[Android] Fix TryGetFileFromPathAsync/TryGetFolderFromPathAsync returning null for content:// URI (#21986)

* [Android] Fix TryGetFileFromPathAsync/TryGetFolderFromPathAsync returning null for content:// URI

* [Android] Add URI scheme constants in AndroidStorageProvider

Directory.Packages.props

@@ -69,6 +69,7 @@
     <PackageVersion Include="Tmds.DBus.Generator" Version="0.94.1" />
     <PackageVersion Include="Xamarin.AndroidX.AppCompat" Version="1.7.1.3" />
     <PackageVersion Include="Xamarin.AndroidX.Core.SplashScreen" Version="1.2.0.2" />
+    <PackageVersion Include="Xamarin.AndroidX.DocumentFile" Version="1.1.0.3" />
     <PackageVersion Include="Xamarin.AndroidX.Window" Version="1.5.1.2" />
     <PackageVersion Include="xunit.runner.visualstudio" Version="3.1.5" />
     <PackageVersion Include="Xunit.StaFact" Version="3.0.13" />

src/Android/Avalonia.Android/Avalonia.Android.csproj

@@ -12,6 +12,7 @@
     <ProjectReference Include="..\..\..\packages\Avalonia\Avalonia.csproj" />
     <PackageReference Include="Xamarin.AndroidX.AppCompat" />
     <PackageReference Include="Xamarin.AndroidX.Window" />
+    <PackageReference Include="Xamarin.AndroidX.DocumentFile" />
   </ItemGroup>
   <ItemGroup>
     <ProjectReference Include="..\..\Avalonia.Base\Avalonia.Base.csproj" />

src/Android/Avalonia.Android/Platform/Storage/AndroidStorageProvider.cs

@@ -7,6 +7,7 @@ using Android;
 using Android.App;
 using Android.Content;
 using Android.Provider;
+using AndroidX.DocumentFile.Provider;
 using Avalonia.Platform.Storage;
 using Avalonia.Platform.Storage.FileIO;
 using AndroidUri = Android.Net.Uri;
@@ -18,6 +19,8 @@ namespace Avalonia.Android.Platform.Storage;
 internal class AndroidStorageProvider : IStorageProvider
 {
     public static ReadOnlySpan<byte> AndroidKey => "android"u8;
+    private const string ContentUriScheme = "content";
+    private const string FileUriScheme = "file";
     private readonly Activity _activity;
 
     public AndroidStorageProvider(Activity activity)
@@ -62,10 +65,29 @@ internal class AndroidStorageProvider : IStorageProvider
         //     to read or write files in your application-specific directories [...]"
         // Consequently, we don't try to check for that permission here anymore.
 
-        var javaFile = new JavaFile(androidUriPath);
-        if (javaFile.Exists() && javaFile.IsFile)
+        if (filePath.Scheme == FileUriScheme && androidUri.Path is not null)
         {
-            return new BclStorageFile(new System.IO.FileInfo(javaFile.AbsolutePath));
+            var javaFile = new JavaFile(androidUri.Path);
+            if (javaFile.Exists() && javaFile.IsFile)
+            {
+                return new BclStorageFile(new System.IO.FileInfo(javaFile.AbsolutePath));
+            }
+            return null;
+        }
+        else if (filePath.Scheme == ContentUriScheme && _activity.ContentResolver is not null)
+        {
+            try
+            {
+                using var stream = _activity.ContentResolver.OpenInputStream(androidUri);
+                if (stream is not null)
+                {
+                    return new AndroidStorageFile(_activity, androidUri);
+                }
+            }
+            catch (Exception)
+            {
+                return null;
+            }
         }
 
         return null;
@@ -89,10 +111,43 @@ internal class AndroidStorageProvider : IStorageProvider
             return null;
         }
 
-        var javaFile = new JavaFile(androidUriPath);
-        if (javaFile.Exists() && javaFile.IsDirectory)
+        if (folderPath.Scheme == FileUriScheme && androidUri.Path is not null)
+        {
+            var javaFile = new JavaFile(androidUri.Path);
+            if (javaFile.Exists() && javaFile.IsDirectory)
+            {
+                return new BclStorageFolder(new System.IO.DirectoryInfo(javaFile.AbsolutePath));
+            }
+            return null;
+        }
+        else if (folderPath.Scheme == ContentUriScheme)
         {
-            return new BclStorageFolder(new System.IO.DirectoryInfo(javaFile.AbsolutePath));
+            try
+            {
+                if (OperatingSystem.IsAndroidVersionAtLeast(21))
+                {
+                    if (DocumentsContract.IsTreeUri(androidUri))
+                    {
+                        var docId = DocumentsContract.GetTreeDocumentId(androidUri);
+                        if (!string.IsNullOrEmpty(docId))
+                        {
+                            return new AndroidStorageFolder(_activity, androidUri, false);
+                        }
+                    }
+                    else
+                    {
+                        var documentFile = DocumentFile.FromSingleUri(_activity, androidUri);
+                        if (documentFile is not null && documentFile.Exists() && documentFile.IsDirectory)
+                        {
+                            return new AndroidStorageFolder(_activity, androidUri, false);
+                        }
+                    }
+                }
+            }
+            catch (Exception)
+            {
+                return null;
+            }
         }
 
         return null;