build method

@override Widget build()

Subclasses should override this function to actually call the appropriate build function (e.g., StatelessWidget.build or State.build) for their widget.

Implementation

@override
Widget build() {
  // TODO disallow didChangeDependencies
  try {
    _oldDependencies = _dependencies;
    for (var i = 0; i < _listeners.length; i++) {
      _listeners[i].close();
    }
    _listeners.clear();
    _dependencies = {};
    return super.build();
  } finally {
    for (final dep in _oldDependencies!.values) {
      dep.close();
    }
    _oldDependencies = null;
  }
}