[Enhancement][Launcher][iOS] ability to set PresentationSourceBounds (#1637)

Fixes #1611

Co-authored-by: Matthew Leibowitz <[email protected]>

Author: dimonovdd

Samples/Samples/View/LauncherPage.xaml

@@ -35,8 +35,8 @@
                     <Label Text="File Contents:" />
                     <Editor Text="{Binding FileAttachmentContents}" AutoSize="TextChanges" />
 
-                    <Button Text="Open File" Command="{Binding LaunchFileCommand}" />
-
+                    <Button Text="Open File" Command="{Binding LaunchFileCommand}"
+                            CommandParameter="{Binding Source={RelativeSource Self}}" />
                 </StackLayout>
             </Grid>
         </ScrollView>

Samples/Samples/ViewModel/LauncherViewModel.cs

@@ -1,6 +1,7 @@
 using System;
 using System.IO;
 using System.Windows.Input;
+using Samples.Helpers;
 using Xamarin.Essentials;
 using Xamarin.Forms;
 
@@ -29,7 +30,7 @@ public LauncherViewModel()
             LaunchMailCommand = new Command(OnLaunchMail);
             LaunchBrowserCommand = new Command(OnLaunchBrowser);
             CanLaunchCommand = new Command(CanLaunch);
-            LaunchFileCommand = new Command(OnFileRequest);
+            LaunchFileCommand = new Command<Xamarin.Forms.View>(OnFileRequest);
         }
 
         public string FileAttachmentContents
@@ -79,7 +80,7 @@ async void CanLaunch()
             }
         }
 
-        async void OnFileRequest()
+        async void OnFileRequest(Xamarin.Forms.View element)
         {
             if (!string.IsNullOrWhiteSpace(FileAttachmentContents))
             {
@@ -88,9 +89,12 @@ async void OnFileRequest()
                 var file = Path.Combine(FileSystem.CacheDirectory, fn);
                 File.WriteAllText(file, FileAttachmentContents);
 
+                var rect = element.GetAbsoluteBounds().ToSystemRectangle();
+                rect.Y += 40;
                 await Launcher.OpenAsync(new OpenFileRequest
                 {
-                    File = new ReadOnlyFile(file)
+                    File = new ReadOnlyFile(file),
+                    PresentationSourceBounds = rect
                 });
             }
         }

Xamarin.Essentials/Launcher/Launcher.ios.tvos.cs

@@ -1,5 +1,6 @@
 using System;
 using System.Diagnostics;
+using System.Drawing;
 using System.Threading.Tasks;
 using CoreGraphics;
 using Foundation;
@@ -43,9 +44,19 @@ static Task PlatformOpenAsync(OpenFileRequest request)
             };
 
             var view = Platform.GetCurrentUIViewController().View;
-            var rect = DeviceInfo.Idiom == DeviceIdiom.Tablet
-                ? new CGRect(new CGPoint(view.Bounds.Width / 2, view.Bounds.Height), CGRect.Empty.Size)
-                : view.Bounds;
+
+            CGRect rect;
+
+            if (request.PresentationSourceBounds != Rectangle.Empty)
+            {
+                rect = request.PresentationSourceBounds.ToPlatformRectangle();
+            }
+            else
+            {
+                rect = DeviceInfo.Idiom == DeviceIdiom.Tablet
+                    ? new CGRect(new CGPoint(view.Bounds.Width / 2, view.Bounds.Height), CGRect.Empty.Size)
+                    : view.Bounds;
+            }
 
             documentController.PresentOpenInMenu(rect, view, true);
             return Task.CompletedTask;

Xamarin.Essentials/Launcher/Launcher.shared.cs

@@ -1,6 +1,8 @@
 using System;
-using System.IO;
 using System.Threading.Tasks;
+#if !NETSTANDARD1_0
+using System.Drawing;
+#endif
 
 namespace Xamarin.Essentials
 {
@@ -86,5 +88,9 @@ public OpenFileRequest(string title, FileBase file)
         public string Title { get; set; }
 
         public ReadOnlyFile File { get; set; }
+
+#if !NETSTANDARD1_0
+        public Rectangle PresentationSourceBounds { get; set; } = Rectangle.Empty;
+#endif
     }
 }

docs/en/Xamarin.Essentials/OpenFileRequest.xml

@@ -106,5 +106,23 @@
         <remarks></remarks>
       </Docs>
     </Member>
+    <Member MemberName="PresentationSourceBounds">
+      <MemberSignature Language="C#" Value="public System.Drawing.Rectangle PresentationSourceBounds { get; set; }" />
+      <MemberSignature Language="ILAsm" Value=".property instance valuetype System.Drawing.Rectangle PresentationSourceBounds" />
+      <MemberSignature Language="DocId" Value="P:Xamarin.Essentials.ShareRequestBase.PresentationSourceBounds" />
+      <MemberType>Property</MemberType>
+      <AssemblyInfo>
+        <AssemblyName>Xamarin.Essentials</AssemblyName>
+        <AssemblyVersion>1.0.0.0</AssemblyVersion>
+      </AssemblyInfo>
+      <ReturnValue>
+        <ReturnType>System.Drawing.Rectangle</ReturnType>
+      </ReturnValue>
+      <Docs>
+        <summary>Gets or sets the source rectangle to display the Share UI from.</summary>
+        <value></value>
+        <remarks>This is only used on iOS currently.</remarks>
+      </Docs>
+    </Member>
   </Members>
 </Type>