What is addListener in Dart?

addListener method Null safety Adds a listener callback that is called whenever a new concrete ImageInfo object is available or an error is reported . If a concrete image is already available, or if an error has been already reported, this object will notify the listener synchronously.

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What is notify listener in flutter?

notifyListeners method Null safety Call this method whenever the object changes, to notify any clients the object may have changed . Listeners that are added during this iteration will not be visited. Listeners that are removed during this iteration will not be visited after they are removed.

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