Add first event with a key value

Toolkit.Foundation/Activate.cs

@@ -5,4 +5,8 @@ public record Activate
     public static ActivateEventArgs<TValue> As<TValue>(TValue value) => new(value);
 
     public static ActivateEventArgs<TValue> As<TValue>() where TValue : new() => new(new TValue());
+
+    public static ActivateEventArgs<TKey, TValue> As<TKey, TValue>(TValue value) => new(value);
+
+    public static ActivateEventArgs<TKey, TValue> As<TKey, TValue>() where TValue : new() => new(new TValue());
 }

Toolkit.Foundation/ActivateEventArgs.cs

@@ -14,3 +14,18 @@ public record ActivateEventArgs<TValue>
 
     }
 }
+
+public record ActivateEventArgs<TKey, TValue>
+{
+    public TValue? Value { get; }
+
+    public ActivateEventArgs(TValue value)
+    {
+        Value = value;
+    }
+
+    public ActivateEventArgs()
+    {
+
+    }
+}