Flutter报错NoSuchMethodError：null调用data getter问题求助

尝试关联文章页面与搜索页面内容时，出现以下错误：

构建Builder(dirty)时抛出NoSuchMethodError：
在null对象上调用了getter 'data'。
接收者：null
尝试调用：data

相关代码如下：

class _SearchPageState extends State<SearchPage> {
  List<Article> _searchedPost = [];

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      appBar: AppBar(
        title: TextField(
          style: const TextStyle(color: Colors.white),
          decoration: const InputDecoration(
              hintText: 'Search Post',
              hintStyle: TextStyle(color: Colors.white),
              border: InputBorder.none),
          onChanged: (val) {
            setState(() {
              _searchedPost =
                  widget.posts.where((el) => el.title.contains(val)).toList();
            });
          },
        ),
      ),

      /// Body
      body: _searchedPost.isEmpty
          ? Center(
              child: Text(
                'Nessun articolo disponibile',
                textAlign: TextAlign.center,
                style: Theme.of(context).textTheme.headline6,
              ),
            )
          : ListView.builder(
              itemCount: _searchedPost.length,
              itemBuilder: (context, i) {
                return Column(
                  mainAxisSize: MainAxisSize.min,
                  children: <Widget>[
                    Card(
                      margin: const EdgeInsets.all(10),
                      elevation: 5,
                      shadowColor: Colors.black26,
                      color: Colors.white,
                      child: InkWell(
                        child: ClipRRect(
                          borderRadius: BorderRadius.circular(10),
                          child: Column(
                            mainAxisSize: MainAxisSize.min,
                            children: [
                              _searchedPost[i].urlImage == null
                                  ? const Text("Nessuna immagine caricata")
                                  : Image.network(
                                      _searchedPost[i].urlImage,
                                      width: double.infinity,
                                      height: 220,
                                      fit: BoxFit.cover,
                                    ),
                              // Title article
                              Column(
                                children: [
                                  Padding(
                                    padding: const EdgeInsets.only(
                                        left: 16, top: 16, bottom: 16),
                                    child: Row(
                                      children: [
                                        Expanded(
                                          child: Text(
                                            _searchedPost[i].title,
                                            maxLines: 3,
                                            overflow: TextOverflow.clip,
                                            softWrap: true,
                                            style: const TextStyle(
                                              fontSize: 18,
                                              fontWeight: FontWeight.w600,
                                              fontFamily: "Raleway",
                                            ),
                                          ),
                                        ),
                                      ],
                                    ),
                                  )
                                ],
                              ),
                            ],
                          ),
                        ),
                        onTap: () {
                          Navigator.push(
                            context,
                            MaterialPageRoute(
                              builder: (context) => ArticlePage(
                                data: snapshot.data?[i],
                              ),
                            ),
                          );
                        },
                      ),
                    ),
                  ],
                );
              },
            ),
    );
  }
}

错误根源是代码里的snapshot变量根本没在当前作用域定义，属于无中生有。现在搜索后的文章数据都存在_searchedPost列表里，跳转ArticlePage时应该传这个列表对应索引的元素。

修改onTap回调里的代码：

onTap: () {
  Navigator.push(
    context,
    MaterialPageRoute(
      builder: (context) => ArticlePage(
        data: _searchedPost[i],
      ),
    ),
  );
},

如果想更严谨，避免极端情况下列表元素为空的问题，可以加个空值判断：

onTap: () {
  final targetArticle = _searchedPost[i];
  if (targetArticle != null) {
    Navigator.push(
      context,
      MaterialPageRoute(
        builder: (context) => ArticlePage(data: targetArticle),
      ),
    );
  }
},

内容的提问来源于stack exchange，提问作者Pimpi Rimpà