fix share title on iOS

Xamarin.Essentials/Share/Share.ios.cs

@@ -2,6 +2,7 @@
 using System.Drawing;
 using System.Threading.Tasks;
 using Foundation;
+using LinkPresentation;
 using UIKit;
 
 namespace Xamarin.Essentials
@@ -14,12 +15,12 @@ static async Task PlatformRequestAsync(ShareTextRequest request)
             var items = new List<NSObject>();
             if (!string.IsNullOrWhiteSpace(request.Text))
             {
-                items.Add(new ShareActivityItemSource(new NSString(request.Text), request.Title));
+                items.Add(GetShareItem(new NSString(request.Text), request.Title));
             }
 
             if (!string.IsNullOrWhiteSpace(request.Uri))
             {
-                items.Add(new ShareActivityItemSource(NSUrl.FromString(request.Uri), request.Title));
+                items.Add(GetShareItem(NSUrl.FromString(request.Uri), request.Title));
             }
 
             var activityController = new UIActivityViewController(items.ToArray(), null)
@@ -50,14 +51,10 @@ static async Task PlatformRequestAsync(ShareMultipleFilesRequest request)
 
             var items = new List<NSObject>();
 
-            var hasTitel = !string.IsNullOrWhiteSpace(request.Title);
             foreach (var file in request.Files)
             {
                 var fileUrl = NSUrl.FromFilename(file.FullPath);
-                if (hasTitel)
-                    items.Add(new ShareActivityItemSource(fileUrl, request.Title)); // Share with title (subject)
-                else
-                    items.Add(fileUrl); // No title specified
+                items.Add(GetShareItem(fileUrl, request.Title));
             }
 
             var activityController = new UIActivityViewController(items.ToArray(), null)
@@ -81,23 +78,40 @@ static async Task PlatformRequestAsync(ShareMultipleFilesRequest request)
             await vc.PresentViewControllerAsync(activityController, true);
             await src.Task;
         }
+
+        static NSObject GetShareItem(NSString obj, string title)
+            => new ShareActivityItemSource(obj, string.IsNullOrWhiteSpace(title) ? obj : title);
+
+        static NSObject GetShareItem(NSObject obj, string title)
+            => string.IsNullOrWhiteSpace(title)
+                ? obj
+                : new ShareActivityItemSource(obj, title);
     }
 
     class ShareActivityItemSource : UIActivityItemSource
     {
         readonly NSObject item;
-        readonly string subject;
+        readonly string title;
 
-        internal ShareActivityItemSource(NSObject item, string subject)
+        internal ShareActivityItemSource(NSObject item, string title)
         {
             this.item = item;
-            this.subject = subject;
+            this.title = title;
         }
 
         public override NSObject GetItemForActivity(UIActivityViewController activityViewController, NSString activityType) => item;
 
         public override NSObject GetPlaceholderData(UIActivityViewController activityViewController) => item;
 
-        public override string GetSubjectForActivity(UIActivityViewController activityViewController, NSString activityType) => subject;
+        public override LPLinkMetadata GetLinkMetadata(UIActivityViewController activityViewController)
+        {
+            var meta = new LPLinkMetadata();
+            if (!string.IsNullOrWhiteSpace(title))
+                meta.Title = title;
+            if (item is NSUrl url)
+                meta.Url = url;
+
+            return meta;
+        }
     }
 }