OptionGroup<T>.withLabel constructor

OptionGroup<T>.withLabel(
  1. List<T> items, [
  2. String? label,
  3. String? emptyLabel
])

An option group with a label is recommended when multiple option groups exist in a selection list.

Implementation

OptionGroup.withLabel(super.items, [super.label, String? emptyLabel])
    : _emptyLabelFcn = emptyLabel != null ? (() => emptyLabel) : null,
      super.withLabel();