flutter - 如果祖先关闭，Snackbar 操作会给出“查找已停用小部件的祖先是不安全的”错误

Question

我有带有文件夹名称列表的 showModalBottomSheet。如果用户想将文件添加到文件夹中，请单击添加，ModalBottomSheet 将显示，用户点击文件夹名称并调用 bloc 事件将文件添加到文件夹中。如果成功，我将获得 CreateFavouriteSuccess 状态，如果成功，则关闭 Modal 并显示小吃店如下。到目前为止还可以。问题是，如果用户单击快餐栏操作，我会收到以下错误。Snackbar 将在 3 秒内自动隐藏，并且 Ok 操作会立即关闭。

我了解 Navigator.of(context).pop(); 关闭祖先，shwoModalBottomSheet。我可以知道如何解决这个问题。

错误

FlutterError (Looking up a deactivated widget's ancestor is unsafe.
At this point the state of the widget's element tree is no longer stable.
To safely refer to a widget's ancestor in its dispose() method, save a reference to the ancestor by calling dependOnInheritedWidgetOfExactType() in the widget's didChangeDependencies() method.)

代码

Widget build(BuildContext context) {
return BlocListener<FavouriteBloc, FavouriteState>(
  listener: (context, state) {
    if (state is FavouriteError) {
      isSubmitButtonActive = false;
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          backgroundColor: Colors.red,
          content: AutoSizeText(state.error),
          duration: const Duration(seconds: 3),
          action: SnackBarAction(
            label: kYes,
            onPressed: () {
              ScaffoldMessenger.of(context).hideCurrentSnackBar();
            },
          ),
        ),
      );
    } else if (state is Processing) {
      setState(() {
        isSubmitButtonActive = false;
      });
    } else if (state is CreateFavouriteSuccess) {
      ScaffoldMessenger.of(context).showSnackBar(
        SnackBar(
          content: AutoSizeText(state.successMessage),
          duration: const Duration(seconds: 3),
          action: SnackBarAction(
            label: kYes,
            onPressed: () {
              ScaffoldMessenger.of(context).hideCurrentSnackBar();
            },
          ),
        ),
      );
      Navigator.of(context).pop();
    } else if (state is CreateDownloadSuccess) {
      Navigator.of(context).pop();
    }
  },
  child: _favouriteForm(widget.socialMode),
);
}

Widget _favouriteForm(SocialMode socialMode) {
return FormBuilder(
  key: formKey,
  autovalidateMode: AutovalidateMode.disabled,
  child: Center(
    child: SingleChildScrollView(
      child: Column(
        mainAxisAlignment: MainAxisAlignment.center,
        children: [
          const SizedBox(
            height: 20,
          ),
          SizedBox(
            width: MediaQuery.of(context).size.width * 0.9,
            child: FormBuilderTextField(
              textInputAction: TextInputAction.next,
              name: "name",
              validator: FormBuilderValidators.compose([
                FormBuilderValidators.required(context),
              ]),
              decoration: InputDecoration(
                contentPadding: const EdgeInsets.all(8),
                prefixIcon: const Icon(Icons.favorite_outline),
                hintText: "Enter playlist name",
                hintStyle: kHintStyle,
                fillColor: Colors.grey[200],
                filled: true,
                enabledBorder: kOutlineBorder,
                focusedBorder: kOutlineBorder,
                errorBorder: kOutlineErrorBorder,
                focusedErrorBorder: kOutlineErrorBorder,
              ),
            ),
          ),
          const SizedBox(
            height: 20,
          ),
          CustomButton(
            onPressed: () async {
              if (formKey.currentState!.validate()) {
                create(socialMode, widget.currentMediaItem);
              }
            },
            child: const Text("Create"),
          )
        ],
      ),
    ),
  ),
);
}

Answer 1

实际上，我应该在主页收听成功状态并显示 Snackbar，因为我使用的是 bloc 状态。