In my case i had code like this (in class state)
final GlobalKey<ScaffoldState> _scaffoldKey = new GlobalKey<ScaffoldState>();
void showInSnackBar(String value) {
_scaffoldKey.currentState.showSnackBar(new SnackBar(content: new Text(value)));
}
but i didn’t setup the key for scaffold.
so when i add key: _scaffoldKey
@override
Widget build(BuildContext context) {
return new Scaffold(
key: _scaffoldKey,
body: new SafeArea(
snackbar start to work 🙂