Improving the operation of PresentationControllers (#1846)

Co-authored-by: Matthew Leibowitz <mattleibow@live.com>

Author: dimonovdd

Xamarin.Essentials/Contacts/Contacts.ios.macos.cs

@@ -39,6 +39,14 @@ static Task<Contact> PlatformPickContactAsync()
                 })
             };
 
+            if (picker.PresentationController != null)
+            {
+                picker.PresentationController.Delegate = new Platform.UIPresentationControllerDelegate
+                {
+                    DismissHandler = () => source?.TrySetResult(null)
+                };
+            }
+
             uiView.PresentViewController(picker, true, null);
 
             return source.Task;

Xamarin.Essentials/Email/Email.ios.cs

@@ -1,4 +1,5 @@
-using System.IO;
+using System;
+using System.IO;
 using System.Threading.Tasks;
 using Foundation;
 using MessageUI;
@@ -50,13 +51,21 @@ static Task ComposeWithMailCompose(EmailMessage message)
                 }
             }
 
-            // show the controller
             var tcs = new TaskCompletionSource<bool>();
             controller.Finished += (sender, e) =>
             {
                 controller.DismissViewController(true, null);
                 tcs.TrySetResult(e.Result == MFMailComposeResult.Sent);
             };
+
+            if (controller.PresentationController != null)
+            {
+                controller.PresentationController.Delegate = new Platform.UIPresentationControllerDelegate
+                {
+                    DismissHandler = () => tcs.TrySetResult(false)
+                };
+            }
+
             parentController.PresentViewController(controller, true, null);
 
             return tcs.Task;

Xamarin.Essentials/FilePicker/FilePicker.ios.cs

@@ -34,9 +34,9 @@ static async Task<IEnumerable<FileResult>> PlatformPickAsync(PickOptions options
 
             if (documentPicker.PresentationController != null)
             {
-                documentPicker.PresentationController.Delegate = new PickerPresentationControllerDelegate
+                documentPicker.PresentationController.Delegate = new Platform.UIPresentationControllerDelegate
                 {
-                    PickHandler = urls => GetFileResults(urls, tcs)
+                    DismissHandler = () => GetFileResults(null, tcs)
                 };
             }
 
@@ -74,14 +74,6 @@ public override void DidPickDocument(UIDocumentPickerViewController controller,
             public override void DidPickDocument(UIDocumentPickerViewController controller, NSUrl url)
                 => PickHandler?.Invoke(new NSUrl[] { url });
         }
-
-        class PickerPresentationControllerDelegate : UIAdaptivePresentationControllerDelegate
-        {
-            public Action<NSUrl[]> PickHandler { get; set; }
-
-            public override void DidDismiss(UIPresentationController presentationController) =>
-                PickHandler?.Invoke(null);
-        }
     }
 
     public partial class FilePickerFileType

Xamarin.Essentials/MediaPicker/MediaPicker.ios.cs

@@ -75,9 +75,9 @@ static async Task<FileResult> PhotoAsync(MediaPickerOptions options, bool photo,
 
             if (picker.PresentationController != null)
             {
-                picker.PresentationController.Delegate = new PhotoPickerPresentationControllerDelegate
+                picker.PresentationController.Delegate = new Platform.UIPresentationControllerDelegate
                 {
-                    CompletedHandler = info => GetFileResult(info, tcs)
+                    DismissHandler = () => GetFileResult(null, tcs)
                 };
             }
 
@@ -167,13 +167,5 @@ public override void FinishedPickingMedia(UIImagePickerController picker, NSDict
             public override void Canceled(UIImagePickerController picker) =>
                 CompletedHandler?.Invoke(null);
         }
-
-        class PhotoPickerPresentationControllerDelegate : UIAdaptivePresentationControllerDelegate
-        {
-            public Action<NSDictionary> CompletedHandler { get; set; }
-
-            public override void DidDismiss(UIPresentationController presentationController) =>
-                CompletedHandler?.Invoke(null);
-        }
     }
 }

Xamarin.Essentials/Platform/Platform.ios.tvos.watchos.cs

@@ -73,12 +73,20 @@ internal static bool HasOSVersion(int major, int minor) =>
 
 #if __IOS__ || __TVOS__
 
+        static Func<UIViewController> getCurrentController;
+
+        public static void Init(Func<UIViewController> getCurrentUIViewController)
+            => getCurrentController = getCurrentUIViewController;
+
         public static UIViewController GetCurrentUIViewController() =>
             GetCurrentViewController(false);
 
         internal static UIViewController GetCurrentViewController(bool throwIfNull = true)
         {
-            UIViewController viewController = null;
+            var viewController = getCurrentController?.Invoke();
+
+            if (viewController != null)
+                return viewController;
 
             var window = UIApplication.SharedApplication.KeyWindow;
 
@@ -138,5 +146,24 @@ internal static UIWindow GetCurrentWindow(bool throwIfNull = true)
 
         internal static NSOperationQueue GetCurrentQueue() =>
             NSOperationQueue.CurrentQueue ?? new NSOperationQueue();
+
+#if __IOS__
+        internal class UIPresentationControllerDelegate : UIAdaptivePresentationControllerDelegate
+        {
+            public Action DismissHandler { get; set; }
+
+            public override void DidDismiss(UIPresentationController presentationController)
+            {
+                DismissHandler?.Invoke();
+                DismissHandler = null;
+            }
+
+            protected override void Dispose(bool disposing)
+            {
+                DismissHandler?.Invoke();
+                base.Dispose(disposing);
+            }
+        }
+#endif
     }
 }

Xamarin.Essentials/Sms/Sms.ios.cs

@@ -21,13 +21,21 @@ static Task PlatformComposeAsync(SmsMessage message)
 
             messageController.Recipients = message?.Recipients?.ToArray() ?? new string[] { };
 
-            // show the controller
             var tcs = new TaskCompletionSource<bool>();
             messageController.Finished += (sender, e) =>
             {
                 messageController.DismissViewController(true, null);
                 tcs?.TrySetResult(e.Result == MessageComposeResult.Sent);
             };
+
+            if (controller.PresentationController != null)
+            {
+                controller.PresentationController.Delegate = new Platform.UIPresentationControllerDelegate
+                {
+                    DismissHandler = () => tcs.TrySetResult(false)
+                };
+            }
+
             controller.PresentViewController(messageController, true, null);
 
             return tcs.Task;