decrementIndex method

FormIndex decrementIndex(
  1. FormIndex index
)

The index before index.

Implementation

FormIndex decrementIndex(FormIndex index) {
  final indexes = <int>[];
  final multiplicities = <int>[];
  final elements = <FormElement>[];
  if (index.isBeginningOfFormIndex) return index;
  if (index.isEndOfFormIndex) {
    if (form.children.isEmpty) return FormIndex.beginningOfForm();
  } else {
    form.collapseIndex(index, indexes, multiplicities, elements);
  }
  _decrementHelper(indexes, multiplicities, elements);
  if (indexes.isEmpty) return FormIndex.beginningOfForm();
  return form.buildIndex(indexes, multiplicities, elements)!;
}