Dart Analyze

Dart Analyze

Community Analyzer

Don't put any logic in createState DRT-W1023

Bug risk
Major

DON'T put any logic in createState().

Implementations of createState() should return a new instance of a State object and do nothing more. Since state access is preferred via the widget field, passing data to State objects using custom constructor parameters should also be avoided and so further, the State constructor is required to be passed no arguments.

BAD:

MyState global;

class MyStateful extends StatefulWidget {
  @override
  MyState createState() {
    global = MyState();
    return global;
  }
}
class MyStateful extends StatefulWidget {
  @override
  MyState createState() => MyState()..field = 42;
}
class MyStateful extends StatefulWidget {
  @override
  MyState createState() => MyState(42);
}

GOOD:

class MyStateful extends StatefulWidget {
  @override
  MyState createState() {
    return MyState();
  }
}