items property
The list of items the user can select.
If the onChanged callback is null or the list of items is null then the dropdown button will be disabled, i.e. its arrow will be displayed in grey and it will not respond to input. A disabled button will display the disabledHint widget if it is non-null.
If decoration.hint
and variations is non-null and disabledHint is null,
the decoration.hint
widget will be displayed instead.
Implementation
final List<DropdownMenuItem<T>> items;