我是Flutter编程的初学者。 我调用了一个Web API来获取ListView项目。我需要对此ListView进行过滤。 当我在搜索框中输入任何文本时，将显示“正在等待结果”世界，然后再次呈现列表，而没有任何过滤结果。我在搜索框中输入的字母都会调用Web API 我厌倦了许多解决方案，但没有一个对我有用。 代码是：
import 'package:flutter/cupertino.dart';
import 'package:flutter/material.dart';
import 'package:flutter/widgets.dart';
import 'package:soft_ta/Models/EmployeeExceptionModel.dart';
import 'package:soft_ta/Widget/sharedWidget.dart' as shared;
import 'package:easy_localization/easy_localization.dart';
import 'package:flutter_slidable/flutter_slidable.dart';
import 'package:soft_ta/HelperClass.dart';
import 'package:soft_ta/Remote/WepAPI.dart';
class EmployeesExceptios extends StatefulWidget {
@override
State<StatefulWidget> createState() {
return new _EmployeesExceptiosState();
}
}
class _EmployeesExceptiosState extends State<EmployeesExceptios> {
TextEditingController _textController = TextEditingController();
List<EmployeeExceptionModel> employeeExceptionModelList =
new List<EmployeeExceptionModel>();
final _scaffoldKey = GlobalKey<ScaffoldState>();
HelperClass helper = new HelperClass();
List<EmployeeExceptionModel> newDataList = new List<EmployeeExceptionModel>();
onItemChanged(String value) {
setState(() {
newDataList = employeeExceptionModelList
.where((a) =>
a.EmployeeId.toString() == (value.toString().toLowerCase()))
.toList();
});
}
@override
Widget build(BuildContext context) {
final height = MediaQuery.of(context).size.height;
return FutureBuilder(
future: Future.wait([_getEmployeeException()]),
builder: (BuildContext context, AsyncSnapshot<List<dynamic>> snapshot) {
switch (snapshot.connectionState) {
case ConnectionState.none:
return new Text('Press button to start');
case ConnectionState.waiting:
return new Text('Awaiting result...');
default:
if (snapshot.hasError)
return new Text('Error: ${snapshot.error}');
else {
employeeExceptionModelList = snapshot.data[0];
newDataList = employeeExceptionModelList;
return Scaffold(
key: _scaffoldKey,
body: Container(
decoration: BoxDecoration(
gradient: LinearGradient(
begin: Alignment.topRight,
end: Alignment.bottomLeft,
colors: [Colors.white, Colors.blueGrey])),
height: height,
child: Stack(
children: [
Container(
padding: EdgeInsets.only(top: 20),
child: Column(
children: [
shared.divider(
value:
"EmployeeExceptions".tr().toString()),
],
),
),
Padding(
padding: EdgeInsets.only(top: height * .10),
child: TextField(
controller: _textController,
decoration: InputDecoration(
hintText: 'Search Here by EmployeeId...',
),
onChanged: onItemChanged,
),
),
Padding(
padding: EdgeInsets.only(top: height * .20),
child: Container(
// height: height,
padding: EdgeInsets.symmetric(horizontal: 20),
child: Container(
child: ListView.separated(
separatorBuilder: (context, index) =>
Divider(
color: Colors.black,
),
itemCount: newDataList.length,
itemBuilder: (context, int index) {
return Slidable(
actions: <Widget>[
IconSlideAction(
icon: Icons.more,
caption: 'MORE',
color: Colors.blue,
onTap: () {
print(
"More ${newDataList[index]} is Clicked");
}),
],
secondaryActions: <Widget>[
IconSlideAction(
icon: Icons.clear,
color: Colors.red,
caption: 'Cancel',
onTap: () {
print(
"Cancel ${newDataList[index]} is Clicked");
})
],
child: ListTile(
// leading: Icon(Icons.message),
title: Text(
"${newDataList[index].EmployeeId}",
style: TextStyle(
fontSize: 16.0,
fontWeight: FontWeight.bold,
fontFamily: 'Arial'),
),
subtitle: Column(
crossAxisAlignment:
CrossAxisAlignment.start,
children: [
Text(
"${newDataList[index].FromDT}",
style: TextStyle(
color: Colors.blueGrey,
fontSize: 13.0),
),
Text(
"${newDataList[index].ExceptionName}",
style: TextStyle(
color: Colors.blueGrey,
fontSize: 13.0),
),
],
),
trailing: Icon(Icons.arrow_back),
),
actionPane: SlidableDrawerActionPane(),
);
}),
),
),
),
],
),
));
}
}
});
}
Future<List<EmployeeExceptionModel>> _getEmployeeException() async {
var _wepAPI = new WebAPI();
List<EmployeeExceptionModel> lst = new List<EmployeeExceptionModel>();
EmployeeExceptionModel objEmployeeExceptionModel;
List value =
await _wepAPI.getEmployeesExceptions(helper.getCurrentUserId());
value.forEach((element) {
objEmployeeExceptionModel = new EmployeeExceptionModel();
objEmployeeExceptionModel.AssignmentId = element["AssignmentId"];
objEmployeeExceptionModel.EmployeeId = element["EmployeeId"];
objEmployeeExceptionModel.EmployeeName = element["EmployeeName"];
objEmployeeExceptionModel.AprvStsId = element["AprvStsId"];
objEmployeeExceptionModel.ExceptionName = element["ExceptionName"];
objEmployeeExceptionModel.ExceptionTypeName =
element["ExceptionTypeName"];
objEmployeeExceptionModel.FromDT = element["FromDT"];
objEmployeeExceptionModel.ToDT = element["ToDT"];
lst.add(objEmployeeExceptionModel);
});
return lst;
}
}