anchor.diff:  
     @override
     Widget build(BuildContext context) {
  +    final double statusBarHeight = MediaQuery.of(context).padding.top;
       return new Scaffold(
         key: _homeKey,
         scrollableKey: _scrollableKey,
  
positive.code:         )
        ),
        appBarBehavior: AppBarBehavior.under,
        body: new Block(
         scrollableKey: _scrollableKey,
         children: _listItems
        )
      );
  
negative.code:   void initState() {
      super.initState();
  
      final ThemeData themeData = Theme.of(context);
      final TextStyle headerStyle = themeData.textTheme.body2.copyWith(color: themeData.accentColor);
      String category;
  