ScrollView should account for Content margin (#392)

* ScrollView should account for Content margin

* Unit tests for content margin

4 files changed, 87 insertions, 2 deletions

diff --git a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla41418.cs b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla41418.cs
new file mode 100644
index 00000000..adda09ab
--- /dev/null
+++ b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla41418.cs
@@ -0,0 +1,30 @@
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+
+#if UITEST
+using Xamarin.UITest;
+using NUnit.Framework;
+#endif
+
+namespace Xamarin.Forms.Controls
+{
+	[Preserve(AllMembers = true)]
+	[Issue(IssueTracker.Bugzilla, 41418, "Margin inside ScrollView not working properly", PlatformAffected.All)]
+	public class Bugzilla41418 : TestContentPage
+	{
+		protected override void Init()
+		{
+			Content = new ScrollView()
+			{
+				BackgroundColor = Color.Yellow,
+				Content = new BoxView
+				{
+					Margin = 100,
+					WidthRequest = 500,
+					HeightRequest = 800,
+					BackgroundColor = Color.Red
+				}
+			};
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
index 07b8d7b4..0e1f0297 100644
--- a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
+++ b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
@@ -114,6 +114,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla41078.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla40998.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla41205.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Bugzilla41418.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla41424.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla42069.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla42069_Page.xaml.cs">
diff --git a/Xamarin.Forms.Core.UnitTests/ScrollViewUnitTests.cs b/Xamarin.Forms.Core.UnitTests/ScrollViewUnitTests.cs
index 066d4e5d..0ed525c0 100644
--- a/Xamarin.Forms.Core.UnitTests/ScrollViewUnitTests.cs
+++ b/Xamarin.Forms.Core.UnitTests/ScrollViewUnitTests.cs
@@ -399,5 +399,59 @@ namespace Xamarin.Forms.Core.UnitTests
 			Assert.That (scroll.ScrollX, Is.EqualTo (100));
 			Assert.That (scroll.ScrollY, Is.EqualTo (100));
 		}
+
+		[Test]
+		public void TestScrollContentMarginHorizontal()
+		{
+			View view = new View { IsPlatformEnabled = true, Margin = 100, WidthRequest = 100, HeightRequest = 100 };
+
+			var scroll = new ScrollView
+			{
+				Content = view,
+				Orientation = ScrollOrientation.Horizontal,
+				Platform = new UnitPlatform()
+			};
+			scroll.Layout(new Rectangle(0, 0, 100, 100));
+
+			Assert.AreEqual(new Size(300, 100), scroll.ContentSize);
+			Assert.AreEqual(100, scroll.Height);
+			Assert.AreEqual(100, scroll.Width);
+		}
+
+		[Test]
+		public void TestScrollContentMarginVertical()
+		{
+			View view = new View { IsPlatformEnabled = true, Margin = 100, WidthRequest = 100, HeightRequest = 100 };
+
+			var scroll = new ScrollView
+			{
+				Content = view,
+				Orientation = ScrollOrientation.Vertical,
+				Platform = new UnitPlatform()
+			};
+			scroll.Layout(new Rectangle(0, 0, 100, 100));
+
+			Assert.AreEqual(new Size(100, 300), scroll.ContentSize);
+			Assert.AreEqual(100, scroll.Height);
+			Assert.AreEqual(100, scroll.Width);
+		}
+
+		[Test]
+		public void TestScrollContentMarginBiDirectional()
+		{
+			View view = new View { IsPlatformEnabled = true, Margin = 100, WidthRequest = 100, HeightRequest = 100 };
+
+			var scroll = new ScrollView
+			{
+				Content = view,
+				Orientation = ScrollOrientation.Both,
+				Platform = new UnitPlatform()
+			};
+			scroll.Layout(new Rectangle(0, 0, 100, 100));
+
+			Assert.AreEqual(new Size(300, 300), scroll.ContentSize);
+			Assert.AreEqual(100, scroll.Height);
+			Assert.AreEqual(100, scroll.Width);
+		}
 	}
 }
diff --git a/Xamarin.Forms.Core/ScrollView.cs b/Xamarin.Forms.Core/ScrollView.cs
index 13ae6ad9..2c1f070d 100644
--- a/Xamarin.Forms.Core/ScrollView.cs
+++ b/Xamarin.Forms.Core/ScrollView.cs
@@ -268,7 +268,7 @@ namespace Xamarin.Forms
 
 		double GetMaxHeight(double height)
 		{
-			return Math.Max(height, _content.Bounds.Bottom + Padding.Bottom);
+			return Math.Max(height, _content.Bounds.Top + Padding.Top + _content.Bounds.Bottom + Padding.Bottom);
 		}
 
 		static double GetMaxHeight(double height, SizeRequest size)
@@ -278,7 +278,7 @@ namespace Xamarin.Forms
 
 		double GetMaxWidth(double width)
 		{
-			return Math.Max(width, _content.Bounds.Right + Padding.Right);
+			return Math.Max(width, _content.Bounds.Left + Padding.Left + _content.Bounds.Right + Padding.Right);
 		}
 
 		static double GetMaxWidth(double width, SizeRequest size)