Merge branch 'ios-scrolltoposition' of https://github.com/adrianknight89/Xamarin.Forms into adrianknight89-ios-scrolltoposition

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla44461.cs

@@ -0,0 +1,49 @@
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+
+namespace Xamarin.Forms.Controls
+{
+	[Preserve(AllMembers = true)]
+	[Issue(IssueTracker.Bugzilla, 44461, "ScrollToPosition.Center works differently on Android and iOS", PlatformAffected.iOS)]
+	public class Bugzilla44461 : TestContentPage
+	{
+		protected override void Init()
+		{
+			var grid = new Grid
+			{
+				RowSpacing = 0,
+			};
+
+			var scrollView = new ScrollView
+			{
+				Orientation = ScrollOrientation.Horizontal,
+				VerticalOptions = LayoutOptions.Center,
+				BackgroundColor = Color.Yellow,
+				HeightRequest = 50
+			};
+			grid.Children.Add(scrollView);
+
+			var stackLayout = new StackLayout
+			{
+				Orientation = StackOrientation.Horizontal,
+				Spacing = 20
+			};
+
+			for (var i = 0; i < 10; i++)
+			{
+				var button = new Button
+				{
+					Text = "Button" + i
+				};
+				button.Clicked += (sender, args) =>
+				{
+					scrollView.ScrollToAsync(sender as Button, ScrollToPosition.Center, true);
+				};
+
+				stackLayout.Children.Add(button);
+			}
+			scrollView.Content = stackLayout;
+			Content = grid;
+		}
+	}
+}

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems

@@ -125,6 +125,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla42364.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla42519.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla43516.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Bugzilla44461.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)CarouselAsync.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla34561.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla34727.cs" />

Xamarin.Forms.Platform.iOS/Renderers/ScrollViewRenderer.cs

@@ -196,6 +196,10 @@ namespace Xamarin.Forms.Platform.iOS
 			else
 			{
 				var positionOnScroll = Controller.GetScrollPositionForElement(e.Element as VisualElement, e.Position);
+
+				positionOnScroll.X = positionOnScroll.X.Clamp(0, ContentSize.Width - Bounds.Size.Width);
+				positionOnScroll.Y = positionOnScroll.Y.Clamp(0, ContentSize.Height - Bounds.Size.Height);
+
 				switch (ScrollView.Orientation)
 				{
 					case ScrollOrientation.Horizontal: