setAll method Null safety

  1. @override
void setAll(
  1. int index,
  2. Iterable<E> iterable
)

Overwrites elements with the objects of iterable.

The elements of iterable are written into this list, starting at position index.

var list = ['a', 'b', 'c', 'd'];
list.setAll(1, ['bee', 'sea']);
list.join(', '); // 'a, bee, sea, d'

This operation does not increase the length of the list.

The index must be non-negative and no greater than length.

The iterable must not have more elements than what can fit from index to length.

If iterable is based on this list, its values may change during the setAll operation.

Implementation

@override
void setAll(int index, Iterable<E> iterable) {
  RangeError.checkValidRange(index, index + iterable.length, length, "index",
      "index + iterable.length");

  // Listen to the element that will be added
  for (E element in iterable) {
    if (_propagateNotification &&
        element != null &&
        element is ChangeNotifier) {
      element.addListener(_propagate);
    }
  }

  // Stop listening to the element that will be replaced
  for (int i = index; i < index + iterable.length; i++) {
    E element = elementAt(i);
    if (_propagateNotification &&
        element != null &&
        element is ChangeNotifier) {
      element.addListener(_propagate);
    }
  }

  _values.setAll(index, iterable);
  notifyListeners();
}