Update DataGridColumn.cs

src/Avalonia.Controls.DataGrid/DataGridColumn.cs

@@ -653,6 +653,26 @@ namespace Avalonia.Controls
             return null;
         }
 
+        /// <summary>
+        /// Switches the current state of sort direction
+        /// </summary>
+        /// <param name="clear">Clear the current sort direction instead</param>
+        public void PerformSort(bool clear)
+        {
+            //InvokeProcessSort is already validating if sorting is possible
+            _headerCell?.InvokeProcessSort(clear ? Input.KeyModifiers.Control : Input.KeyModifiers.None);
+        }
+
+        /// <summary>
+        /// Changes the sort direction of this column
+        /// </summary>
+        /// <param name="direction">New sort direction</param>
+        public void PerformSort(ListSortDirection direction)
+        {
+            //InvokeProcessSort is already validating if sorting is possible
+            _headerCell?.InvokeProcessSort(Input.KeyModifiers.None, direction);
+        }
+
         /// <summary>
         /// When overridden in a derived class, causes the column cell being edited to revert to the unedited value.
         /// </summary>