BarBackgroundColor and BarTextColor on TabbedPage (#96)

* [Core] Add properties to TabbedPage

* [Controls] Add properties to test page

* [iOS] Added BarBackgroundColor & BarTextColor to TabbedPage

* [A] Added BarBackgroundColor & BarTextColor to TabbedPage

* [UWP] Added BarBackgroundColor & BarTextColor to TabbedPage

* [WinRT] Format file

* [WinRT] Added BarBackgroundColor & BarTextColor to TabbedPage

* [Docs] Updated docs

2 files changed, 57 insertions, 2 deletions

diff --git a/Xamarin.Forms.Platform.iOS/Renderers/NavigationRenderer.cs b/Xamarin.Forms.Platform.iOS/Renderers/NavigationRenderer.cs
index f09fec9a..da3a0aa2 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/NavigationRenderer.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/NavigationRenderer.cs
@@ -594,6 +594,8 @@ namespace Xamarin.Forms.Platform.iOS
 			{
 				var titleAttributes = new UIStringAttributes();
 				titleAttributes.Font = globalAttributes.Font;
+				// TODO: the ternary if statement here will always return false because of the encapsulating if statement.
+				// What was the intention?
 				titleAttributes.ForegroundColor = barTextColor == Color.Default
 					? titleAttributes.ForegroundColor ?? UINavigationBar.Appearance.TintColor
 					: barTextColor.ToUIColor();
@@ -640,7 +642,7 @@ namespace Xamarin.Forms.Platform.iOS
 				{
 					containerController.NavigationItem.LeftBarButtonItem =
 						new UIBarButtonItem(new UIImage(_parentMasterDetailPage.Master.Icon), UIBarButtonItemStyle.Plain,
-							(o, e) => _parentMasterDetailPage.IsPresented = !_parentMasterDetailPage.IsPresented);
+						(o, e) => _parentMasterDetailPage.IsPresented = !_parentMasterDetailPage.IsPresented);
 				}
 				catch (Exception)
 				{
diff --git a/Xamarin.Forms.Platform.iOS/Renderers/TabbedRenderer.cs b/Xamarin.Forms.Platform.iOS/Renderers/TabbedRenderer.cs
index 14bf4a24..2db8ac26 100644
--- a/Xamarin.Forms.Platform.iOS/Renderers/TabbedRenderer.cs
+++ b/Xamarin.Forms.Platform.iOS/Renderers/TabbedRenderer.cs
@@ -74,6 +74,9 @@ namespace Xamarin.Forms.Platform.iOS
 			//disable edit/reorder of tabs
 			CustomizableViewControllers = null;
 
+			UpdateBarBackgroundColor();
+			UpdateBarTextColor();
+
 			EffectUtilities.RegisterEffectControlProvider(this, oldElement, element);
 		}
 
@@ -227,7 +230,7 @@ namespace Xamarin.Forms.Platform.iOS
 
 		void OnPropertyChanged(object sender, PropertyChangedEventArgs e)
 		{
-			if (e.PropertyName == "CurrentPage")
+			if (e.PropertyName == nameof(TabbedPage.CurrentPage))
 			{
 				var current = Tabbed.CurrentPage;
 				if (current == null)
@@ -239,6 +242,10 @@ namespace Xamarin.Forms.Platform.iOS
 
 				SelectedViewController = controller;
 			}
+			else if (e.PropertyName == TabbedPage.BarBackgroundColorProperty.PropertyName)
+				UpdateBarBackgroundColor();
+			else if (e.PropertyName == TabbedPage.BarTextColorProperty.PropertyName)
+				UpdateBarTextColor();
 		}
 
 		void Reset()
@@ -292,6 +299,52 @@ namespace Xamarin.Forms.Platform.iOS
 			Platform.SetRenderer(page, null);
 		}
 
+		void UpdateBarBackgroundColor()
+		{
+			if (Tabbed == null || TabBar == null)
+				return;
+
+			var barBackgroundColor = Tabbed.BarBackgroundColor;
+
+			if (Forms.IsiOS7OrNewer)
+			{
+				TabBar.BarTintColor = barBackgroundColor == Color.Default ? UINavigationBar.Appearance.BarTintColor : barBackgroundColor.ToUIColor();
+			}
+			else
+			{
+				TabBar.TintColor = barBackgroundColor == Color.Default ? UINavigationBar.Appearance.TintColor : barBackgroundColor.ToUIColor();
+			}
+		}
+
+		void UpdateBarTextColor()
+		{
+			if (Tabbed == null || TabBar == null || TabBar.Items == null)
+				return;
+
+			var barTextColor = Tabbed.BarTextColor;
+
+			var globalAttributes = UINavigationBar.Appearance.GetTitleTextAttributes();
+
+			var attributes = new UITextAttributes { Font = globalAttributes.Font };
+
+			if (barTextColor == Color.Default)
+				attributes.TextColor = globalAttributes.TextColor;
+			else
+				attributes.TextColor = barTextColor.ToUIColor();
+
+			foreach (UITabBarItem item in TabBar.Items)
+			{
+				item.SetTitleTextAttributes(attributes, UIControlState.Normal);
+			}
+
+			// set TintColor for selected icon
+			// setting the unselected icon tint is not supported by iOS
+			if (Forms.IsiOS7OrNewer)
+			{
+				TabBar.TintColor = barTextColor == Color.Default ? UINavigationBar.Appearance.TintColor : barTextColor.ToUIColor();
+			}
+		}
+
 		void UpdateChildrenOrderIndex(UIViewController[] viewControllers)
 		{
 			for (var i = 0; i < viewControllers.Length; i++)