drag method Null safety

Drag drag(
  1. DragStartDetails details,
  2. VoidCallback dragCancelCallback
)

Start a drag activity corresponding to the given DragStartDetails.

The onDragCanceled argument will be invoked if the drag is ended prematurely (e.g. from another activity taking over). See ScrollDragController.onDragCanceled for details.

Implementation

Drag drag(DragStartDetails details, VoidCallback dragCancelCallback);