility.Default;
+	}
+	
+	void UpdateHorizontalScrollbarVisibility(ScrollBarVisibility scrollBarVisibility)
+	{
+		PlatformView.ShowsHorizontalScrollIndicator = scrollBarVisibility == ScrollBarVisibility.Always || scrollBarVisibility == ScrollBarVisibility.Default;
+	}
+
 	public void InvalidateData()
 	{
 		this.PlatformView.InvokeOnMainThread(() => {

VirtualListView/Controls/VirtualListView.cs

@@ -77,7 +77,25 @@ public VirtualListViewItemTemplateSelector ItemTemplateSelector
 	public static readonly BindableProperty ItemTemplateSelectorProperty =
 		BindableProperty.Create(nameof(ItemTemplateSelector), typeof(VirtualListViewItemTemplateSelector), typeof(VirtualListView), default);
 
+	
+	public ScrollBarVisibility VerticalScrollbarVisibility
+	{
+		get => (ScrollBarVisibility)GetValue(VerticalScrollbarVisibilityProperty);
+		set => SetValue(VerticalScrollbarVisibilityProperty, value);
+	}
+
+	public static readonly BindableProperty VerticalScrollbarVisibilityProperty =
+		BindableProperty.Create(nameof(VerticalScrollbarVisibility), typeof(ScrollBarVisibility), typeof(VirtualListView), ScrollBarVisibility.Default);
+
+
+	public ScrollBarVisibility HorizontalScrollbarVisibility
+	{
+		get => (ScrollBarVisibility)GetValue(HorizontalScrollbarVisibilityProperty);
+		set => SetValue(HorizontalScrollbarVisibilityProperty, value);
+	}
 
+	public static readonly BindableProperty HorizontalScrollbarVisibilityProperty =
+		BindableProperty.Create(nameof(HorizontalScrollbarVisibility), typeof(ScrollBarVisibility), typeof(VirtualListView), ScrollBarVisibility.Default);
 
 	public DataTemplate SectionHeaderTemplate
 	{

VirtualListView/IVirtualListView.cs

@@ -25,6 +25,10 @@ public interface IVirtualListView : IView
 	IList<ItemPosition> SelectedItems { get; set; }
 
 	ItemPosition? SelectedItem { get; set; }
+	
+	ScrollBarVisibility VerticalScrollbarVisibility { get; set; }
+	
+	ScrollBarVisibility HorizontalScrollbarVisibility { get; set; }
 
 	event EventHandler<SelectedItemsChangedEventArgs> OnSelectedItemsChanged;
 

VirtualListView/Platforms/Android/VirtualListViewHandler.android.cs

@@ -164,4 +164,35 @@ void UpdateEmptyView()
 			UpdateEmptyViewVisibility();
 		}
 	}
+	
+	ScrollBarVisibility _defaultHorizontalScrollVisibility = ScrollBarVisibility.Default;
+	ScrollBarVisibility _defaultVerticalScrollVisibility = ScrollBarVisibility.Default;
+
+	void UpdateVerticalScrollbarVisibility(ScrollBarVisibility scrollBarVisibility)
+	{
+		if (_defaultVerticalScrollVisibility == ScrollBarVisibility.Default)
+			_defaultVerticalScrollVisibility =
+				recyclerView.VerticalScrollBarEnabled ? ScrollBarVisibility.Always : ScrollBarVisibility.Never;
+
+		var newVerticalScrollVisiblility = scrollBarVisibility;
+
+		if (newVerticalScrollVisiblility == ScrollBarVisibility.Default)
+			newVerticalScrollVisiblility = _defaultVerticalScrollVisibility;
+
+		recyclerView.VerticalScrollBarEnabled = newVerticalScrollVisiblility == ScrollBarVisibility.Always;
+	}
+	
+	void UpdateHorizontalScrollbarVisibility(ScrollBarVisibility scrollBarVisibility)
+	{
+		if (_defaultHorizontalScrollVisibility == ScrollBarVisibility.Default)
+			_defaultHorizontalScrollVisibility =
+				recyclerView.HorizontalScrollBarEnabled ? ScrollBarVisibility.Always : ScrollBarVisibility.Never;
+
+		var newHorizontalScrollVisiblility = scrollBarVisibility;
+
+		if (newHorizontalScrollVisiblility == ScrollBarVisibility.Default)
+			newHorizontalScrollVisiblility = _defaultHorizontalScrollVisibility;
+
+		recyclerView.HorizontalScrollBarEnabled = newHorizontalScrollVisiblility == ScrollBarVisibility.Always;
+	}
 }

VirtualListView/Platforms/Windows/VirtualListViewHandler.windows.cs

@@ -4,6 +4,7 @@
 using WGrid = Microsoft.UI.Xaml.Controls.Grid;
 using WVisibility = Microsoft.UI.Xaml.Visibility;
 using WFrameworkElement = Microsoft.UI.Xaml.FrameworkElement;
+using WScrollBarVisibility = Microsoft.UI.Xaml.Controls.ScrollBarVisibility;
 using Microsoft.Maui.Platform;
 using Microsoft.UI.Xaml;
 
@@ -164,4 +165,26 @@ void UpdateEmptyView()
 
 		UpdateEmptyViewVisibility();
 	}
+
+	void UpdateVerticalScrollbarVisibility(ScrollBarVisibility scrollBarVisibility)
+	{
+		scrollViewer.VerticalScrollBarVisibility = scrollBarVisibility switch
+		{
+			ScrollBarVisibility.Default => WScrollBarVisibility.Auto,
+			ScrollBarVisibility.Always => WScrollBarVisibility.Visible,
+			ScrollBarVisibility.Never => WScrollBarVisibility.Hidden,
+			_ => WScrollBarVisibility.Auto
+		};
+	}
+
+	void UpdateHorizontalScrollbarVisibility(ScrollBarVisibility scrollBarVisibility)
+	{
+		scrollViewer.HorizontalScrollBarVisibility = scrollBarVisibility switch
+		{
+			ScrollBarVisibility.Default => WScrollBarVisibility.Auto,
+			ScrollBarVisibility.Always => WScrollBarVisibility.Visible,
+			ScrollBarVisibility.Never => WScrollBarVisibility.Hidden,
+			_ => WScrollBarVisibility.Auto
+		};
+	}
 }

VirtualListView/VirtualListViewHandler.cs

@@ -18,6 +18,8 @@ public partial class VirtualListViewHandler
 		[nameof(IVirtualListView.IsRefreshEnabled)] = MapIsRefreshEnabled,
 		[nameof(IVirtualListView.EmptyView)] = MapEmptyView,
 		[nameof(IVirtualListView.SelectedItems)] = MapSelectedItems,
+		[nameof(IVirtualListView.VerticalScrollbarVisibility)] = MapVerticalScrollbarVisibility,
+		[nameof(IVirtualListView.HorizontalScrollbarVisibility)] = MapHorizontalScrollbarVisibility,
 	};
 
 	public static CommandMapper<IVirtualListView, VirtualListViewHandler> CommandMapper = new(ViewCommandMapper)
@@ -135,5 +137,15 @@ public static void MapIsFooterVisible(VirtualListViewHandler handler, IVirtualLi
 	{
 		handler?.InvalidateData();
 	}
+	
+	public static void MapVerticalScrollbarVisibility(VirtualListViewHandler handler, IVirtualListView virtualListView)
+	{
+		handler?.UpdateVerticalScrollbarVisibility(virtualListView.VerticalScrollbarVisibility);
+	}
+	
+	public static void MapHorizontalScrollbarVisibility(VirtualListViewHandler handler, IVirtualListView virtualListView)
+	{
+		handler?.UpdateHorizontalScrollbarVisibility(virtualListView.HorizontalScrollbarVisibility);
+	}
 
 }