[release/8.0] [Blazor] Blazor InputRadio is broken by IHandleEvent

src/Components/Web/src/Forms/IInputRadioValueProvider.cs

@@ -0,0 +1,9 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.AspNetCore.Components;
+
+internal interface IInputRadioValueProvider
+{
+    public object? CurrentValue { get; }
+}

src/Components/Web/src/Forms/InputRadioContext.cs

@@ -8,21 +8,19 @@ namespace Microsoft.AspNetCore.Components.Forms;
 /// </summary>
 internal sealed class InputRadioContext
 {
+    private readonly IInputRadioValueProvider _valueProvider;
+
     public InputRadioContext? ParentContext { get; }
     public EventCallback<ChangeEventArgs> ChangeEventCallback { get; }
+    public object? CurrentValue => _valueProvider.CurrentValue;
 
     // Mutable properties that may change any time an InputRadioGroup is rendered
     public string? GroupName { get; set; }
-    public object? CurrentValue { get; set; }
     public string? FieldClass { get; set; }
 
-    /// <summary>
-    /// Instantiates a new <see cref="InputRadioContext" />.
-    /// </summary>
-    /// <param name="parentContext">The parent context, if any.</param>
-    /// <param name="changeEventCallback">The event callback to be invoked when the selected value is changed.</param>
-    public InputRadioContext(InputRadioContext? parentContext, EventCallback<ChangeEventArgs> changeEventCallback)
+    public InputRadioContext(IInputRadioValueProvider valueProvider, InputRadioContext? parentContext, EventCallback<ChangeEventArgs> changeEventCallback)
     {
+        _valueProvider = valueProvider;
         ParentContext = parentContext;
         ChangeEventCallback = changeEventCallback;
     }

src/Components/Web/src/Forms/InputRadioGroup.cs

@@ -10,7 +10,7 @@ namespace Microsoft.AspNetCore.Components.Forms;
 /// <summary>
 /// Groups child <see cref="InputRadio{TValue}"/> components.
 /// </summary>
-public class InputRadioGroup<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] TValue> : InputBase<TValue>
+public class InputRadioGroup<[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.All)] TValue> : InputBase<TValue>, IInputRadioValueProvider
 {
     private readonly string _defaultGroupName = Guid.NewGuid().ToString("N");
     private InputRadioContext? _context;
@@ -27,14 +27,16 @@ public class InputRadioGroup<[DynamicallyAccessedMembers(DynamicallyAccessedMemb
 
     [CascadingParameter] private InputRadioContext? CascadedContext { get; set; }
 
+    object? IInputRadioValueProvider.CurrentValue => CurrentValue;
+
     /// <inheritdoc />
     protected override void OnParametersSet()
     {
         // On the first render, we can instantiate the InputRadioContext
         if (_context is null)
         {
             var changeEventCallback = EventCallback.Factory.CreateBinder<string?>(this, __value => CurrentValueAsString = __value, CurrentValueAsString);
-            _context = new InputRadioContext(CascadedContext, changeEventCallback);
+            _context = new InputRadioContext(this, CascadedContext, changeEventCallback);
         }
         else if (_context.ParentContext != CascadedContext)
         {
@@ -59,7 +61,7 @@ protected override void OnParametersSet()
             // Otherwise, just use a GUID to disambiguate this group's radio inputs from any others on the page.
             _context.GroupName = _defaultGroupName;
         }
-        _context.CurrentValue = CurrentValue;
+
         _context.FieldClass = EditContext?.FieldCssClass(FieldIdentifier);
     }
 

src/Components/test/E2ETest/Tests/FormsTest.cs

@@ -844,6 +844,30 @@ public void InputRadioGroupWorksWithMutatingSetter()
         Browser.Equal("False", () => tuesday.GetDomProperty("checked"));
     }
 
+    [Theory]
+    [InlineData(0)]
+    [InlineData(2)]
+    public void InputRadioGroupWorksWithParentImplementingIHandleEvent(int n)
+    {
+        Browser.Url = new UriBuilder(Browser.Url) { Query = ($"?n={n}") }.ToString();
+        var appElement = Browser.MountTestComponent<InputRadioParentImplementsIHandleEvent>();
+        var zero = appElement.FindElement(By.Id("inputradiogroup-parent-ihandle-event-0"));
+        var one = appElement.FindElement(By.Id("inputradiogroup-parent-ihandle-event-1"));
+
+        Browser.Equal(n == 0 ? "True" : "False", () => zero.GetDomProperty("checked"));
+        Browser.Equal("False", () => one.GetDomProperty("checked"));
+
+        // Observe the changes after a click
+        one.Click();
+        Browser.Equal("False", () => zero.GetDomProperty("checked"));
+        Browser.Equal("True", () => one.GetDomProperty("checked"));
+
+        // Ensure other options can be selected
+        zero.Click();
+        Browser.Equal("False", () => one.GetDomProperty("checked"));
+        Browser.Equal("True", () => zero.GetDomProperty("checked"));
+    }
+
     [Fact]
     public void InputSelectWorksWithMutatingSetter()
     {

src/Components/test/testassets/BasicTestApp/FormsTest/InputRadioParentImplementsIHandleEvent.razor

@@ -0,0 +1,14 @@
+@using Microsoft.AspNetCore.Components.Forms
+@implements IHandleEvent
+
+<InputRadioGroup @bind-Value="N">
+  <InputRadio id="inputradiogroup-parent-ihandle-event-0" Value="0" />
+  <InputRadio id="inputradiogroup-parent-ihandle-event-1" Value="1" />
+</InputRadioGroup>
+
+@code {
+
+  [SupplyParameterFromQuery(Name = "n")] int? N { get; set; }
+
+  Task IHandleEvent.HandleEventAsync(EventCallbackWorkItem callback, object arg) => callback.InvokeAsync(arg);
+}

src/Components/test/testassets/BasicTestApp/Index.razor

@@ -49,6 +49,7 @@
         <option value="BasicTestApp.FormsTest.InputRangeComponent">Input range</option>
         <option value="BasicTestApp.FormsTest.InputsWithoutEditForm">Inputs without EditForm</option>
         <option value="BasicTestApp.FormsTest.InputsWithMutatingSetters">Inputs with mutating setters</option>
+        <option value="BasicTestApp.FormsTest.InputRadioParentImplementsIHandleEvent">Input Radio Parent Implements IHandleEvent</option>
         <option value="BasicTestApp.NavigateOnSubmit">Navigate to submit</option>
         <option value="BasicTestApp.GlobalizationBindCases">Globalization Bind Cases</option>
         <option value="BasicTestApp.GracefulTermination">Graceful Termination</option>