Question

我尝试使用HTTP URL从Flutter Firebase获取数据，但是发生了此错误。请帮我解决这个错误。 [错误：flutter / lib / ui / ui_dart_state.cc（166）]未处理的异常：类型'String'不是'index'的'int'类型的子类型 Products.fetchAndSetProducts 谢谢

Future<void> fetchAndSetProducts([bool filterByUser = false]) async {
  final filterString = filterByUser ? 'orderBy="creatorId"&equalTo="$userId"' :'';
  var url = 'https://cowmilknew.firebaseio.com/products.json?auth=$authToken&$filterString';
  try {
    final response = await http.get(url);
    final extractedData = json.decode(response.body) as Map<String, dynamic>;
    if (extractedData == null) {
      return;
    }
     url =
    'https://cowmilknew.firebaseio.com/RetailerWishlist/$userId.json?auth=$authToken';
    final favoriteResponse = await http.get(url);
    final favoriteData = json.decode(favoriteResponse.body);

    final List<Product> loadedProducts = [];
    extractedData.forEach((prodId, prodData) {
      loadedProducts.add(Product(
        id: prodId,
        title: prodData['title'],
        description: prodData['description'],
        price: prodData['price'],
        isFavorite: favoriteData == null ? false : favoriteData[prodId] ?? false,
        imageUrl: prodData['imageUrl'],
      ));
    });
    _items = loadedProducts;
    notifyListeners();
  } catch (error) {
    throw (error);
  }
}

@override
  void didChangeDependencies() {
    if (_isInit) {
      setState(() {
        _isLoading = true;
      });
      Provider.of<Products>(context,listen: false).fetchAndSetProducts().then((_) {
        setState(() {
          _isLoading = false;
        });
      });
    }
    _isInit = false;
    super.didChangeDependencies();
  }

Answer 1

由于您没有提供完整的错误日志，所以我无法确切告诉您错误的位置，但是很显然您正在尝试将int传递给字符串，因此我猜测错误的原因可能在于价格： prodData ['price'] 这样做会将价格转换为整数吗？

price: prodData['price'].toString();

错误：Flutter / lib / ui / ui_dart_state.cc（166）未处理的异常：类型'String'不是'index'的'int'类型的子类型

1 个答案: