Merge pull request #1172 from dalexsoto/alex-WebAuthenticator

[WebAuthenticator] Break iOS 13 dependency on WebAuthenticator
xamarin · Mar 26, 2020 · 351d96d · 351d96d
2 parents 34cc39b + 743c959
commit 351d96d
Showing 1 changed file with 17 additions and 2 deletions.
diff --git a/Xamarin.Essentials/WebAuthenticator/WebAuthenticator.ios.tvos.cs b/Xamarin.Essentials/WebAuthenticator/WebAuthenticator.ios.tvos.cs
@@ -14,6 +14,13 @@ namespace Xamarin.Essentials
 {
     public static partial class WebAuthenticator
     {
+#if __IOS__
+        [System.Runtime.InteropServices.DllImport(ObjCRuntime.Constants.ObjectiveCLibrary, EntryPoint = "objc_msgSend")]
+        [System.Diagnostics.CodeAnalysis.SuppressMessage("Style", "IDE1006:Naming Styles", Justification = "Required for iOS Export")]
+        [System.Diagnostics.CodeAnalysis.SuppressMessage("StyleCop.CSharp.NamingRules", "SA1300:Element should begin with upper-case letter", Justification = "Required for iOS Export")]
+        static extern void void_objc_msgSend_IntPtr(IntPtr receiver, IntPtr selector, IntPtr arg1);
+#endif
+
         static TaskCompletionSource<WebAuthenticatorResult> tcsResponse;
         static UIViewController currentViewController;
         static Uri redirectUri;
@@ -49,7 +56,13 @@ void AuthSessionCallback(NSUrl cbUrl, NSError error)
                 if (UIDevice.CurrentDevice.CheckSystemVersion(12, 0))
                 {
                     var was = new ASWebAuthenticationSession(new NSUrl(url.OriginalString), scheme, AuthSessionCallback);
-                    was.PresentationContextProvider = new ContextProvider(Platform.GetCurrentWindow());
+
+                    if (UIDevice.CurrentDevice.CheckSystemVersion(13, 0))
+                    {
+                        var ctx = new ContextProvider(Platform.GetCurrentWindow());
+                        void_objc_msgSend_IntPtr(was.Handle, ObjCRuntime.Selector.GetHandle("setPresentationContextProvider:"), ctx.Handle);
+                    }
+
                     was.Start();
                     return await tcsResponse.Task;
                 }
@@ -175,13 +188,15 @@ public override void DidFinish(SFSafariViewController controller) =>
                 DidFinishHandler?.Invoke(controller);
         }
 
-        class ContextProvider : NSObject, IASWebAuthenticationPresentationContextProviding
+        [ObjCRuntime.Adopts("ASWebAuthenticationPresentationContextProviding")]
+        class ContextProvider : NSObject
         {
             public ContextProvider(UIWindow window) =>
                 Window = window;
 
             public UIWindow Window { get; private set; }
 
+            [Export("presentationAnchorForWebAuthenticationSession:")]
             public UIWindow GetPresentationAnchor(ASWebAuthenticationSession session)
                 => Window;
         }