“Null”类型不是 flutter 中“String”类型的子类型

Question

Widget build(BuildContext context) {
final routeArgs =
    ModalRoute.of(context).settings.arguments as Map<String, String>;
final categoryTitle = routeArgs['title'];
final categoryId = routeArgs['id'];
return Scaffold(
  appBar: AppBar(
    title: Text(categoryTitle),
  ),

请帮帮我这是我面临的错误

Answer 1

我认为你的 routeArgs['title'] 是 null 并且当你把它放在文本中时它会产生错误尝试

Text(categoryTitle??"")