onDragUpdate method
Implementation
void onDragUpdate(DragUpdateDetails details)
{
if (details.globalPosition.dx < last) swiping = false;
if (swiping) last = details.globalPosition.dx;
}
void onDragUpdate(DragUpdateDetails details)
{
if (details.globalPosition.dx < last) swiping = false;
if (swiping) last = details.globalPosition.dx;
}