focusNodes property Null safety
The list of
FocusNodes, corresponding to each toggle button.
Focus is used to determine which widget should be affected by keyboard events. The focus tree keeps track of which widget is currently focused on by the user.
If not null, the length of focusNodes has to match the length of children.
FocusNode for more information about how focus nodes are used.
final List<FocusNode>? focusNodes;