redirectFocusToFirstEmptyField property
Whether focus should jump to the first empty field when a later field gains focus.
Defaults to false: the user can tap any box and type into it, even if earlier boxes are still empty. When true, focusing a box beyond the first empty one redirects focus to the first empty box, so the code is always entered contiguously from the start.
Implementation
final bool redirectFocusToFirstEmptyField;