dragSpace property
The spacing between each drag.
If there are two items in the reactions list then dragSpace is the gap between the two items. Eg: If there is dragSpace of 40.0 then after dragging 40px from the first item, the next item will be focused. Similarly after dragging 40px from second item, the third item will be focused and so on.
The dragSpace parameter must not be null.
Implementation
final double dragSpace;