Add Windows Share Target support for image files

Enable the app to receive images via the Windows Share UI by declaring share target support in the manifest and handling share activation. Shared images are copied to a temp folder and loaded automatically on launch. CLI argument loading is now secondary to share activation.

Author: TheJoeFin

Simple Icon File Maker/Simple Icon File Maker (Package)/Package.appxmanifest

@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="utf-8"?>
+<?xml version="1.0" encoding="utf-8"?>
 
 <Package
   xmlns="http://schemas.microsoft.com/appx/manifest/foundation/windows10"
@@ -57,6 +57,18 @@
             <uap:Logo>Images\Image128.png</uap:Logo>
           </uap:FileTypeAssociation>
         </uap:Extension>
+        <uap:Extension Category="windows.shareTarget">
+          <uap:ShareTarget>
+            <uap:SupportedFileTypes>
+              <uap:FileType>.png</uap:FileType>
+              <uap:FileType>.jpg</uap:FileType>
+              <uap:FileType>.jpeg</uap:FileType>
+              <uap:FileType>.bmp</uap:FileType>
+              <uap:FileType>.ico</uap:FileType>
+            </uap:SupportedFileTypes>
+            <uap:DataFormat>Bitmap</uap:DataFormat>
+          </uap:ShareTarget>
+        </uap:Extension>
       </Extensions>
     </Application>
   </Applications>

Simple Icon File Maker/Simple Icon File Maker/App.xaml.cs

@@ -1,12 +1,17 @@
 using Microsoft.Extensions.DependencyInjection;
 using Microsoft.Extensions.Hosting;
 using Microsoft.UI.Xaml;
+using Microsoft.Windows.AppLifecycle;
 using Simple_Icon_File_Maker.Activation;
 using Simple_Icon_File_Maker.Contracts.Services;
 using Simple_Icon_File_Maker.Models;
 using Simple_Icon_File_Maker.Services;
 using Simple_Icon_File_Maker.ViewModels;
 using Simple_Icon_File_Maker.Views;
+using Windows.ApplicationModel.DataTransfer;
+using Windows.ApplicationModel.DataTransfer.ShareTarget;
+using Windows.Storage;
+using Windows.Storage.Streams;
 
 namespace Simple_Icon_File_Maker;
 
@@ -37,6 +42,8 @@ public static T GetService<T>()
 
     public static UIElement? AppTitlebar { get; set; }
 
+    public static string? SharedImagePath { get; set; }
+
     public App()
     {
         InitializeComponent();
@@ -93,8 +100,63 @@ private void App_UnhandledException(object sender, Microsoft.UI.Xaml.UnhandledEx
     protected override async void OnLaunched(LaunchActivatedEventArgs args)
     {
         base.OnLaunched(args);
+
+        var activatedEventArgs = AppInstance.GetCurrent().GetActivatedEventArgs();
+        if (activatedEventArgs.Kind == ExtendedActivationKind.ShareTarget)
+        {
+            await HandleShareTargetActivationAsync(activatedEventArgs);
+        }
+
         await App.GetService<IActivationService>().ActivateAsync(args);
     }
 
+    private static async Task HandleShareTargetActivationAsync(AppActivationArguments activatedEventArgs)
+    {
+        if (activatedEventArgs.Data is Windows.ApplicationModel.Activation.IShareTargetActivatedEventArgs shareArgs)
+        {
+            ShareOperation shareOperation = shareArgs.ShareOperation;
+            shareOperation.ReportStarted();
+
+            try
+            {
+                if (shareOperation.Data.Contains(StandardDataFormats.StorageItems))
+                {
+                    IReadOnlyList<IStorageItem> items = await shareOperation.Data.GetStorageItemsAsync();
+                    foreach (IStorageItem item in items)
+                    {
+                        if (item is StorageFile file && Constants.FileTypes.SupportedImageFormats.Contains(file.FileType, StringComparer.OrdinalIgnoreCase))
+                        {
+                            StorageFolder tempFolder = ApplicationData.Current.TemporaryFolder;
+                            StorageFile copiedFile = await file.CopyAsync(tempFolder, file.Name, NameCollisionOption.GenerateUniqueName);
+                            SharedImagePath = copiedFile.Path;
+                            break;
+                        }
+                    }
+                }
+                else if (shareOperation.Data.Contains(StandardDataFormats.Bitmap))
+                {
+                    var bitmapRef = await shareOperation.Data.GetBitmapAsync();
+                    var stream = await bitmapRef.OpenReadAsync();
+
+                    StorageFolder tempFolder = ApplicationData.Current.TemporaryFolder;
+                    StorageFile tempFile = await tempFolder.CreateFileAsync("shared_image.png", CreationCollisionOption.GenerateUniqueName);
+
+                    using (var outputStream = await tempFile.OpenAsync(FileAccessMode.ReadWrite))
+                    {
+                        await RandomAccessStream.CopyAsync(stream, outputStream);
+                    }
+
+                    SharedImagePath = tempFile.Path;
+                }
+            }
+            catch (Exception)
+            {
+                // If share handling fails, continue with normal launch
+            }
+
+            shareOperation.ReportCompleted();
+        }
+    }
+
     public static string[]? cliArgs { get; } = Environment.GetCommandLineArgs();
 }

Simple Icon File Maker/Simple Icon File Maker/ViewModels/MainViewModel.cs

@@ -152,8 +152,14 @@ public async void OnNavigatedTo(object parameter)
 
         ShowUpgradeToProButton = !_storeService.OwnsPro;
 
+        // Load shared image path from share target activation
+        if (!string.IsNullOrEmpty(App.SharedImagePath))
+        {
+            ImagePath = App.SharedImagePath;
+            App.SharedImagePath = null;
+        }
         // Load CLI args if present
-        if (App.cliArgs?.Length > 1)
+        else if (App.cliArgs?.Length > 1)
         {
             ImagePath = App.cliArgs[1];
         }