Add TextColor Property to Picker, TimePicker, DatePicker (#84)

* Add TextColor property to TimePicker
Add TextColor page to TimePicker gallery
Add TimePicker color toggling to color toggle test page
Split color toggle tests up among tabs

* Implement TimePicker.TextColor in iOS

* Implement TimePicker.TextColor for WinRT tablet

* Add IsEnabled=false tests to DefaultColorToggleTest Button and TimePicker
Consolidate ColorStates array
Fix IsEnabled changing color bug on iOS

* Implement TimePicker.TextColor for WP8

* Add TextColor property to DatePicker
Add DatePicker section to DefaultColorToggleTest
Impement DatePicker.TextColor for WP8

* Implement DatePicker.TextColor for WinRT/UWP/Windows Phone 8.1

* Implement DatePicker.TextColor for iOS

* Add TextColor to DatePicker Gallery Page

* Implement DatePicker.TextColor for Android

* Add Picker Gallery page for TextColor
Implement Picker.TextColor on Android
Consolidate TextColor management for Button, Picker, DatePicker, TimePicker
Implement

* Add untracked TextColorSwitcher
Implement Picker.TextColor in iOS

* Implement Picker.TextColor in WinRT/UWP/Windows Phone 8.1
Remove Pioker Loaded handlers in Dispose

* Implement Picker.TextColor in WP8

* Removed unused field
Update ignored warnings

* Update docs

* Use nameof() for BindableProperties

* Cleanup

* Fix custom renderer crashes for classes using TextColorSwitcher

* Correct property name references

* Fix typo and 'if' formatting

* Add missing else

3 files changed, 49 insertions, 0 deletions

diff --git a/Xamarin.Forms.Platform.iOS/Renderers/DatePickerRenderer.cs b/Xamarin.Forms.Platform.iOS/Renderers/DatePickerRenderer.cs
index fd2b1549..6d70d7c5 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/DatePickerRenderer.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/DatePickerRenderer.cs
@@ -36,6 +36,7 @@ namespace Xamarin.Forms.Platform.iOS
 	public class DatePickerRenderer : ViewRenderer<DatePicker, UITextField>
 	{
 		UIDatePicker _picker;
+		UIColor _defaultTextColor;
 
 		protected override void OnElementChanged(ElementChangedEventArgs<DatePicker> e)
 		{
@@ -62,6 +63,8 @@ namespace Xamarin.Forms.Platform.iOS
 				entry.InputView = _picker;
 				entry.InputAccessoryView = toolbar;
 
+				_defaultTextColor = entry.TextColor;
+
 				SetNativeControl(entry);
 			}
 
@@ -70,6 +73,7 @@ namespace Xamarin.Forms.Platform.iOS
 				UpdateDateFromModel(false);
 				UpdateMaximumDate();
 				UpdateMinimumDate();
+				UpdateTextColor();
 			}
 		}
 
@@ -83,6 +87,8 @@ namespace Xamarin.Forms.Platform.iOS
 				UpdateMinimumDate();
 			else if (e.PropertyName == DatePicker.MaximumDateProperty.PropertyName)
 				UpdateMaximumDate();
+			else if (e.PropertyName == DatePicker.TextColorProperty.PropertyName || e.PropertyName == VisualElement.IsEnabledProperty.PropertyName)
+				UpdateTextColor();
 		}
 
 		void HandleValueChanged(object sender, EventArgs e)
@@ -118,5 +124,15 @@ namespace Xamarin.Forms.Platform.iOS
 		{
 			_picker.MinimumDate = Element.MinimumDate.ToNSDate();
 		}
+
+		void UpdateTextColor()
+		{
+			var textColor = Element.TextColor;
+
+			if (textColor.IsDefault || !Element.IsEnabled)
+				Control.TextColor = _defaultTextColor;
+			else
+				Control.TextColor = textColor.ToUIColor();
+		}
 	}
 }
\ No newline at end of file
diff --git a/Xamarin.Forms.Platform.iOS/Renderers/PickerRenderer.cs b/Xamarin.Forms.Platform.iOS/Renderers/PickerRenderer.cs
index e47d2fa4..7b5461e2 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/PickerRenderer.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/PickerRenderer.cs
@@ -22,6 +22,7 @@ namespace Xamarin.Forms.Platform.iOS
 	public class PickerRenderer : ViewRenderer<Picker, UITextField>
 	{
 		UIPickerView _picker;
+		UIColor _defaultTextColor;
 
 		protected override void OnElementChanged(ElementChangedEventArgs<Picker> e)
 		{
@@ -56,12 +57,15 @@ namespace Xamarin.Forms.Platform.iOS
 					entry.InputView = _picker;
 					entry.InputAccessoryView = toolbar;
 
+					_defaultTextColor = entry.TextColor;
+
 					SetNativeControl(entry);
 				}
 
 				_picker.Model = new PickerSource(this);
 
 				UpdatePicker();
+				UpdateTextColor();
 
 				((ObservableList<string>)e.NewElement.Items).CollectionChanged += RowsCollectionChanged;
 			}
@@ -76,6 +80,8 @@ namespace Xamarin.Forms.Platform.iOS
 				UpdatePicker();
 			if (e.PropertyName == Picker.SelectedIndexProperty.PropertyName)
 				UpdatePicker();
+			if (e.PropertyName == Picker.TextColorProperty.PropertyName || e.PropertyName == VisualElement.IsEnabledProperty.PropertyName)
+				UpdateTextColor();
 		}
 
 		void OnEnded(object sender, EventArgs eventArgs)
@@ -133,6 +139,16 @@ namespace Xamarin.Forms.Platform.iOS
 			_picker.Select(Math.Max(formsIndex, 0), 0, true);
 		}
 
+		void UpdateTextColor()
+		{
+			var textColor = Element.TextColor;
+
+			if (textColor.IsDefault || !Element.IsEnabled)
+				Control.TextColor = _defaultTextColor;
+			else
+				Control.TextColor = textColor.ToUIColor();
+		}
+
 		class PickerSource : UIPickerViewModel
 		{
 			readonly PickerRenderer _renderer;
diff --git a/Xamarin.Forms.Platform.iOS/Renderers/TimePickerRenderer.cs b/Xamarin.Forms.Platform.iOS/Renderers/TimePickerRenderer.cs
index 85d3ad35..55dbf1c8 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/TimePickerRenderer.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/TimePickerRenderer.cs
@@ -24,6 +24,7 @@ namespace Xamarin.Forms.Platform.iOS
 	public class TimePickerRenderer : ViewRenderer<TimePicker, UITextField>
 	{
 		UIDatePicker _picker;
+		UIColor _defaultTextColor;
 
 		protected override void Dispose(bool disposing)
 		{
@@ -61,12 +62,15 @@ namespace Xamarin.Forms.Platform.iOS
 					entry.InputView = _picker;
 					entry.InputAccessoryView = toolbar;
 
+					_defaultTextColor = entry.TextColor;
+
 					_picker.ValueChanged += OnValueChanged;
 
 					SetNativeControl(entry);
 				}
 
 				UpdateTime();
+				UpdateTextColor();
 			}
 
 			base.OnElementChanged(e);
@@ -78,6 +82,9 @@ namespace Xamarin.Forms.Platform.iOS
 
 			if (e.PropertyName == TimePicker.TimeProperty.PropertyName || e.PropertyName == TimePicker.FormatProperty.PropertyName)
 				UpdateTime();
+
+			if (e.PropertyName == TimePicker.TextColorProperty.PropertyName || e.PropertyName == VisualElement.IsEnabledProperty.PropertyName)
+				UpdateTextColor();
 		}
 
 		void OnEnded(object sender, EventArgs eventArgs)
@@ -95,6 +102,16 @@ namespace Xamarin.Forms.Platform.iOS
 			((IElementController)Element).SetValueFromRenderer(TimePicker.TimeProperty, _picker.Date.ToDateTime() - new DateTime(1, 1, 1));
 		}
 
+		void UpdateTextColor()
+		{
+			var textColor = Element.TextColor;
+
+			if (textColor.IsDefault || !Element.IsEnabled)
+				Control.TextColor = _defaultTextColor;
+			else
+				Control.TextColor = textColor.ToUIColor();
+		}
+
 		void UpdateTime()
 		{
 			_picker.Date = new DateTime(1, 1, 1).Add(Element.Time).ToNSDate();