Navigator.push().then not calling a Function - flutter

Question

This is my students list screen, which has an add student button and upon taping save on the form it pops back to the students list.
class _StudentListState extends State<StudentList> {
var students = new List<Student>();
_getStudents() {
APIServices.fetchStudents().then((response) {
setState(() {
Iterable list = json.decode(response);
students = list.map((model) => Student.fromJson(model)).toList();
});
});
}
#override
void initState() {
super.initState();
_getStudents();
}
#override
Widget build(BuildContext context) {
return Scaffold(
floatingActionButton:_buidFloatingButton(),
appBar: _buildAppBar(context),
bottomNavigationBar: BottomAppBar(
// ================== REFRESH BUTTON ============================
child: FlatButton(
child:Icon(Icons.refresh),
onPressed: () {
_getStudents();
},
),
// =======================================================
),
// ================== ADD STUDENT BUTTON =======================
Widget _buidFloatingButton() {
return FloatingActionButton(
child:Icon(Icons.person_add),
onPressed: () {
Navigator.push(context, MaterialPageRoute(builder: (context) => AddStudent())).then((value) {
_getStudents();
});
},
);
}
// =======================================================
}
}
I'm trying to refresh the student list after the form pop with this code, as seen in above code:
Navigator.push(context, MaterialPageRoute(builder: (context) => AddStudent())).then((value) => () {
_getStudents();
});
It's not refreshing the student list, but it will refresh if I tap the refresh button, both attempts are executing the same _getStudentes() function.
At the end of the save button I just do a:
Navigator.pop(context);
What am I missing?
Thanks.

Answer 1

You are returning a function with (value) => () { ... }.
The shorthand syntax in JavaScript and Dart differs a little in that regard, let me explain:
// Expression that returns a function.
() {
...
}
// You could also assign it to a variable:
final foo = () { return 3; };
// Now, you can call foo:
final bar = foo();
Thus, you are returning a function with (value) => () { ... }.
What you want to do instead is either of the following:
(value) => _getStudents()
// or
(value) {
_getStudents();
}
Learn more about functions in Dart.