From 938a840e68bc6f1f26974ee8be0eb7a4ebcbeda2 Mon Sep 17 00:00:00 2001
From: Gerald Versluis <gerald.versluis@microsoft.com>
Date: Wed, 28 Aug 2019 13:25:02 +0200
Subject: [PATCH] Make Label display HTML from a string (#4527)

* Use UpdateText

* Added missing helper method and UI test

* Added missing helper for UWP

* Added csproj entry for helper

* Resolved rebase conflicts

* Update LabelRenderer.cs

* Update LabelRenderer.cs

* Update LabelRenderer.cs

* iOS Merge error fix

* Feedback

* - uwp fixes

* - android fix empty text

* - ios fix null and setting text when texttype starts as html

* - set _perfectSizeValid = false; after changed AttributedText

Setting the AttributedText causes GetDesiredSize to get called which sets _perfectSizeValid to true but at this point this frame still hasn't adjusted to any size change from *LayoutSubViews*. This resets _perfectSizeValid so after the AttributedText set the desiredsize can get pulled again

* Renamed PlainText to Text

* Fixed initial no HTML styling
---
 .../LabelTextType.cs                               |  88 ++++++++++++++++
 .../Xamarin.Forms.Controls.Issues.Shared.projitems |   1 +
 .../CoreGalleryPages/LabelCoreGalleryPage.cs       |  37 +++++++
 Xamarin.Forms.Core/Label.cs                        |   9 ++
 Xamarin.Forms.Core/TextType.cs                     |   8 ++
 Xamarin.Forms.CustomAttributes/TestAttributes.cs   |   3 +-
 .../FastRenderers/LabelRenderer.cs                 |  24 ++++-
 Xamarin.Forms.Platform.Android/Forms.cs            |  11 ++
 .../Renderers/LabelRenderer.cs                     |  26 ++++-
 Xamarin.Forms.Platform.UAP/LabelHtmlHelper.cs      | 112 +++++++++++++++++++++
 Xamarin.Forms.Platform.UAP/LabelRenderer.cs        |  46 +++++++--
 .../Xamarin.Forms.Platform.UAP.csproj              |   1 +
 .../Renderers/LabelRenderer.cs                     |  66 +++++++++++-
 13 files changed, 414 insertions(+), 18 deletions(-)
 create mode 100644 Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/LabelTextType.cs
 create mode 100644 Xamarin.Forms.Core/TextType.cs
 create mode 100644 Xamarin.Forms.Platform.UAP/LabelHtmlHelper.cs

diff --git a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/LabelTextType.cs b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/LabelTextType.cs
new file mode 100644
index 0000000..3590c08
--- /dev/null
+++ b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/LabelTextType.cs
@@ -0,0 +1,88 @@
+using System;
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+
+#if UITEST
+using Xamarin.Forms.Core.UITests;
+using Xamarin.UITest;
+using NUnit.Framework;
+using System.Linq;
+#endif
+
+namespace Xamarin.Forms.Controls.Issues
+{
+#if UITEST
+	[Category(UITestCategories.Label)]
+#endif
+	[Preserve(AllMembers = true)]
+	[Issue(IssueTracker.None, 0, "Implementation of Label TextType", PlatformAffected.All)]
+	public class LabelTextType : TestContentPage
+	{
+		protected override void Init()
+		{
+			var label = new Label
+			{
+				AutomationId = "TextTypeLabel",
+				Text = "<h1>Hello World!</h1>"
+			};
+
+			var button = new Button
+			{
+				AutomationId = "ToggleTextTypeButton",
+				Text = "Toggle HTML/Plain"
+			};
+
+			button.Clicked += (s, a) =>
+			{
+				label.TextType = label.TextType == TextType.Html ? TextType.Text : TextType.Html;
+			};
+
+
+			Label htmlLabel = new Label() { TextType = TextType.Html };
+			Label normalLabel = new Label();
+			Label nullLabel = new Label() { TextType = TextType.Html };
+
+			Button toggle = new Button()
+			{
+				Text = "Toggle some more things",
+				Command = new Command(() =>
+				{
+					htmlLabel.Text = $"<b>{DateTime.UtcNow}</b>";
+					normalLabel.Text = $"<b>{DateTime.UtcNow}</b>";
+
+					if (String.IsNullOrWhiteSpace(nullLabel.Text))
+						nullLabel.Text = "hi there";
+					else
+						nullLabel.Text = null;
+				})
+			};
+
+
+			var stacklayout = new StackLayout();
+			stacklayout.Children.Add(label);
+			stacklayout.Children.Add(button);
+			stacklayout.Children.Add(htmlLabel);
+			stacklayout.Children.Add(normalLabel);
+			stacklayout.Children.Add(nullLabel);
+			stacklayout.Children.Add(toggle);
+
+			Content = stacklayout;
+		}
+
+#if UITEST
+		[Test]
+		public void LabelToggleHtmlAndPlainTextTest() 
+		{
+			RunningApp.WaitForElement ("TextTypeLabel");
+			RunningApp.Screenshot ("I see plain text");
+
+			Assert.IsTrue(RunningApp.Query("TextTypeLabel").FirstOrDefault()?.Text == "<h1>Hello World!</h1>");
+
+			RunningApp.Tap("ToggleTextTypeButton");
+			RunningApp.Screenshot ("I see HTML text");
+
+			Assert.IsFalse(RunningApp.Query("TextTypeLabel").FirstOrDefault()?.Text.Contains("<h1>") ?? true);
+		}
+#endif
+	}
+}
diff --git a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
index 1711c8f..2fb5d14 100644
--- a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
+++ b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Xamarin.Forms.Controls.Issues.Shared.projitems
@@ -1029,6 +1029,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Issue6738.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)GitHub6926.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue5503.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)LabelTextType.cs" />
   </ItemGroup>
   <ItemGroup>
     <EmbeddedResource Include="$(MSBuildThisFileDirectory)Bugzilla22229.xaml">
diff --git a/Xamarin.Forms.Controls/CoreGalleryPages/LabelCoreGalleryPage.cs b/Xamarin.Forms.Controls/CoreGalleryPages/LabelCoreGalleryPage.cs
index e7d0c67..9d7bbeb 100644
--- a/Xamarin.Forms.Controls/CoreGalleryPages/LabelCoreGalleryPage.cs
+++ b/Xamarin.Forms.Controls/CoreGalleryPages/LabelCoreGalleryPage.cs
@@ -236,6 +236,40 @@ namespace Xamarin.Forms.Controls
 					Padding = new Thickness(40, 20)
 				}
 			);
+			
+			var htmlLabelContainer = new ViewContainer<Label>(Test.Label.TextType,
+				new Label
+				{
+					Text = "<h1>Hello world!</h1>",
+					TextType = TextType.Html
+				});
+
+			var htmlLabelMultipleLinesContainer = new ViewContainer<Label>(Test.Label.TextType,
+				new Label
+				{
+					Text = "<h1>Hello world!</h1><p>Lorem <strong>ipsum</strong> bla di bla <i>blabla</i> blablabl&nbsp;ablabla & blablablablabl ablabl ablablabl ablablabla blablablablablablab lablablabla blablab lablablabla blablabl ablablablab lablabla blab lablablabla blablab lablabla blablablablab lablabla blablab lablablabl ablablabla blablablablablabla blablabla</p>",
+					TextType = TextType.Html,
+					MaxLines = 3
+				});
+
+			var toggleLabel = new Label
+			{
+				TextType = TextType.Html,
+				Text = "<h1 style=\"color: red;\">Hello world!</h1><p>Lorem <strong>ipsum</strong></p>"
+				
+			};
+
+			var gestureRecognizer = new TapGestureRecognizer();
+
+			gestureRecognizer.Tapped += (s, a) =>
+			{
+				toggleLabel.TextType = toggleLabel.TextType == TextType.Html ? TextType.Text : TextType.Html;
+			};
+
+			toggleLabel.GestureRecognizers.Add(gestureRecognizer);
+
+			var toggleHtmlPlainTextLabelContainer = new ViewContainer<Label>(Test.Label.TextType,
+				toggleLabel);
 
 			Add (namedSizeMediumBoldContainer);
 			Add (namedSizeMediumItalicContainer);
@@ -272,6 +306,9 @@ namespace Xamarin.Forms.Controls
 			Add (maxlinesTailTruncContainer);
 			Add (maxlinesWordWrapContainer);
 			Add(paddingContainer);
+			Add (htmlLabelContainer);
+			Add (htmlLabelMultipleLinesContainer);
+			Add (toggleHtmlPlainTextLabelContainer);
 		}
 	}
 }
\ No newline at end of file
diff --git a/Xamarin.Forms.Core/Label.cs b/Xamarin.Forms.Core/Label.cs
index 7210624..9126181 100644
--- a/Xamarin.Forms.Core/Label.cs
+++ b/Xamarin.Forms.Core/Label.cs
@@ -89,6 +89,9 @@ namespace Xamarin.Forms
 			});
 
 		public static readonly BindableProperty PaddingProperty = PaddingElement.PaddingProperty;
+		
+		public static readonly BindableProperty TextTypeProperty = BindableProperty.Create(nameof(TextType), typeof(TextType), typeof(Label), TextType.Text,
+			propertyChanged: (bindable, oldvalue, newvalue) => ((Label)bindable).InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged));
 
 		readonly Lazy<PlatformConfigurationRegistry<Label>> _platformConfigurationRegistry;
 
@@ -212,6 +215,12 @@ namespace Xamarin.Forms
 			get { return (Thickness)GetValue(PaddingProperty); }
 			set { SetValue(PaddingProperty, value); }
 		}
+		
+		public TextType TextType
+		{
+			get => (TextType)GetValue(TextTypeProperty);
+			set => SetValue(TextTypeProperty, value);
+		}
 
 		double IFontElement.FontSizeDefaultValueCreator() =>
 			Device.GetNamedSize(NamedSize.Default, (Label)this);
diff --git a/Xamarin.Forms.Core/TextType.cs b/Xamarin.Forms.Core/TextType.cs
new file mode 100644
index 0000000..bbe0cf9
--- /dev/null
+++ b/Xamarin.Forms.Core/TextType.cs
@@ -0,0 +1,8 @@
+namespace Xamarin.Forms
+{
+	public enum TextType
+	{
+		Text,
+		Html
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.Forms.CustomAttributes/TestAttributes.cs b/Xamarin.Forms.CustomAttributes/TestAttributes.cs
index 4ebeefa..8cf97b9 100644
--- a/Xamarin.Forms.CustomAttributes/TestAttributes.cs
+++ b/Xamarin.Forms.CustomAttributes/TestAttributes.cs
@@ -635,7 +635,8 @@ namespace Xamarin.Forms.CustomAttributes
 			VerticalTextAlignmentStart,
 			VerticalTextAlignmentCenter,
 			VerticalTextAlignmentEnd,
-			MaxLines
+			MaxLines,
+			TextType
 		}
 
 		public enum MasterDetailPage
diff --git a/Xamarin.Forms.Platform.Android/FastRenderers/LabelRenderer.cs b/Xamarin.Forms.Platform.Android/FastRenderers/LabelRenderer.cs
index 7da8f9b..eadd780 100644
--- a/Xamarin.Forms.Platform.Android/FastRenderers/LabelRenderer.cs
+++ b/Xamarin.Forms.Platform.Android/FastRenderers/LabelRenderer.cs
@@ -251,6 +251,7 @@ namespace Xamarin.Forms.Platform.Android.FastRenderers
 					UpdateGravity();
 				if (e.OldElement?.MaxLines != e.NewElement.MaxLines)
 					UpdateMaxLines();
+
 				UpdatePadding();
 
 				ElevationHelper.SetElevation(this, e.NewElement);
@@ -263,7 +264,8 @@ namespace Xamarin.Forms.Platform.Android.FastRenderers
 
 			if (e.PropertyName == Label.HorizontalTextAlignmentProperty.PropertyName || e.PropertyName == Label.VerticalTextAlignmentProperty.PropertyName)
 				UpdateGravity();
-			else if (e.PropertyName == Label.TextColorProperty.PropertyName)
+			else if (e.PropertyName == Label.TextColorProperty.PropertyName ||
+				e.PropertyName == Label.TextTypeProperty.PropertyName)
 				UpdateText();
 			else if (e.PropertyName == Label.FontProperty.PropertyName)
 				UpdateText();
@@ -380,7 +382,23 @@ namespace Xamarin.Forms.Platform.Android.FastRenderers
 					SetTextColor(_labelTextColorDefault);
 					_lastUpdateColor = Color.Default;
 				}
-				Text = Element.Text;
+
+				switch (Element.TextType)
+				{
+					case TextType.Html:
+						if (Forms.IsNougatOrNewer)
+							Control.SetText(Html.FromHtml(Element.Text ?? string.Empty, FromHtmlOptions.ModeCompact), BufferType.Spannable);
+						else
+#pragma warning disable CS0618 // Type or member is obsolete
+							Control.SetText(Html.FromHtml(Element.Text ?? string.Empty), BufferType.Spannable);
+#pragma warning restore CS0618 // Type or member is obsolete
+						break;
+
+					default:
+						Text = Element.Text;
+						break;
+				}
+				
 				UpdateColor();
 				UpdateFont();
 
@@ -416,4 +434,4 @@ namespace Xamarin.Forms.Platform.Android.FastRenderers
 			_lastSizeRequest = null;
 		}
 	}
-}
+}
\ No newline at end of file
diff --git a/Xamarin.Forms.Platform.Android/Forms.cs b/Xamarin.Forms.Platform.Android/Forms.cs
index 20ca905..52a721c 100644
--- a/Xamarin.Forms.Platform.Android/Forms.cs
+++ b/Xamarin.Forms.Platform.Android/Forms.cs
@@ -56,6 +56,7 @@ namespace Xamarin.Forms
 		static BuildVersionCodes? s_sdkInt;
 		static bool? s_isLollipopOrNewer;
 		static bool? s_isMarshmallowOrNewer;
+		static bool? s_isNougatOrNewer;
 
 		[Obsolete("Context is obsolete as of version 2.5. Please use a local context instead.")]
 		[EditorBrowsable(EditorBrowsableState.Never)]
@@ -98,6 +99,16 @@ namespace Xamarin.Forms
 			}
 		}
 
+		internal static bool IsNougatOrNewer
+		{
+			get
+			{
+				if (!s_isNougatOrNewer.HasValue)
+					s_isNougatOrNewer = (int)Build.VERSION.SdkInt >= 24;
+				return s_isNougatOrNewer.Value;
+			}
+		}
+
 		public static float GetFontSizeNormal(Context context)
 		{
 			float size = 50;
diff --git a/Xamarin.Forms.Platform.Android/Renderers/LabelRenderer.cs b/Xamarin.Forms.Platform.Android/Renderers/LabelRenderer.cs
index 2771697..d808ccc 100644
--- a/Xamarin.Forms.Platform.Android/Renderers/LabelRenderer.cs
+++ b/Xamarin.Forms.Platform.Android/Renderers/LabelRenderer.cs
@@ -135,7 +135,6 @@ namespace Xamarin.Forms.Platform.Android
 					UpdateMaxLines();
 				if (e.OldElement.CharacterSpacing != e.NewElement.CharacterSpacing)
 					UpdateCharacterSpacing();
-
 			}
 			UpdateTextDecorations();
 			UpdatePadding();
@@ -158,13 +157,13 @@ namespace Xamarin.Forms.Platform.Android
 				UpdateLineBreakMode();
 			else if (e.PropertyName == Label.TextDecorationsProperty.PropertyName)
 				UpdateTextDecorations();
-			else if (e.PropertyName == Label.TextProperty.PropertyName || e.PropertyName == Label.FormattedTextProperty.PropertyName)
+			else if (e.IsOneOf(Label.TextProperty, Label.FormattedTextProperty, Label.TextTypeProperty))
 				UpdateText();
 			else if (e.PropertyName == Label.LineHeightProperty.PropertyName)
 				UpdateLineHeight();
 			else if (e.PropertyName == Label.MaxLinesProperty.PropertyName)
 				UpdateMaxLines();
-			else if (e.PropertyName == ImageButton.PaddingProperty.PropertyName)
+			else if (e.PropertyName == Label.PaddingProperty.PropertyName)
 				UpdatePadding();
 		}
 
@@ -242,7 +241,6 @@ namespace Xamarin.Forms.Platform.Android
 			}
 		}
 
-
 		void UpdateLineHeight()
 		{
 			_lastSizeRequest = null;
@@ -274,7 +272,25 @@ namespace Xamarin.Forms.Platform.Android
 					_view.SetTextColor(_labelTextColorDefault);
 					_lastUpdateColor = Color.Default;
 				}
-				_view.Text = Element.Text;
+
+				switch (Element.TextType)
+				{
+
+					case TextType.Html:
+						if (Forms.IsNougatOrNewer)
+							Control.SetText(Html.FromHtml(Element.Text ?? string.Empty, FromHtmlOptions.ModeCompact), TextView.BufferType.Spannable);
+						else
+#pragma warning disable CS0618 // Type or member is obsolete
+							Control.SetText(Html.FromHtml(Element.Text ?? string.Empty), TextView.BufferType.Spannable);
+#pragma warning restore CS0618 // Type or member is obsolete
+						break;
+
+					default:
+						_view.Text = Element.Text;
+
+						break;
+				}
+
 				UpdateColor();
 				UpdateFont();
 
diff --git a/Xamarin.Forms.Platform.UAP/LabelHtmlHelper.cs b/Xamarin.Forms.Platform.UAP/LabelHtmlHelper.cs
new file mode 100644
index 0000000..ba08a30
--- /dev/null
+++ b/Xamarin.Forms.Platform.UAP/LabelHtmlHelper.cs
@@ -0,0 +1,112 @@
+using System.Xml.Linq;
+using Windows.UI.Xaml.Documents;
+
+namespace Xamarin.Forms.Platform.UAP
+{
+	internal static class LabelHtmlHelper
+	{
+		// All the supported HTML tags
+		internal const string ElementB = "B";
+		internal const string ElementBr = "BR";
+		internal const string ElementEm = "EM";
+		internal const string ElementI = "I";
+		internal const string ElementP = "P";
+		internal const string ElementStrong = "STRONG";
+		internal const string ElementU = "U";
+		internal const string ElementUl = "UL";
+		internal const string ElementLi = "LI";
+		internal const string ElementDiv = "DIV";
+
+		public static void ParseText(XElement element, InlineCollection inlines, Label label)
+		{
+			if (element == null)
+				return;
+
+			var currentInlines = inlines;
+			var elementName = element.Name.ToString().ToUpper();
+			switch (elementName)
+			{
+				case ElementB:
+				case ElementStrong:
+					var bold = new Bold();
+					inlines.Add(bold);
+					currentInlines = bold.Inlines;
+					break;
+				case ElementI:
+				case ElementEm:
+					var italic = new Italic();
+					inlines.Add(italic);
+					currentInlines = italic.Inlines;
+					break;
+				case ElementU:
+					var underline = new Underline();
+					inlines.Add(underline);
+					currentInlines = underline.Inlines;
+					break;
+				case ElementBr:
+					inlines.Add(new LineBreak());
+					break;
+				case ElementP:
+					// Add two line breaks, one for the current text and the second for the gap.
+					if (AddLineBreakIfNeeded(inlines))
+					{
+						inlines.Add(new LineBreak());
+					}
+
+					var paragraphSpan = new Windows.UI.Xaml.Documents.Span();
+					inlines.Add(paragraphSpan);
+					currentInlines = paragraphSpan.Inlines;
+					break;
+				case ElementLi:
+					inlines.Add(new LineBreak());
+					inlines.Add(new Run { Text = " • " });
+					break;
+				case ElementUl:
+				case ElementDiv:
+					AddLineBreakIfNeeded(inlines);
+					var divSpan = new Windows.UI.Xaml.Documents.Span();
+					inlines.Add(divSpan);
+					currentInlines = divSpan.Inlines;
+					break;
+			}
+			foreach (var node in element.Nodes())
+			{
+				if (node is XText textElement)
+				{
+					currentInlines.Add(new Run { Text = textElement.Value });
+				}
+				else
+				{
+					ParseText(node as XElement, currentInlines, label);
+				}
+			}
+			// Add newlines for paragraph tags
+			if (elementName == "ElementP")
+			{
+				currentInlines.Add(new LineBreak());
+			}
+		}
+
+		static bool AddLineBreakIfNeeded(InlineCollection inlines)
+		{
+			if (inlines.Count <= 0)
+				return false;
+
+			var lastInline = inlines[inlines.Count - 1];
+			while ((lastInline is Windows.UI.Xaml.Documents.Span))
+			{
+				var span = (Windows.UI.Xaml.Documents.Span)lastInline;
+				if (span.Inlines.Count > 0)
+				{
+					lastInline = span.Inlines[span.Inlines.Count - 1];
+				}
+			}
+
+			if (lastInline is LineBreak)
+				return false;
+
+			inlines.Add(new LineBreak());
+			return true;
+		}
+	}
+}
\ No newline at end of file
diff --git a/Xamarin.Forms.Platform.UAP/LabelRenderer.cs b/Xamarin.Forms.Platform.UAP/LabelRenderer.cs
index 3b9217f..f0c0253 100644
--- a/Xamarin.Forms.Platform.UAP/LabelRenderer.cs
+++ b/Xamarin.Forms.Platform.UAP/LabelRenderer.cs
@@ -1,12 +1,15 @@
 using System;
 using System.Collections.Generic;
 using System.ComponentModel;
+using System.Text.RegularExpressions;
+using System.Xml.Linq;
 using Windows.Foundation;
 using Windows.UI.Text;
 using Windows.UI.Xaml;
 using Windows.UI.Xaml.Automation.Peers;
 using Windows.UI.Xaml.Controls;
 using Windows.UI.Xaml.Documents;
+using Xamarin.Forms.Platform.UAP;
 using Xamarin.Forms.PlatformConfiguration.WindowsSpecific;
 using Specifics = Xamarin.Forms.PlatformConfiguration.WindowsSpecific.Label;
 using WThickness = Windows.UI.Xaml.Thickness;
@@ -155,11 +158,8 @@ namespace Xamarin.Forms.Platform.UWP
 
 		protected override void OnElementPropertyChanged(object sender, PropertyChangedEventArgs e)
 		{
-			if (e.PropertyName == Label.TextProperty.PropertyName ||
-				e.PropertyName == Label.FormattedTextProperty.PropertyName)
-			{
+			if (e.IsOneOf(Label.TextProperty,  Label.FormattedTextProperty, Label.TextTypeProperty))
 				UpdateText(Control);
-			}
 			else if (e.PropertyName == Label.TextColorProperty.PropertyName)
 				UpdateColor(Control);
 			else if (e.PropertyName == Label.HorizontalTextAlignmentProperty.PropertyName || e.PropertyName == Label.VerticalTextAlignmentProperty.PropertyName)
@@ -182,6 +182,7 @@ namespace Xamarin.Forms.Platform.UWP
 				UpdateMaxLines(Control);
 			else if (e.PropertyName == Label.PaddingProperty.PropertyName)
 				UpdatePadding(Control);
+				
 			base.OnElementPropertyChanged(sender, e);
 		}
 
@@ -327,10 +328,22 @@ namespace Xamarin.Forms.Platform.UWP
 			_perfectSizeValid = false;
 
 			if (textBlock == null)
-			{
 				return;
+
+			switch (Element.TextType)
+			{
+				case TextType.Html:
+					UpdateTextHtml(textBlock);
+					break;
+
+				default:
+					UpdateTextPlainText(textBlock);
+					break;
 			}
+		}
 
+		void UpdateTextPlainText(TextBlock textBlock)
+		{
 			Label label = Element;
 			if (label != null)
 			{
@@ -360,6 +373,27 @@ namespace Xamarin.Forms.Platform.UWP
 			}
 		}
 
+		void UpdateTextHtml(TextBlock textBlock)
+		{
+			var text = Element.Text ?? String.Empty;
+
+			// Just in case we are not given text with elements.
+			var modifiedText = string.Format("<div>{0}</div>", text);
+			modifiedText = Regex.Replace(modifiedText, "<br>", "<br></br>", RegexOptions.IgnoreCase);
+			// reset the text because we will add to it.
+			Control.Inlines.Clear();
+			try
+			{
+				var element = XElement.Parse(modifiedText);
+				LabelHtmlHelper.ParseText(element, Control.Inlines, Element);
+			}
+			catch (Exception)
+			{
+				// if anything goes wrong just show the html
+				textBlock.Text = Windows.Data.Html.HtmlUtilities.ConvertToText(Element.Text);
+			}
+		}
+
 		void UpdateDetectReadingOrderFromContent(TextBlock textBlock)
 		{
 			if (Element.IsSet(Specifics.DetectReadingOrderFromContentProperty))
@@ -407,4 +441,4 @@ namespace Xamarin.Forms.Platform.UWP
 					Element.Padding.Bottom);
 		}
 	}
-}
+}
\ No newline at end of file
diff --git a/Xamarin.Forms.Platform.UAP/Xamarin.Forms.Platform.UAP.csproj b/Xamarin.Forms.Platform.UAP/Xamarin.Forms.Platform.UAP.csproj
index 5193420..edea00d 100644
--- a/Xamarin.Forms.Platform.UAP/Xamarin.Forms.Platform.UAP.csproj
+++ b/Xamarin.Forms.Platform.UAP/Xamarin.Forms.Platform.UAP.csproj
@@ -78,6 +78,7 @@
     <Compile Include="ITitleViewRendererController.cs" />
     <Compile Include="IToolbarProvider.cs" />
     <Compile Include="IVisualNativeElementRenderer.cs" />
+    <Compile Include="LabelHtmlHelper.cs" />
     <Compile Include="NativeBindingExtensions.cs" />
     <Compile Include="NativeEventWrapper.cs" />
     <Compile Include="NativePropertyListener.cs" />
diff --git a/Xamarin.Forms.Platform.iOS/Renderers/LabelRenderer.cs b/Xamarin.Forms.Platform.iOS/Renderers/LabelRenderer.cs
index 5e3e5a3..4f3dd23 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/LabelRenderer.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/LabelRenderer.cs
@@ -39,7 +39,8 @@ namespace Xamarin.Forms.Platform.MacOS
 			Label.FormattedTextProperty.PropertyName,
 			Label.LineBreakModeProperty.PropertyName,
 			Label.LineHeightProperty.PropertyName,
-			Label.PaddingProperty.PropertyName
+			Label.PaddingProperty.PropertyName,
+			Label.TextTypeProperty.PropertyName
 		};
 
 		public override SizeRequest GetDesiredSize(double widthConstraint, double heightConstraint)
@@ -216,9 +217,10 @@ namespace Xamarin.Forms.Platform.MacOS
 				UpdateMaxLines();
 			else if (e.PropertyName == Label.PaddingProperty.PropertyName)
 				UpdatePadding();
+			else if (e.PropertyName == Label.TextTypeProperty.PropertyName)
+				UpdateText();
 		}
 
-
 		protected override NativeLabel CreateNativeControl()
 		{
 #if __MOBILE__
@@ -236,6 +238,9 @@ namespace Xamarin.Forms.Platform.MacOS
 
 		void UpdateTextDecorations()
 		{
+			if (Element?.TextType != TextType.Text)
+				return;
+
 			if (!Element.IsSet(Label.TextDecorationsProperty))
 				return;
 
@@ -275,6 +280,7 @@ namespace Xamarin.Forms.Platform.MacOS
 #else
 			Control.AttributedStringValue = newAttributedText;
 #endif
+			_perfectSizeValid = false;
 		}
 
 #if __MOBILE__
@@ -372,15 +378,34 @@ namespace Xamarin.Forms.Platform.MacOS
 		{
 #if __MOBILE__
 
+			if (Element?.TextType != TextType.Text)
+				return;
+
 			var textAttr = Control.AttributedText.AddCharacterSpacing(Element.Text, Element.CharacterSpacing);
 
 			if (textAttr != null)
 				Control.AttributedText = textAttr;
+				
+			_perfectSizeValid = false;
 #endif
 		}
 
 		void UpdateText()
 		{
+			switch (Element.TextType)
+			{
+				case TextType.Html:
+					UpdateTextHtml();
+					break;
+
+				default:
+					UpdateTextPlainText();
+					break;
+			}
+		}
+
+		void UpdateTextPlainText()
+		{
 			_formatted = Element.FormattedText;
 			if (_formatted == null && Element.LineHeight >= 0)
 				_formatted = Element.Text;
@@ -407,10 +432,42 @@ namespace Xamarin.Forms.Platform.MacOS
 #else
 			Control.AttributedStringValue = _formatted.ToAttributed(Element, Element.TextColor, Element.HorizontalTextAlignment, Element.LineHeight);
 #endif
+			_perfectSizeValid = false;
+		}
+
+		void UpdateTextHtml()
+		{
+			string text = Element.Text ?? string.Empty;
+
+#if __MOBILE__
+			var attr = new NSAttributedStringDocumentAttributes
+			{
+				DocumentType = NSDocumentType.HTML
+			};
+
+			NSError nsError = null;
+
+			Control.AttributedText = new NSAttributedString(text, attr, ref nsError);
+
+#else
+			var attr = new NSAttributedStringDocumentAttributes
+			{
+				DocumentType = NSDocumentType.HTML
+			};
+
+			var htmlData = new NSMutableData();
+			htmlData.SetData(text);
+
+			Control.AttributedStringValue = new NSAttributedString(htmlData, attr, out _);
+#endif
+			_perfectSizeValid = false;
 		}
 
 		void UpdateFont()
 		{
+			if (Element?.TextType != TextType.Text)
+				return;
+
 			if (IsTextFormatted)
 			{
 				UpdateFormattedText();
@@ -427,6 +484,9 @@ namespace Xamarin.Forms.Platform.MacOS
 
 		void UpdateTextColor()
 		{
+			if (Element?.TextType != TextType.Text)
+				return;
+
 			if (IsTextFormatted)
 			{
 				UpdateFormattedText();
@@ -545,4 +605,4 @@ namespace Xamarin.Forms.Platform.MacOS
 		}
 #endif
 	}
-}
\ No newline at end of file
+}
-- 
2.7.4