subscribeSticky method

Subscription<T> subscribeSticky(
  1. Observer<T> observer
)

添加观察者，并且会立马回调当前值

Implementation

Subscription<T> subscribeSticky(Observer<T> observer) {
  final sub = subscribe(observer);
  Future.delayed(Duration.zero, () {
    observer.call(_value);
  });
  return sub;
}