Observer2<A, B> constructor
const
Observer2<A, B> ({})
Constructs an Observer2 widget.
The listenable
parameter is the first reactive variable to listen to.
The listenable2
parameter is the second reactive variable to listen to.
The listener
parameter is a callback function that defines the widget to rebuild whenever either of the reactive variables changes.
Implementation
const Observer2({
Key? key,
required this.listenable,
required this.listenable2,
required this.listener,
}) : super(key: key);