在此小部件上方找不到正确的提供者 [英] Could not find the correct provider above this widget

问题描述

我在使用Flutter Provider时遇到问题...
我的流程是这样的：登录用户ID传递到新的小部件之后->从那里将其预先保存到db，然后将其重定向到新的小部件（仪表板）。

I have a problem using Flutter Provider... My flow is like this: After login user id is passed to new widget -> from there it preforms save to db and then it redirects to new widget (Dashboard).

这是登录后的小部件代码：

And this is a code of a widget after Login:

return MaterialApp(
      title: title,
      home: Scaffold(
          appBar: AppBar(
            title: Text(title),
          ),
          body: ListView(
            children: <Widget>[
              Container(
                margin: EdgeInsets.all(8.0),
                child: Card(
                  shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.all(Radius.circular(8.0))),
                  child: InkWell(
                    onTap: () {
                      var user = Provider.of<UserRepository>(context);
                      user.savePreference(user.user.id, "Something");
                      user.navigateToNewPage(Dashboard(), context);
                      print(user.user.id);
                    },

这有效：

user.savePreference(user.user.id, "Something");

但这会引起问题：

user.navigateToNewPage(Dashboard(), context);

在仪表板小部件中，我正在创建以下内容：

In Dashboard widget I am creating this:

 Widget build(BuildContext context) {
    var user = Provider.of<UserRepository>(context);

在UserRepository中，我有以下内容：

And in UserRepository I have this:

class UserRepository with ChangeNotifier {
  User user;
  Status _status = Status.Uninitialized;

  Status get status => _status;
  User get getUser => user;

  UserRepository.instance();

Future<void> navigateToNewPage(Widget page, BuildContext context) {
    Navigator.push(context, MaterialPageRoute(builder: (context) => page));
  }

我知道本主题已经解决了问题，但找不到适合的主题是我的问题。

I know this topic has already solved questions, but could not find anything suitable to my problem.

推荐答案

尝试将脚手架下面的部分小部件树提取到单独的小部件中。
您现在使用的上下文用于构建尚未导航的顶层窗口小部件。

Try extracting part of your widget tree that lies below Scaffold to a separate widget. The context you are using now is used to build your top level widget which does not Navigator yet.

生成的代码应如下所示：

The resulting code should look like that:

return MaterialApp(
      title: title,
      home: Scaffold(
          appBar: AppBar(
            title: Text(title),
          ),
          body: LoginWidget()

class LoginWidget extends StatelessWidget {
  @override
  Widget build(BuildContext context) {
    return ListView(
            children: <Widget>[
              Container(
                margin: EdgeInsets.all(8.0),
                child: Card(
                  shape: RoundedRectangleBorder(
                      borderRadius: BorderRadius.all(Radius.circular(8.0))),
                  child: InkWell(
                    onTap: () {
                      var user = Provider.of<UserRepository>(context);
                      user.savePreference(user.user.id, "Something");
                      user.navigateToNewPage(Dashboard(), context);
                      print(user.user.id);
                    },

...

  }
}

这篇关于在此小部件上方找不到正确的提供者的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！