英文:
search bar I can't find anything
问题
我是新手编程者，我一直在尝试编写搜索栏的代码，但我发现我的搜索栏存在问题，它似乎无法搜索我想要的内容，好像什么都找不到。我尝试修复了一段时间，但仍然遇到了相同的问题。我从不同的网站学习了一些东西，然后进行了修复，但仍然卡在了同一个问题上，我认为也许我将代码写在了错误的地方，但我的代码没有任何错误。
类 view_problem 扩展 StatefulWidget {
@override
State<view_problem> createState() => _view_problemState();
}
类 _view_problemState 扩展 State<view_problem> {
TextEditingController _searchController = TextEditingController();
List<problemModel> problemlist = [];
StreamController _streamController = StreamController();
Future getAllProblem() async {
problemlist = await problemcontrollers().getProblem();
_streamController.sink.add(problemlist);
}
@override
void initState() {
// TODO: implement initState
Timer.periodic(Duration(seconds: 1), (timer) {
getAllProblem();
});
super.initState();
}
void _filterSearch(String query) {
List<problemModel> filteredList = [];
for (var item in problemlist) {
if (item.toString().contains(query.toString())) {
filteredList.add(item);
}
}
setState(() {
problemlist = filteredList;
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
backgroundColor: Color.fromARGB(255, 14, 12, 134),
title: const Text('show information'),
),
body: Container(
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: TextField(
onChanged: (value) {
_filterSearch(value);
},
controller: _searchController,
decoration: InputDecoration(
labelText: "search",
prefixIcon: Icon(Icons.search),
border: OutlineInputBorder(
borderRadius: BorderRadius.all(Radius.circular(25.0)))),
),
),
Expanded(
child: StreamBuilder(
stream: _streamController.stream,
builder: (context, snapshots) {
if (snapshots.hasData) {
return ListView.builder(
itemCount: problemlist.length,
itemBuilder: ((context, index) {
problemModel problem = problemlist[index];
return Card(
margin: EdgeInsets.all(10),
child: ListTile(
title: Text(
problem.name_surname,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 19),
),
subtitle: Text(
problem.area,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 17),
),
trailing: Text(
problem.status,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 16),
),
),
);
}));
}
return Center(
child: CircularProgressIndicator(),
);
},
),
)
],
),
),
);
}
}
英文:
I'm new to coding and I've been trying to code the search bar for a while now but I've found that my search bar has a problem where it doesn't search what I want, it seems like it can't find anything. I tried to fix it for a while but still got the same problem. I studied from different websites. and then fix it, still stuck on the same problem, I think maybe I wrote the code in a wrong place but my code doesn't have any error.enter image description here
class view_problem extends StatefulWidget {
@override
State<view_problem> createState() => _view_problemState();
}
class _view_problemState extends State<view_problem> {
TextEditingController _searchController = TextEditingController();
List<problemModel> problemlist = [];
StreamController _streamController = StreamController();
Future getAllProblem() async {
problemlist = await problemcontrollers().getProblem();
_streamController.sink.add(problemlist);
}
@override
void initState() {
// TODO: implement initState
Timer.periodic(Duration(seconds: 1), (timer) {
getAllProblem();
});
super.initState();
}
void _filterSearch(String query) {
List<problemModel> filteredList = [];
for (var item in problemlist) {
if (item.toString().contains(query.toString())) {
filteredList.add(item);
}
}
setState(() {
problemlist = filteredList;
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
backgroundColor: Color.fromARGB(255, 14, 12, 134),
title: const Text('show information'),
),
body: Container(
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: TextField(
onChanged: (value) {
_filterSearch(value);
},
controller: _searchController,
decoration: InputDecoration(
labelText: "search",
prefixIcon: Icon(Icons.search),
border: OutlineInputBorder(
borderRadius: BorderRadius.all(Radius.circular(25.0)))),
),
),
Expanded(
child: StreamBuilder(
stream: _streamController.stream,
builder: (context, snapshots) {
if (snapshots.hasData) {
return ListView.builder(
itemCount: problemlist.length,
itemBuilder: ((context, index) {
problemModel problem = problemlist[index];
return Card(
margin: EdgeInsets.all(10),
child: ListTile(
title: Text(
problem.name_surname,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 19),
),
subtitle: Text(
problem.area,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 17),
),
trailing: Text(
problem.status,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 16),
),
),
);
}));
}
return Center(
child: CircularProgressIndicator(),
);
},
),
)
],
),
),
);
}
}
答案1
得分: 0
你有一个定时器每秒定期运行，永远获取所有问题，这会覆盖任何过滤器。我认为你不想要那个定时器，只需在initState中调用一次getAllProblem()。然后将originalList保存在另一个变量中。类似这样
class _view_problemState extends State<view_problem> {
TextEditingController _searchController = TextEditingController();
List<problemModel> problemlist = [];
List<problemModel> originalList = [];
StreamController _streamController = StreamController();
Future getAllProblem() async {
problemlist = await problemcontrollers().getProblem();
originalList = problemlist;
_streamController.sink.add(problemlist);
}
@override
void initState() {
getAllProblem();
super.initState();
}
void _filterSearch(String query) {
List<problemModel> filteredList = [];
for (var item in originalList) {
if (item.toString().contains(query.toString())) {
filteredList.add(item);
}
}
setState(() {
problemlist = filteredList;
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
backgroundColor: Color.fromARGB(255, 14, 12, 134),
title: const Text('show information'),
),
body: Container(
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: TextField(
onChanged: (value) {
_filterSearch(value);
},
controller: _searchController,
decoration: InputDecoration(
labelText: "search",
prefixIcon: Icon(Icons.search),
border: OutlineInputBorder(
borderRadius: BorderRadius.all(Radius.circular(25.0)))),
),
),
Expanded(
child: StreamBuilder(
stream: _streamController.stream,
builder: (context, snapshots) {
if (snapshots.hasData) {
return ListView.builder(
itemCount: problemlist.length,
itemBuilder: ((context, index) {
problemModel problem = problemlist[index];
return Card(
margin: EdgeInsets.all(10),
child: ListTile(
title: Text(
problem.name_surname,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 19),
),
subtitle: Text(
problem.area,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 17),
),
trailing: Text(
problem.status,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 16),
),
),
);
}));
}
return Center(
child: CircularProgressIndicator(),
);
},
),
)
],
),
),
);
}
}
英文:
You have a timer running periodically running every second forever that gets all problems, which will overwrite any filtering. I don't think you want that timer there, and just do getAllProblem(); once in the initState. And save the originalList in another variable. Something like this
class _view_problemState extends State<view_problem> {
TextEditingController _searchController = TextEditingController();
List<problemModel> problemlist = [];
List<problemModel> originalList = [];
StreamController _streamController = StreamController();
Future getAllProblem() async {
problemlist = await problemcontrollers().getProblem();
originalList = problemlist;
_streamController.sink.add(problemlist);
}
@override
void initState() {
getAllProblem();
super.initState();
}
void _filterSearch(String query) {
List<problemModel> filteredList = [];
for (var item in originalList) {
if (item.toString().contains(query.toString())) {
filteredList.add(item);
}
}
setState(() {
problemlist = filteredList;
});
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
backgroundColor: Color.fromARGB(255, 14, 12, 134),
title: const Text('show information'),
),
body: Container(
child: Column(
children: <Widget>[
Padding(
padding: const EdgeInsets.all(8.0),
child: TextField(
onChanged: (value) {
_filterSearch(value);
},
controller: _searchController,
decoration: InputDecoration(
labelText: "search",
prefixIcon: Icon(Icons.search),
border: OutlineInputBorder(
borderRadius: BorderRadius.all(Radius.circular(25.0)))),
),
),
Expanded(
child: StreamBuilder(
stream: _streamController.stream,
builder: (context, snapshots) {
if (snapshots.hasData) {
return ListView.builder(
itemCount: problemlist.length,
itemBuilder: ((context, index) {
problemModel problem = problemlist[index];
return Card(
margin: EdgeInsets.all(10),
child: ListTile(
title: Text(
problem.name_surname,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 19),
),
subtitle: Text(
problem.area,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 17),
),
trailing: Text(
problem.status,
style: TextStyle(
fontWeight: FontWeight.bold, fontSize: 16),
),
),
);
}));
}
return Center(
child: CircularProgressIndicator(),
);
},
),
)
],
),
),
);
}
}
</details>
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