[Core] Added TextTransform property

Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Issue3667.cs

@@ -0,0 +1,95 @@
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+
+#if UITEST
+using NUnit.Framework;
+using Xamarin.UITest;
+#endif
+
+namespace Xamarin.Forms.Controls.Issues
+{
+	[Preserve(AllMembers = true)]
+	[Issue(IssueTracker.Github, 3667, "[Enhancement] Add text-transforms to Label", PlatformAffected.All)]
+	public class Issue3667 : TestContentPage
+	{
+		string text = "Lorem ipsum dolor sit amet, consectetur adipiscing elit, sed do eiusmod tempor incididunt ut labore et dolore magna aliqua.";
+
+		protected override void Init()
+		{
+			var text2 = "Malesuada fames ac turpis egestas maecenas pharetra convallis. Dictum varius duis at consectetur lorem donec massa. Augue interdum velit euismod in pellentesque.";
+			var transform = TextTransform.None;
+
+			var list = new ITextElement[] {
+				new Label { Text = text },
+				new Entry { Text = "Entry text" },
+				new Editor { Text = "Editor text" },
+				new SearchBar { Text = "SearchBar text" },
+				new Button { Text = "Button text" },
+			};
+
+			var statusLabel = new Label
+			{
+				Text = "Current TextTransform is None",
+				BackgroundColor = Color.Aqua,
+				TextTransform = transform
+			};
+			var but = new Button
+			{
+				Text = "Change TextTransform",
+				Command = new Command(() =>
+				{
+					if (++transform > TextTransform.Uppercase)
+						transform = TextTransform.None;
+					foreach (var item in list)
+						item.TextTransform = transform;
+					statusLabel.Text = $"Current TextTransform is {transform}";
+				})
+			};
+
+			var layout = new StackLayout
+			{
+				Children = {
+					statusLabel,
+					but
+				}
+			};
+
+			foreach (var item in list)
+			{
+				item.TextTransform = transform;
+				layout.Children.Add(item as View);
+			}
+
+			layout.Children.Add(new Label
+			{
+				Text = "[Lowercase] " + text2,
+				TextTransform = TextTransform.Lowercase
+			});
+			layout.Children.Add(new Label
+			{
+				Text = "[Uppercase] " + text2,
+				TextTransform = TextTransform.Uppercase
+			});
+
+			Content = layout;
+		}
+
+#if UITEST
+		[Test]
+		public void Issue3667Tests ()
+		{
+			RunningApp.WaitForElement(query => query.Text(text));
+			RunningApp.Tap("Change TextTransform");
+			RunningApp.WaitForElement(query => query.Text(text));
+			RunningApp.Tap("Change TextTransform");
+			RunningApp.WaitForElement(query => query.Text(text.ToLowerInvariant()));
+			RunningApp.Tap("Change TextTransform");
+			RunningApp.WaitForElement(query => query.Text(text.ToUpperInvariant()));
+			RunningApp.Tap("Change TextTransform");
+			RunningApp.WaitForElement(query => query.Text(text));
+		}
+#endif
+	}
+}
+
+

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

@@ -1201,6 +1201,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)GitHub1776.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue3408.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue3413.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Issue3667.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue3525.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue3275.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Issue3884.cs" />

Xamarin.Forms.Core.UnitTests/LabelTests.cs

@@ -60,6 +60,18 @@ public void InvalidateMeasureWhenTextChanges ()
 			label.Text = "Foo";
 			Assert.IsTrue (fired);
 
+			fired = false;
+			label.TextTransform = TextTransform.Lowercase;
+			Assert.IsTrue(fired);
+
+			fired = false;
+			label.TextTransform = TextTransform.Uppercase;
+			Assert.IsTrue(fired);
+
+			fired = false;
+			label.TextTransform = TextTransform.None;
+			Assert.IsTrue(fired);
+
 			var fs = new FormattedString ();
 
 			fired = false;

Xamarin.Forms.Core/Button.cs

@@ -35,6 +35,8 @@ public class Button : View, IFontElement, ITextElement, IBorderElement, IButtonC
 
 		public static readonly BindableProperty FontSizeProperty = FontElement.FontSizeProperty;
 
+		public static readonly BindableProperty TextTransformProperty = TextElement.TextTransformProperty;
+
 		public static readonly BindableProperty FontAttributesProperty = FontElement.FontAttributesProperty;
 
 		public static readonly BindableProperty BorderWidthProperty = BindableProperty.Create("BorderWidth", typeof(double), typeof(Button), -1d);
@@ -209,6 +211,12 @@ public double FontSize
 			set { SetValue(FontSizeProperty, value); }
 		}
 
+		public TextTransform TextTransform
+		{
+			get => (TextTransform)GetValue(TextTransformProperty);
+			set => SetValue(TextTransformProperty, value);
+		}
+
 		public event EventHandler Clicked;
 		public event EventHandler Pressed;
 
@@ -361,6 +369,11 @@ void IImageController.SetIsLoading(bool isLoading)
 		bool IBorderElement.IsBorderColorSet() => IsSet(BorderColorProperty);
 		bool IBorderElement.IsBorderWidthSet() => IsSet(BorderWidthProperty);
 
+		void ITextElement.OnTextTransformChanged(TextTransform oldValue, TextTransform newValue)
+			=> InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
+
+		public virtual string UpdateFormsText(string source, TextTransform textTransform)
+			=> TextTransformUtilites.GetTransformedText(source, textTransform);
 
 		[DebuggerDisplay("Image Position = {Position}, Spacing = {Spacing}")]
 		[TypeConverter(typeof(ButtonContentTypeConverter))]

Xamarin.Forms.Core/DatePicker.cs

@@ -30,6 +30,8 @@ public class DatePicker : View, IFontElement, ITextElement, IElementConfiguratio
 
 		public static readonly BindableProperty FontAttributesProperty = FontElement.FontAttributesProperty;
 
+		public static readonly BindableProperty TextTransformProperty = TextElement.TextTransformProperty;
+
 		readonly Lazy<PlatformConfigurationRegistry<DatePicker>> _platformConfigurationRegistry;
 
 		public DatePicker()
@@ -49,6 +51,12 @@ public string Format
 			set { SetValue(FormatProperty, value); }
 		}
 
+		public TextTransform TextTransform
+		{
+			get { return (TextTransform)GetValue(TextTransformProperty); }
+			set { SetValue(TextTransformProperty, value); }
+		}
+
 		public DateTime MaximumDate
 		{
 			get { return (DateTime)GetValue(MaximumDateProperty); }
@@ -107,6 +115,13 @@ double IFontElement.FontSizeDefaultValueCreator() =>
 		void IFontElement.OnFontAttributesChanged(FontAttributes oldValue, FontAttributes newValue) =>
 			InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
 
+		void ITextElement.OnTextTransformChanged(TextTransform oldValue, TextTransform newValue)
+		{
+		}
+
+		public virtual string UpdateFormsText(string source, TextTransform textTransform)
+			=> TextTransformUtilites.GetTransformedText(source, textTransform);
+
 		public event EventHandler<DateChangedEventArgs> DateSelected;
 
 		static object CoerceDate(BindableObject bindable, object value)

Xamarin.Forms.Core/ITextElement.cs

@@ -1,4 +1,5 @@
 using System;
+using Xamarin.Forms.Internals;
 
 namespace Xamarin.Forms
 {
@@ -14,5 +15,11 @@ interface ITextElement
 
 		//note to implementor: but implement these methods explicitly
 		void OnCharacterSpacingPropertyChanged(double oldValue, double newValue);
+
+		TextTransform TextTransform { get; set; }
+
+		void OnTextTransformChanged(TextTransform oldValue, TextTransform newValue);
+
+		string UpdateFormsText(string original, TextTransform transform);
 	}
-}
+}

Xamarin.Forms.Core/InputView.cs

@@ -1,4 +1,5 @@
 using System;
+using Xamarin.Forms.Internals;
 
 namespace Xamarin.Forms
 {
@@ -24,6 +25,8 @@ public class InputView : View, IPlaceholderElement, ITextElement
 
 		public static readonly BindableProperty CharacterSpacingProperty = TextElement.CharacterSpacingProperty;
 
+		public static readonly BindableProperty TextTransformProperty = TextElement.TextTransformProperty;
+
 		public int MaxLength
 		{
 			get => (int)GetValue(MaxLengthProperty);
@@ -82,6 +85,12 @@ public double CharacterSpacing
 			set => SetValue(CharacterSpacingProperty, value);
 		}
 
+		public TextTransform TextTransform
+		{
+			get => (TextTransform)GetValue(TextTransformProperty);
+			set => SetValue(TextTransformProperty, value);
+		}
+
 		public event EventHandler<TextChangedEventArgs> TextChanged;
 
 		protected virtual void OnTextChanged(string oldValue, string newValue)
@@ -97,6 +106,16 @@ void ITextElement.OnCharacterSpacingPropertyChanged(double oldValue, double newV
 		{
 			InvalidateMeasure();
 		}
+
+		public void OnTextTransformChanged(TextTransform oldValue, TextTransform newValue)
+		{
+			InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
+		}
+
+		public string UpdateFormsText(string original, TextTransform transform)
+		{
+			return TextTransformUtilites.GetTransformedText(original, transform);
+		}
 	}
 
 	public enum ClearButtonVisibility

Xamarin.Forms.Core/Internals/TextTransformUtilites.cs

@@ -0,0 +1,46 @@
+using System.ComponentModel;
+
+namespace Xamarin.Forms.Internals
+{
+	[EditorBrowsable(EditorBrowsableState.Never)]
+	public static class TextTransformUtilites
+	{
+		[EditorBrowsable(EditorBrowsableState.Never)]
+		public static string GetTransformedText(string source, TextTransform textTransform)
+		{
+			if (string.IsNullOrEmpty(source))
+				return string.Empty;
+
+			switch (textTransform)
+			{
+				case TextTransform.None:
+				default:
+					return source;
+				case TextTransform.Lowercase:
+					return source.ToLowerInvariant();
+				case TextTransform.Uppercase:
+					return source.ToUpperInvariant();
+			}
+		}
+
+
+		[EditorBrowsable(EditorBrowsableState.Never)]
+		public static void SetPlainText(InputView inputView, string nativeText)
+		{
+			if (inputView == null)
+				return;
+
+			var textTransform = inputView.TextTransform;
+			var nativeTextWithTransform = inputView.UpdateFormsText(nativeText, textTransform);
+			var formsText = inputView.UpdateFormsText(inputView.Text, textTransform);
+
+			if ((string.IsNullOrEmpty(formsText) && nativeText.Length == 0))
+				return;
+
+			if (formsText == nativeTextWithTransform)
+				return;
+
+			inputView.SetValueFromRenderer(InputView.TextProperty, nativeText);
+		}
+	}
+}

Xamarin.Forms.Core/Label.cs

@@ -4,6 +4,7 @@
 using System.Collections.Specialized;
 using System.ComponentModel;
 using System.Linq;
+using System.Text;
 using Xamarin.Forms.Internals;
 using Xamarin.Forms.Platform;
 
@@ -40,6 +41,8 @@ public class Label : View, IFontElement, ITextElement, ITextAlignmentElement, IL
 
 		public static readonly BindableProperty FontAttributesProperty = FontElement.FontAttributesProperty;
 
+		public static readonly BindableProperty TextTransformProperty = TextElement.TextTransformProperty;
+
 		public static readonly BindableProperty TextDecorationsProperty = DecorableTextElement.TextDecorationsProperty;
 
 		public static readonly BindableProperty FormattedTextProperty = BindableProperty.Create(nameof(FormattedText), typeof(FormattedString), typeof(Label), default(FormattedString),
@@ -75,6 +78,15 @@ public class Label : View, IFontElement, ITextElement, ITextAlignmentElement, IL
 					label.Text = null;
 			});
 
+		public TextTransform TextTransform
+		{
+			get { return (TextTransform)GetValue(TextTransformProperty); }
+			set { SetValue(TextTransformProperty, value); }
+		}
+
+		public virtual string UpdateFormsText(string source, TextTransform textTransform)
+			=> TextTransformUtilites.GetTransformedText(source, textTransform);
+
 		public static readonly BindableProperty LineBreakModeProperty = BindableProperty.Create(nameof(LineBreakMode), typeof(LineBreakMode), typeof(Label), LineBreakMode.WordWrap,
 			propertyChanged: (bindable, oldvalue, newvalue) => ((Label)bindable).InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged));
 
@@ -244,6 +256,10 @@ void OnFormattedTextChanging(object sender, PropertyChangingEventArgs e)
 		{
 			OnPropertyChanging("FormattedText");
 		}
+
+		void ITextElement.OnTextTransformChanged(TextTransform oldValue, TextTransform newValue) =>
+			InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
+
 		void OnFormattedTextChanged(object sender, PropertyChangedEventArgs e)
 		{
 			OnPropertyChanged("FormattedText");

Xamarin.Forms.Core/Picker.cs

@@ -40,7 +40,9 @@ public class Picker : View, IFontElement, ITextElement, IElementConfiguration<Pi
 		public static readonly BindableProperty FontSizeProperty = FontElement.FontSizeProperty;
 
 		public static readonly BindableProperty FontAttributesProperty = FontElement.FontAttributesProperty;
-
+
+		public static readonly BindableProperty TextTransformProperty = TextElement.TextTransformProperty;
+
 		readonly Lazy<PlatformConfigurationRegistry<Picker>> _platformConfigurationRegistry;
 
 		public Picker()
@@ -67,6 +69,15 @@ public double FontSize
 			set { SetValue(FontSizeProperty, value); }
 		}
 
+		public TextTransform TextTransform
+		{
+			get => (TextTransform)GetValue(TextTransformProperty);
+			set => SetValue(TextTransformProperty, value);
+		}
+
+		public virtual string UpdateFormsText(string source, TextTransform textTransform)
+			=> TextTransformUtilites.GetTransformedText(source, textTransform);
+
 		void IFontElement.OnFontFamilyChanged(string oldValue, string newValue) =>
 			InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
 
@@ -82,6 +93,9 @@ double IFontElement.FontSizeDefaultValueCreator() =>
 		void IFontElement.OnFontAttributesChanged(FontAttributes oldValue, FontAttributes newValue) =>
 			InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
 
+		void ITextElement.OnTextTransformChanged(TextTransform oldValue, TextTransform newValue) =>
+			InvalidateMeasureInternal(InvalidationTrigger.MeasureChanged);
+
 		public IList<string> Items { get; } = new LockableObservableListWrapper();
 
 		public IList ItemsSource

Xamarin.Forms.Core/Properties/AssemblyInfo.cs

@@ -51,6 +51,7 @@
 [assembly: StyleProperty("border-width", typeof(IBorderElement), nameof(BorderElement.BorderWidthProperty))]
 [assembly: StyleProperty("color", typeof(IColorElement), nameof(ColorElement.ColorProperty), Inherited = true)]
 [assembly: StyleProperty("color", typeof(ITextElement), nameof(TextElement.TextColorProperty), Inherited = true)]
+[assembly: StyleProperty("text-transform", typeof(ITextElement), nameof(TextElement.TextTransformProperty), Inherited = true)]
 [assembly: StyleProperty("color", typeof(ProgressBar), nameof(ProgressBar.ProgressColorProperty))]
 [assembly: StyleProperty("color", typeof(Switch), nameof(Switch.OnColorProperty))]
 [assembly: StyleProperty("column-gap", typeof(Grid), nameof(Grid.ColumnSpacingProperty))]