Add tests for default colors

src/Core/src/Platform/Android/EditTextExtensions.cs

@@ -36,7 +36,8 @@ public static void UpdateTextColor(this AppCompatEditText editText, ITextStyle e
 
 			if (textColor == null)
 			{
-				editText.SetTextColor(defaultColor);
+				if (defaultColor != null)
+					editText.SetTextColor(defaultColor);
 			}
 			else
 			{

src/Core/src/Platform/Android/TextViewExtensions.cs

@@ -22,7 +22,10 @@ public static void UpdateText(this TextView textView, string newText)
 
 		public static void UpdateTextColor(this TextView textView, ITextStyle textStyle, Graphics.Color defaultColor)
 		{
-			textView.SetTextColor(textStyle.TextColor?.ToNative() ?? defaultColor.ToNative());
+			var textColor = textStyle.TextColor?.ToNative() ?? defaultColor?.ToNative();
+
+			if (textColor != null)
+				textView.SetTextColor(textColor.Value);
 		}
 
 		public static void UpdateTextColor(this TextView textView, ITextStyle textStyle) =>

src/Core/tests/DeviceTests/Handlers/Button/ButtonHandlerTests.cs

@@ -33,6 +33,18 @@ public async Task TextColorInitializesCorrectly()
 			await ValidatePropertyInitValue(button, () => button.TextColor, GetNativeTextColor, button.TextColor);
 		}
 
+		[Fact(DisplayName = "Null Text Color Doesn't Crash")]
+		public async Task NullTextColorDoesntCrash()
+		{
+			var button = new ButtonStub()
+			{
+				Text = "Test",
+				TextColor = null
+			};
+
+			await CreateHandlerAsync(button);
+		}
+
 		[Fact(DisplayName = "Click event fires Correctly")]
 		public async Task ClickEventFires()
 		{

src/Core/tests/DeviceTests/Handlers/DatePicker/DatePickerHandlerTests.cs

@@ -32,6 +32,18 @@ public async Task TextColorInitializesCorrectly()
 			await ValidatePropertyInitValue(datePicker, () => datePicker.TextColor, GetNativeTextColor, datePicker.TextColor);
 		}
 
+		[Fact(DisplayName = "Null Text Color Doesn't Crash")]
+		public async Task NullTextColorDoesntCrash()
+		{
+			var datePicker = new DatePickerStub()
+			{
+				Date = DateTime.Today,
+				TextColor = null
+			};
+
+			await CreateHandlerAsync(datePicker);
+		}
+
 		[Theory(DisplayName = "Font Size Initializes Correctly")]
 		[InlineData(1)]
 		[InlineData(10)]

src/Core/tests/DeviceTests/Handlers/Editor/EditorHandlerTests.cs

@@ -55,6 +55,18 @@ public async Task TextColorInitializesCorrectly()
 			await ValidatePropertyInitValue(editor, () => editor.TextColor, GetNativeTextColor, editor.TextColor);
 		}
 
+		[Fact(DisplayName = "Null Text Color Doesn't Crash")]
+		public async Task NullTextColorDoesntCrash()
+		{
+			var editor = new EditorStub()
+			{
+				Text = "Test",
+				TextColor = null
+			};
+
+			await CreateHandlerAsync(editor);
+		}
+
 		[Fact(DisplayName = "PlaceholderColor Initializes Correctly")]
 		public async Task PlaceholderColorInitializesCorrectly()
 		{
@@ -67,6 +79,18 @@ public async Task PlaceholderColorInitializesCorrectly()
 			await ValidatePropertyInitValue(editor, () => editor.PlaceholderColor, GetNativePlaceholderColor, editor.PlaceholderColor);
 		}
 
+		[Fact(DisplayName = "Null Placeholder Color Doesn't Crash")]
+		public async Task NullPlaceholderColorDoesntCrash()
+		{
+			var editor = new EditorStub()
+			{
+				Placeholder = "Test",
+				PlaceholderColor = null
+			};
+
+			await CreateHandlerAsync(editor);
+		}
+
 		[Theory(DisplayName = "PlaceholderColor Updates Correctly")]
 		[InlineData(0xFF0000, 0x0000FF)]
 		[InlineData(0x0000FF, 0xFF0000)]

src/Core/tests/DeviceTests/Handlers/Entry/EntryHandlerTests.cs

@@ -33,6 +33,18 @@ public async Task TextColorInitializesCorrectly()
 			await ValidatePropertyInitValue(entry, () => entry.TextColor, GetNativeTextColor, entry.TextColor);
 		}
 
+		[Fact(DisplayName = "Null Text Color Doesn't Crash")]
+		public async Task NullTextColorDoesntCrash()
+		{
+			var entry = new EntryStub()
+			{
+				Text = "Test",
+				TextColor = null
+			};
+
+			await CreateHandlerAsync(entry);
+		}
+
 		[Theory(DisplayName = "IsPassword Initializes Correctly")]
 		[InlineData(true)]
 		[InlineData(false)]
@@ -51,10 +63,10 @@ public async Task PlaceholderInitializesCorrectly()
 		{
 			var entry = new EntryStub()
 			{
-				Text = "Placeholder"
+				Placeholder = "Placeholder"
 			};
 
-			await ValidatePropertyInitValue(entry, () => entry.Placeholder, GetNativePlaceholder, entry.Placeholder);
+			await ValidatePropertyInitValue(entry, () => entry.Placeholder, GetNativePlaceholder, "Placeholder");
 		}
 
 		[Theory(DisplayName = "Is Text Prediction Enabled")]

src/Core/tests/DeviceTests/Handlers/Label/LabelHandlerTests.cs

@@ -46,6 +46,18 @@ public async Task TextColorInitializesCorrectly()
 			await ValidatePropertyInitValue(label, () => label.TextColor, GetNativeTextColor, label.TextColor);
 		}
 
+		[Fact(DisplayName = "Null Text Color Doesn't Crash")]
+		public async Task NullTextColorDoesntCrash()
+		{
+			var label = new LabelStub()
+			{
+				Text = "Test",
+				TextColor = null
+			};
+
+			await CreateHandlerAsync(label);
+		}
+
 		[Theory(DisplayName = "Font Size Initializes Correctly")]
 		[InlineData(1)]
 		[InlineData(10)]

src/Core/tests/DeviceTests/Handlers/ProgressBar/ProgressBarTests.cs

@@ -18,12 +18,23 @@ public async Task ProgressInitializesCorrectly(double progress)
 		{
 			var progressBar = new ProgressBarStub()
 			{
-				Progress = progress
+				Progress = progress,
 			};
 
 			var expected = progressBar.Progress;
 
 			await ValidatePropertyInitValue(progressBar, () => progressBar.Progress, GetNativeProgress, progressBar.Progress);
 		}
+
+		[Fact(DisplayName = "Null Progress Color Doesn't Crash")]
+		public async Task NullProgressColorDoesntCrash()
+		{
+			var progressBar = new ProgressBarStub()
+			{
+				ProgressColor = null
+			};
+
+			await CreateHandlerAsync(progressBar);
+		}
 	}
 }

src/Core/tests/DeviceTests/Handlers/SearchBar/SearchBarHandlerTests.cs

@@ -52,7 +52,19 @@ public async Task TextColorInitializesCorrectly()
 				TextColor = Colors.Red
 			};
 
-			await ValidatePropertyInitValue(searchBar, () => searchBar.TextColor, GetNativeTextColor, searchBar.TextColor);
+			await ValidatePropertyInitValue(searchBar, () => searchBar.TextColor, GetNativeTextColor, Colors.Red);
+		}
+
+		[Fact(DisplayName = "Null Text Color Doesn't Crash")]
+		public async Task NullTextColorDoesntCrash()
+		{
+			var searchBar = new SearchBarStub
+			{
+				Text = "TextColor",
+				TextColor = null,
+			};
+
+			await CreateHandlerAsync(searchBar);
 		}
 
 		[Fact(DisplayName = "Placeholder Initializes Correctly")]
@@ -130,5 +142,16 @@ public async Task CancelButtonColorInitializeCorrectly()
 
 			await ValidateHasColor(searchBar, Colors.MediumPurple, () => searchBar.CancelButtonColor = Colors.MediumPurple);
 		}
+
+		[Fact(DisplayName = "Null Cancel Button Color Doesn't Crash")]
+		public async Task NullCancelButtonColorDoesntCrash()
+		{
+			var searchBar = new SearchBarStub
+			{
+				CancelButtonColor = null,
+			};
+
+			await CreateHandlerAsync(searchBar);
+		}
 	}
 }

src/Core/tests/DeviceTests/Handlers/Slider/SliderHandlerTests.cs

@@ -64,6 +64,17 @@ public async Task ThumbColorInitializesCorrectly()
 			await ValidateNativeThumbColor(slider, Colors.Purple);
 		}
 
+		[Fact(DisplayName = "Null Thumb Color Doesn't Crash")]
+		public async Task NullThumbColorDoesntCrash()
+		{
+			var slider = new SliderStub()
+			{
+				ThumbColor = null,
+			};
+
+			await CreateHandlerAsync(slider);
+		}
+
 #if !__ANDROID__ // Android native control behavior works differently; see SliderHandlerTests.Android.cs
 		[Fact(DisplayName = "Value Initializes Correctly")]
 		public async Task ValueInitializesCorrectly()

src/Core/tests/DeviceTests/Handlers/Switch/SwitchHandlerTests.cs

@@ -58,6 +58,19 @@ public async Task ThumbColorInitializesCorrectly()
 			await ValidateThumbColor(switchStub, Colors.Blue);
 		}
 
+
+		[Fact(DisplayName = "Null Thumb Color Doesn't Crash")]
+		public async Task NullThumbColorDoesntCrash()
+		{
+			var switchStub = new SwitchStub()
+			{
+				IsOn = true,
+				ThumbColor = null,
+			};
+
+			await CreateHandlerAsync(switchStub);
+		}
+
 		[Fact(DisplayName = "Track Color Updates Correctly")]
 		public async Task ThumbColorUpdatesCorrectly()
 		{

src/Core/tests/DeviceTests/Handlers/TimePicker/TimePickerHandlerTests.Android.cs

@@ -2,8 +2,10 @@
 using System.Threading.Tasks;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Maui.DeviceTests.Stubs;
+using Microsoft.Maui.Graphics;
 using Microsoft.Maui.Handlers;
 using Xunit;
+using AColor = Android.Graphics.Color;
 
 namespace Microsoft.Maui.DeviceTests
 {
@@ -91,6 +93,13 @@ double GetNativeCharacterSpacing(TimePickerHandler timePickerHandler)
 			return -1;
 		}
 
+		Color GetNativeTextColor(TimePickerHandler timePickerHandler)
+		{
+			int currentTextColorInt = GetNativeTimePicker(timePickerHandler).CurrentTextColor;
+			AColor currentTextColor = new AColor(currentTextColorInt);
+			return currentTextColor.ToColor();
+		}
+
 		double GetNativeUnscaledFontSize(TimePickerHandler timePickerHandler)
 		{
 			var mauiTimePicker = GetNativeTimePicker(timePickerHandler);

src/Core/tests/DeviceTests/Handlers/TimePicker/TimePickerHandlerTests.cs

@@ -1,6 +1,7 @@
 using System;
 using System.Threading.Tasks;
 using Microsoft.Maui.DeviceTests.Stubs;
+using Microsoft.Maui.Graphics;
 using Microsoft.Maui.Handlers;
 using Xunit;
 
@@ -54,5 +55,17 @@ public async Task FontAttributesInitializeCorrectly(FontWeight weight, bool isBo
 			await ValidatePropertyInitValue(timePicker, () => timePicker.Font.Weight == FontWeight.Bold, GetNativeIsBold, isBold);
 			await ValidatePropertyInitValue(timePicker, () => timePicker.Font.FontSlant == FontSlant.Italic, GetNativeIsItalic, isItalic);
 		}
+
+		[Fact(DisplayName = "Null Text Color Doesn't Crash")]
+		public async Task NullTextColorDoesntCrash()
+		{
+			var timePicker = new TimePickerStub()
+			{
+				Time = DateTime.Now.TimeOfDay,
+				TextColor = null
+			};
+
+			await CreateHandlerAsync(timePicker);
+		}
 	}
 }

src/Core/tests/DeviceTests/Handlers/TimePicker/TimePickerHandlerTests.iOS.cs

@@ -2,6 +2,7 @@
 using System.Threading.Tasks;
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Maui.DeviceTests.Stubs;
+using Microsoft.Maui.Graphics;
 using Microsoft.Maui.Handlers;
 using UIKit;
 using Xunit;
@@ -62,6 +63,9 @@ public async Task FontFamilyInitializesCorrectly(string family)
 		MauiTimePicker GetNativeTimePicker(TimePickerHandler timePickerHandler) =>
 			(MauiTimePicker)timePickerHandler.NativeView;
 
+		Color GetNativeTextColor(TimePickerHandler timePickerHandler) =>
+			GetNativeTimePicker(timePickerHandler).TextColor.ToColor();
+
 		async Task ValidateTime(ITimePicker timePickerStub, Action action = null)
 		{
 			var actual = await GetValueAsync(timePickerStub, handler =>