解决 setState() called after dispose()

if (mounted) {
  setState(() {
    selectedDate = new DateTime(selectedDate.year, selectedDate.month, selectedDate.day, picked.hour, picked.minute);
  });
}

@override
  void initState() {
    foo_bar(); // call setState();
    super.initState(); // then foo_bar()
  }

Right code:

@override
  void initState() {
    super.initState();
    foo_bar(); // first call super constructor then foo_bar that contains setState() call
  }