[iOS] Use UIButtonType.System for Button and utilize UIButton.Appearance (#554)

* Change button style and use UIButton appearance

* added sample code

* change references

* setting other properties

* add comment

* refactor proxy setter

* made control states array static

* remove category declaration

* changes

* add sample code

* changes

* Fix identation

* Update ButtonRenderer.cs

2 files changed, 114 insertions, 0 deletions

diff --git a/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla40251.cs b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla40251.cs
new file mode 100644
index 00000000..64e9f667
--- /dev/null
+++ b/Xamarin.Forms.Controls.Issues/Xamarin.Forms.Controls.Issues.Shared/Bugzilla40251.cs
@@ -0,0 +1,113 @@
+using Xamarin.Forms.CustomAttributes;
+using Xamarin.Forms.Internals;
+using System;
+
+#if UITEST
+using Xamarin.UITest;
+using NUnit.Framework;
+#endif
+
+namespace Xamarin.Forms.Controls.Issues
+{
+	[Preserve(AllMembers = true)]
+	[Issue(IssueTracker.Bugzilla, 40251, "Cannot style Buttons natively using UIButton.Appearance", PlatformAffected.iOS)]
+	public class Bugzilla40251 : TestNavigationPage // or TestMasterDetailPage, etc ...
+	{
+		protected override void Init()
+		{
+			PushAsync(new LandingPage40251());
+		}
+	}
+
+	[Preserve(AllMembers = true)]
+	public class LandingPage40251 : ContentPage
+	{
+		public LandingPage40251()
+		{
+			var stackLayout = new StackLayout
+			{
+				Orientation = StackOrientation.Vertical,
+				Spacing = 20,
+				VerticalOptions = LayoutOptions.Center
+			};
+
+			var label0 = new Label
+			{
+				Text = "Each label below will update UIButton.Appearance proxy. When you remove the page from the stack, the original value will be set again.",
+				HorizontalTextAlignment = TextAlignment.Center
+			};
+			stackLayout.Children.Add(label0);
+
+			var label1 = new Label
+			{
+				Text = "TitleColor",
+				HorizontalTextAlignment = TextAlignment.Center
+			};
+			var t1 = new TapGestureRecognizer();
+			t1.Tapped += T_Tapped;
+			label1.GestureRecognizers.Add(t1);
+			stackLayout.Children.Add(label1);
+
+			var label2 = new Label
+			{
+				Text = "TitleShadowColor",
+				HorizontalTextAlignment = TextAlignment.Center
+			};
+			var t2 = new TapGestureRecognizer();
+			t2.Tapped += T_Tapped2;
+			label2.GestureRecognizers.Add(t2);
+			stackLayout.Children.Add(label2);
+
+			var label3 = new Label
+			{
+				Text = "BackgroundImage",
+				HorizontalTextAlignment = TextAlignment.Center
+			};
+			var t3 = new TapGestureRecognizer();
+			t3.Tapped += T_Tapped3;
+			label3.GestureRecognizers.Add(t3);
+			stackLayout.Children.Add(label3);
+
+			Content = stackLayout;
+		}
+
+		private async void T_Tapped(object sender, EventArgs e)
+		{
+			await Navigation.PushAsync(new TestPage40251("TitleColor"));
+		}
+
+		private async void T_Tapped2(object sender, EventArgs e)
+		{
+			await Navigation.PushAsync(new TestPage40251("TitleShadowColor"));
+		}
+
+		private async void T_Tapped3(object sender, EventArgs e)
+		{
+			await Navigation.PushAsync(new TestPage40251("BackgroundImage"));
+		}
+	}
+
+	[Preserve(AllMembers = true)]
+	public class TestPage40251 : ContentPage
+	{
+		public static string Arg;
+
+		public TestPage40251(string arg)
+		{
+			Arg = arg;
+
+			Content = new ContentView
+			{
+				Content = new Button
+				{
+					HorizontalOptions = LayoutOptions.Center,
+					VerticalOptions = LayoutOptions.Center,
+					Text = "Button",
+					BackgroundColor = Color.Black,
+					WidthRequest = 250,
+					HeightRequest = 50
+				}
+			};
+		}
+	}
+}
\ No newline at end of file
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 23fc5381..d8b688dd 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
@@ -116,6 +116,7 @@
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla40173.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla39821.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla40185.cs" />
+    <Compile Include="$(MSBuildThisFileDirectory)Bugzilla40251.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla40333.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla31806.cs" />
     <Compile Include="$(MSBuildThisFileDirectory)Bugzilla40408.cs" />