feat: Added Post<T> to IDispatcher

src/Avalonia.Base/Threading/IDispatcher.cs

@@ -27,6 +27,15 @@ namespace Avalonia.Threading
         /// <returns>A task that can be used to track the method's execution.</returns>
         void Post(Action action, DispatcherPriority priority = DispatcherPriority.Normal);
 
+        /// <summary>
+        /// Invokes a method on the dispatcher thread.
+        /// </summary>
+        /// <typeparam name="T">type of argument</typeparam>
+        /// <param name="action">The method to call.</param>
+        /// <param name="arg">The argument of method to call.</param>
+        /// <param name="priority">The priority with which to invoke the method.</param>
+        void Post<T>(Action<T> action, T arg, DispatcherPriority priority = DispatcherPriority.Normal);
+
         /// <summary>
         /// Posts an action that will be invoked on the dispatcher thread.
         /// </summary>
@@ -59,4 +68,4 @@ namespace Avalonia.Threading
         /// <returns>A task that represents a proxy for the task returned by <paramref name="function"/>.</returns>
         Task<TResult> InvokeAsync<TResult>(Func<Task<TResult>> function, DispatcherPriority priority = DispatcherPriority.Normal);
     }
-}
+}