createRecognizer method
Provides the gesture recognizer used to indicate the start of a reordering drag operation.
By default this returns an ImmediateMultiDragGestureRecognizer but subclasses can use this to customize the drag start gesture.
Implementation
@protected
MultiDragGestureRecognizer createRecognizer() {
return ImmediateMultiDragGestureRecognizer(debugOwner: this);
}