我的搜索栏没有从列表视图中过滤任何数据。谁能告诉我我的 onItemChanged() 函数出了什么问题以及如何解决这个问题？

Question

该应用仅显示列表视图，但不过滤任何数据。如果我在搜索栏中输入任何内容，列表视图将保持不变


class Home extends StatefulWidget {
  const Home({Key? key}) : super(key: key);

  @override
  _HomeState createState() => new _HomeState();
}

class _HomeState extends State<Home> {
  Future<List> getData() async {
    final response =
        await http.get(Uri.parse("http://192.168.0.166/api/conn2.php"));

    return json.decode(response.body);
  }

  @override
  Widget build(BuildContext context) {
    return new Scaffold(
        appBar: new AppBar(
          title: new Text("MY APP"),
        ),
        body: Center(child: ListSearch()));
  }
}

class ListSearch extends StatefulWidget {
  ListSearchState createState() => ListSearchState();
}

class ListSearchState extends State<ListSearch> {
  TextEditingController _textController = TextEditingController();
  List newList = [];

  onItemChanged(String value) {
    setState(() {
      newList = MyStatelessWidget(
        list: [],
      )
          .list
          .where((string) => string.toLowerCase().contains(value.toLowerCase()))
          .toList(); //copying api data into newList
    });
  }

  @override
  Widget build(BuildContext context) {
    return Scaffold(
      body: Column(
        children: <Widget>[
          Padding(
            padding: const EdgeInsets.all(12.0),
            child: TextField(
              controller: _textController,
              decoration: InputDecoration(
                hintText: "Search here....",
                border: OutlineInputBorder(
                    borderRadius: BorderRadius.circular(4.0)),
                focusedBorder: OutlineInputBorder(
                    borderSide: BorderSide(color: Colors.black)),
                prefixIcon: Icon(Icons.search),
                suffixIcon: IconButton(
                  onPressed: _textController.clear,
                  icon: Icon(Icons.clear),
                ),
              ),
              onChanged: onItemChanged, //onItemChanged() called here
            ),
          ),
          Expanded(
            child: new FutureBuilder<List>(
              future: _HomeState().getData(),
              builder: (context, snapshot) {
                if (snapshot.hasError) print(snapshot.error);

                return snapshot.hasData
                    ? new MyStatelessWidget(
                        list: snapshot.data ?? [],
                      )
                    : new Center(
                        child: CircularProgressIndicator(),
                      );
              },
            ),
          )
        ],
      ),
    );
  }
}

数据库包含'Articles','Features','Features2','Description' table

    class _ArticleDescription extends StatelessWidget {
      const _ArticleDescription({
        Key? key,
        required this.articles,
        required this.features,
        required this.features2,
        //required this.description,
    
      }) : super(key: key);
    
      final String articles;
      final String features;
      final String features2;
      // final String description;
    
    
      @override
      Widget build(BuildContext context) {
        return Column(
          crossAxisAlignment: CrossAxisAlignment.start,
          children: <Widget>[
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                children: <Widget>[
                  Text(
                    articles,
                    maxLines: 1,
                    overflow: TextOverflow.ellipsis,
                    style: const TextStyle(
                      fontWeight: FontWeight.bold,
                    ),
                  ),
                  const Padding(padding: EdgeInsets.only(bottom: 2.0)),
                  Text(
                    features,
                    maxLines: 2,
                    overflow: TextOverflow.ellipsis,
                    style: const TextStyle(
                      fontSize: 12.0,
                      color: Colors.black54,
                    ),
                  ),
                ],
              ),
            ),
            Expanded(
              child: Column(
                crossAxisAlignment: CrossAxisAlignment.start,
                mainAxisAlignment: MainAxisAlignment.end,
                children: <Widget>[
                  Text(
                    features2,
                    style: const TextStyle(
                      fontSize: 12.0,
                      color: Colors.black87,
                    ),
                  ),
                  /*Text(
                    description,
                    style: const TextStyle(
                      fontSize: 12.0,
                      color: Colors.black54,
                    ),
                  ),*/
                ],
              ),
            ),
          ],
        );
      }
    }

自定义列表视图

    class CustomListItemTwo extends StatelessWidget {
      const CustomListItemTwo({
        Key? key,
        required this.thumbnail,
        required this.articles,
        required this.features,
        required this.features2,
        // required this.description,
    
      }) : super(key: key);
      final Widget thumbnail;
      final String articles;
      final String features;
      final String features2;
      //final String description;
    
    
      @override
      Widget build(BuildContext context) {
        return Padding(
          padding: const EdgeInsets.symmetric(vertical: 10.0),
          child: SizedBox(
            height: 80,
            child: Row(
              crossAxisAlignment: CrossAxisAlignment.start,
              children: <Widget>[
                AspectRatio(
                  aspectRatio: 0.8,
                  child: thumbnail,
                ),
                Expanded(
                  child: Padding(
                    padding: const EdgeInsets.fromLTRB(20.0, 0.0, 2.0,0.0),
                    child: _ArticleDescription(
                      articles: articles,
                      features: features,
                      features2: features2,
                      // description: description,
    
                    ),
                  ),
                )
              ],
            ),
          ),
        );
      }
    }
    class MyStatelessWidget extends StatelessWidget {
      final List list;
    //final  List<String> list;
    
    
      const MyStatelessWidget({ required this.list});
    
      //const MyStatelessWidget({Key? key, required this.list}) : super(key: key);
    
      @override
      Widget build(BuildContext context) {
        return ListView.builder(
            itemCount: list == null ? 0 : list.length,
            itemBuilder: (context, i) {
              return Container(
                padding: const EdgeInsets.all(10.0),
                child: new GestureDetector(
                  onTap: ()=>Navigator.of(context).push(
                      new MaterialPageRoute(
                          builder: (BuildContext context)=> new Detail(list:list , index: i,)
                      )
                  ),
    
                  child:Column(
    
                    children:<Widget> [
                      CustomListItemTwo(
                        thumbnail: Container(
                          decoration: const BoxDecoration(color: Colors.blue),
                        ),
    
                        articles: (list[i]['Articles']),
                        features: (list[i]['Features']),
                        features2: (list[i]['Features2']),
                        //description: (list[i]['Description']),
    
                      ),
    
                    ],
                  ),
                ),
              );
            }
        );
      }
    }

Answer 1

  @override
  Widget build(BuildContext context) {
    return ListView.builder(
        itemCount: list == null ? 0 : list.length,
        ....

至

  @override
  Widget build(BuildContext context) {
  var activeList = searchlist ;
  //create isSearchBar bool var. and change 
  //true if search is Active
  //false if search is inActive
  isSearchBar
    ? activeList = searchlist 
    : activeList  = list;
    return ListView.builder(
        itemCount: activeList == null ? 0 : activeList.length,
        ....
             articles: (activeList[i]['Articles']),
        ....

我的搜索栏没有从列表视图中过滤任何数据。谁能告诉我我的 onItemChanged() 函数出了什么问题以及如何解决这个问题？

My search bar is not filtering any data from listview. Can anyone tell me what's wrong with my onItemChanged() function and how to solve the issue?

searchbar

flutter