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.
What does addListener do flutter?
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.