From e3d400c7679179f90dad333464c2f0832250322d Mon Sep 17 00:00:00 2001
From: Chris Pulman <chris.pulman@yahoo.com>
Date: Thu, 7 Nov 2024 00:09:24 +0000
Subject: [PATCH] FIx For IViewFor with Generic Class

---
 README.md                                       | 17 +++++++++++++++++
 .../AttributeDefinitions.cs                     | 12 ++++++++++++
 .../IViewFor/IViewForGenerator.Execute.cs       |  4 +++-
 3 files changed, 32 insertions(+), 1 deletion(-)

diff --git a/README.md b/README.md
index 969ee24..b7c2641 100644
--- a/README.md
+++ b/README.md
@@ -389,6 +389,23 @@ The class must inherit from a UI Control from any of the following platforms and
 - Avalonia (Avalonia)
 - Uno (Windows.UI.Xaml).
 
+### Usage IViewFor with ViewModel Name - Generic Types should be used with the fully qualified name, otherwise use nameof(ViewModelTypeName)
+```csharp
+using ReactiveUI.SourceGenerators;
+
+[IViewFor("MyReactiveGenericClass<int>")]
+public partial class MyReactiveControl : UserControl
+{
+    public MyReactiveControl()
+    {
+        InitializeComponent();
+        MyReactiveClass = new MyReactiveClass();
+    }
+}
+```
+
+### Usage IViewFor with ViewModel Type
+
 ```csharp
 using ReactiveUI.SourceGenerators;
 
diff --git a/src/ReactiveUI.SourceGenerators/AttributeDefinitions.cs b/src/ReactiveUI.SourceGenerators/AttributeDefinitions.cs
index 09903fa..418bd0c 100644
--- a/src/ReactiveUI.SourceGenerators/AttributeDefinitions.cs
+++ b/src/ReactiveUI.SourceGenerators/AttributeDefinitions.cs
@@ -207,6 +207,18 @@ namespace ReactiveUI.SourceGenerators;
 [global::System.CodeDom.Compiler.GeneratedCode("ReactiveUI.SourceGenerators.IViewForGenerator", "1.1.0.0")]
 [AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = false)]
 internal sealed class IViewForAttribute<T> : Attribute;
+
+/// <summary>
+/// IViewForAttribute.
+/// </summary>
+/// <seealso cref="System.Attribute" />
+/// <remarks>
+/// Initializes a new instance of the <see cref="IViewForAttribute"/> class.
+/// </remarks>
+/// <param name="viewModelType">Type of the view model.</param>
+[global::System.CodeDom.Compiler.GeneratedCode("ReactiveUI.SourceGenerators.IViewForGenerator", "1.1.0.0")]
+[AttributeUsage(AttributeTargets.Class, AllowMultiple = false, Inherited = false)]
+internal sealed class IViewForAttribute(string? viewModelType) : Attribute;
 #nullable restore
 #pragma warning restore
 """;
diff --git a/src/ReactiveUI.SourceGenerators/IViewFor/IViewForGenerator.Execute.cs b/src/ReactiveUI.SourceGenerators/IViewFor/IViewForGenerator.Execute.cs
index 0422d07..b48a957 100644
--- a/src/ReactiveUI.SourceGenerators/IViewFor/IViewForGenerator.Execute.cs
+++ b/src/ReactiveUI.SourceGenerators/IViewFor/IViewForGenerator.Execute.cs
@@ -50,9 +50,11 @@ public partial class IViewForGenerator
 
         token.ThrowIfCancellationRequested();
 
+        var constructorArgument = attributeData.GetConstructorArguments<string>().FirstOrDefault();
         var genericArgument = attributeData.GetGenericType();
         token.ThrowIfCancellationRequested();
-        if (!(genericArgument is string viewModelTypeName && viewModelTypeName.Length > 0))
+        var viewModelTypeName = string.IsNullOrWhiteSpace(constructorArgument) ? genericArgument : constructorArgument;
+        if (string.IsNullOrWhiteSpace(viewModelTypeName))
         {
             return default;
         }