addChild method

bool addChild(
  1. int index
)

Implementation

bool addChild(int index) {
  assert(_debugAssertChildListLocked());
  _createOrObtainChild(index);
  final child = this[index];
  if (child != null) {
    assert(indexOf(child) == index);
    return true;
  }
  childManager.setDidUnderflow(true);
  return false;
}