Should codes be written before super.initState(); or after in Flutter?

both will work.

But if you see from any dependencies or official docs flutter, write your code in initSate() after super.initState();

@overrride
initState(){
  super.initState()
  //your code
}

reference to this initState

the opposite for dispose(), write your code before super.dispose();

@overrride
dispose(){
  //your code
  super.dispose()
}

reference to dispose

When I see @Kahoo answer, I check it by cmd + click at super.dispose and super.initstate, I found this for dispose

  /// If you override this, make sure to end your method with a call to
  /// super.dispose().
  ///
  /// See also:
  ///
  ///  * [deactivate], which is called prior to [dispose].
  @protected
  @mustCallSuper
  void dispose() {
    assert(_debugLifecycleState == _StateLifecycle.ready);
    assert(() {
      _debugLifecycleState = _StateLifecycle.defunct;
      return true;
    }());
  }

abstract class State :

  /// If you override this, make sure your method starts with a call to
  /// super.initState().
  @protected
  @mustCallSuper
  void initState() {
    assert(_debugLifecycleState == _StateLifecycle.created);
  }