【发布时间】：2021-07-31 12:21:22
【问题描述】：
我有一个使用 listview 显示客户列表的屏幕。接下来，当我单击客户时，我想在列表视图的下一个屏幕中仅显示该特定客户（customerId）的注释（记录）。我知道如何显示表格的所有记录。但如何只显示某些记录？既没有任何错误，也没有显示列表视图。我不知道我哪里错了。
List<CustomerNote> cnoteList;
int count = 0;
if (cnoteList == null) {
cnoteList = List<CustomerNote>();
updateCustomerNotes();
}
db_service.dart
Future<List<CustomerNote>> getCustomerNotes(int customer) async {
await DB.init();
var res = await DB.rawQuery("noteDetails WHERE custId = '$customer'");
int count = res.length;
List<CustomerNote> cnotelist = List<CustomerNote>();
for (int i = 0; i < count; i++) {
cnotelist.add(CustomerNote.fromMap(res[i]));
}
return cnotelist;
}
People_List.dart //这是显示客户列表的文件
import 'package:customer/models/Note.dart';
import 'package:customer/models/addCustomer.dart';
import 'package:customer/screens/New_Note.dart';
import 'package:customer/screens/Note_info.dart';
import 'package:customer/screens/User_Settings.dart';
import 'package:customer/screens/add_person.dart';
import 'package:customer/services/db_service.dart';
import 'package:customer/utils/database_helper.dart';
import 'package:flutter/material.dart';
import 'dart:io';
import 'package:sqflite/sqflite.dart';
class People_List extends StatefulWidget{
@override
State<StatefulWidget> createState() {
return People_ListState();
}
}
class People_ListState extends State<People_List> with SingleTickerProviderStateMixin{
DBService dbService = DBService();
List<AddCustomer> customerList;
int count = 0;
static final GlobalKey<ScaffoldState> scaffoldKey = new GlobalKey<ScaffoldState>();
var _isSelectedItemIndex;
TextEditingController _searchQuery;
bool _isSearching = false;
String searchQuery = "Search query";
@override
void initState() {
super.initState();
_searchQuery = new TextEditingController();
}
void _startSearch() {
print("open search box");
ModalRoute
.of(context)
.addLocalHistoryEntry(new LocalHistoryEntry(onRemove: _stopSearching));
setState(() {
_isSearching = true;
});
}
void _stopSearching() {
_clearSearchQuery();
setState(() {
_isSearching = false;
});
}
void _clearSearchQuery() {
print("close search box");
setState(() {
_searchQuery.clear();
updateSearchQuery("Search query");
});
}
Widget _buildTitle(BuildContext context) {
var horizontalTitleAlignment =
Platform.isIOS ? CrossAxisAlignment.center : CrossAxisAlignment.start;
return new InkWell(
onTap: () => scaffoldKey.currentState.openDrawer(),
child: new Padding(
padding: const EdgeInsets.symmetric(horizontal: 12.0),
child: new Column(
mainAxisAlignment: MainAxisAlignment.center,
crossAxisAlignment: horizontalTitleAlignment,
children: <Widget>[
const Text(''),
],
),
),
);
}
Widget _buildSearchField() {
return new TextField(
controller: _searchQuery,
autofocus: true,
decoration: const InputDecoration(
hintText: 'Search...',
border: InputBorder.none,
hintStyle: const TextStyle(color: Colors.white30),
),
style: const TextStyle(color: Colors.white, fontSize: 16.0),
onChanged: updateSearchQuery,
);
}
void updateSearchQuery(String newQuery) {
setState(() {
searchQuery = newQuery;
});
print("search query " + newQuery);
}
List<Widget> _buildActions() {
if (_isSearching) {
return <Widget>[
new IconButton(
icon: const Icon(Icons.clear),
onPressed: () {
if (_searchQuery == null || _searchQuery.text.isEmpty) {
Navigator.pop(context);
return;
}
_clearSearchQuery();
},
),
];
}
return <Widget>[
new IconButton(
icon: const Icon(Icons.search),
onPressed: _startSearch,
),
];
}
@override
Widget build(BuildContext context) {
var height = MediaQuery.of(context).size.height;
var width = MediaQuery.of(context).size.width;
if (customerList == null) {
customerList = List<AddCustomer>();
updateListView();
}
return Scaffold(
appBar: new AppBar(
leading: _isSearching ? const BackButton() : null,
title: _isSearching ? _buildSearchField() : _buildTitle(context),
actions: _buildActions(),
),
body:getCustomerListView(),
floatingActionButton: FloatingActionButton(
onPressed: () {
navigateToCustomer(AddCustomer(), 'Add Person');
},
child: const Icon(Icons.add),
),
bottomNavigationBar:Row (
children: <Widget>[
buildNavBarItem(Icons.home,0,"Home"),
buildNavBarItem(Icons.fiber_new_rounded,1,"Upcoming"),
buildNavBarItem(Icons.history,2,"History"),
buildNavBarItem(Icons.account_circle,3,"Account"),
],
),
);
}
ListView getCustomerListView() {
TextStyle titleStyle = Theme.of(context).textTheme.subhead;
return ListView.builder(
itemCount: count,
itemBuilder: (BuildContext context, int position) {
return Card(
color: Colors.white,
elevation: 2.0,
child: ListTile(
/*trailing: CircleAvatar(
backgroundColor: getPriorityColor(this.noteList[position].priority),
child: getPriorityIcon(this.noteList[position].priority),
),*/
title: Text(this.customerList[position].custName, style: titleStyle,),
//subtitle: Text(this.customerList[position].date),
onTap: () {
},
),
);
},
);
}
void navigateToCustomer(AddCustomer customer, String title) async {
bool result = await Navigator.push(context, MaterialPageRoute(builder: (context) {
return AddPerson(customer, title);
}));
if (result == true) {
updateListView();
}
}
void updateListView() {
final Future<Database> dbFuture = DB.init();
dbFuture.then((database) {
Future<List<AddCustomer>> customerListFuture = dbService.getCustomerList();
customerListFuture.then((customerList) {
setState(() {
this.customerList = customerList;
this.count = customerList.length;
});
});
});
}
Widget buildNavBarItem(IconData icon,int index,title) {
var height = MediaQuery.of(context).size.height;
var width = MediaQuery.of(context).size.width;
return GestureDetector(
onTap: () {
setState(() {
_isSelectedItemIndex=index;
if(_isSelectedItemIndex==3) {
Navigator.of(context).push(MaterialPageRoute(
builder: (BuildContext context) => User_Settings()));
}
});
},
child: Container(
height: height * 0.09,
width: width / 4,
decoration: index==_isSelectedItemIndex?BoxDecoration(
border: Border(
bottom: BorderSide(width: 4,color: Theme.of(context).primaryColor),
),
gradient: LinearGradient(colors: [
Theme.of(context).primaryColor.withOpacity(0.3),
Theme.of(context).primaryColor.withOpacity(0.015),
],begin: Alignment.bottomCenter,end: Alignment.topCenter)
):BoxDecoration(),
child: Column(
children: <Widget>[
InkWell(
child: Icon(icon,
color: index==_isSelectedItemIndex? Theme.of(context).primaryColor:Colors.black54,
),
),
Text(title)
],)),
);
}
}
Note_Info.dart
class Note_Info extends StatefulWidget{
final String appBarTitle;
final AddCustomer customer;
Note_Info(this. customer, this.appBarTitle);
@override
State<StatefulWidget> createState() {
return Note_InfoState(this.customer,this.appBarTitle);
}
}
class Note_InfoState extends State<Note_Info> {
CustomerNote note=CustomerNote();
DBService dbService = DBService();
List<CustomerNote> cnoteList;
int count = 0;
String appBarTitle;
AddCustomer customer;
Note_InfoState(this.customer, this.appBarTitle);
PickedFile _imageFile;
final ImagePicker _picker = ImagePicker();
bool rememberMe = false;
DateTime _date = DateTime.now();
TextEditingController custNameController = TextEditingController();
void getImage(ImageSource source) async {
final pickedFile = await _picker.getImage(
source: source);
setState(() {
_imageFile = pickedFile;
});
}
@override
Widget build(BuildContext context) {
if (noteList == null) {
noteList = List<CustomerNote>();
updateCustomerNotes();
}
var height = MediaQuery.of(context).size.height;
custNameController.text = customer.custName;
return DefaultTabController(
length: 4,
child: Scaffold(
appBar: AppBar(
actions: [
IconButton(
icon: Icon(
Icons.add,
),
onPressed: () {
Navigator.of(context).push(MaterialPageRoute(
builder: (BuildContext context) => NewNote()));
},
)
],
),
body: Container(
child: Column(
children: <Widget>[
TextField(controller: custNameController,
style: TextStyle(
fontSize: 20.0, fontWeight: FontWeight.bold),
textAlign: TextAlign.center),
Padding(
padding: const EdgeInsets.all(15.0),
child: Row(children: [
ImageProfile(),
Padding(
padding: const EdgeInsets.only(left: 30.0),
child: IconButton(
icon: Icon(
Icons.call,
color: Colors.green,
size: 45,
),
onPressed: () {
},
),
),
],),
),
SizedBox(
height: 50,
child: AppBar(
bottom: TabBar(
tabs: [
Tab(
text: "All",
),
Tab(
text: "Pending",
),
Tab(
text: "Cancelled",
),
Tab(
text: "Completed",
),
],
),
),
),
// create widgets for each tab bar here
Expanded(
child: TabBarView(
children: [
// first tab bar view widget
Container(
child: getNoteListView(),
),
// second tab bar view widget
Container(
child: Center(
child: Text(
'Pending Items',
),
),
),
Container(
child: Center(
child: Text(
'Cancelled',
),
),
),
Container(
child: Center(
child: Text(
'Completed',
),
),
),
],
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
height: 55.0,
width: 200,
child: RaisedButton(
elevation: 2,
shape: RoundedRectangleBorder(
borderRadius: BorderRadius.circular(20)),
color: Theme
.of(context)
.primaryColorDark,
textColor: Colors.white,
child: Text('Save', textScaleFactor: 1.5,),
onPressed: () {
setState(() {
//_reset();
});
},
),
),
),
]
),
)
));
}
void updateCustomerNotes() {
final Future<Database> dbFuture = DB.init();
dbFuture.then((database) {
int customerId=customer.custId;
Future<List<CustomerNote>> noteListFuture = dbService.getCustomerNotes(customerId);
noteListFuture.then((cnoteList) {
setState(() {
this.cnoteList = cnoteList;
//this.count = cnoteList.length;
});
});
});
}
ListView getNoteListView() {
TextStyle titleStyle = Theme.of(context).textTheme.subhead;
return ListView.builder(
itemCount: count,
itemBuilder: (BuildContext context, int position) {
return Card(
color: Colors.white,
elevation: 2.0,
child: ListTile(
title: Text(this.cnoteList[position].note, style: titleStyle,),
subtitle: Text(this.cnoteList[position].date),
trailing: GestureDetector(
child: Icon(Icons.delete, color: Colors.grey,),
onTap: () {
},
),
onTap: () {
},
),
);
},
);
}
void _showSnackBar(BuildContext context, String message) {
final snackBar = SnackBar(content: Text(message));
Scaffold.of(context).showSnackBar(snackBar);
}
Widget ImageProfile() {
return Center(
child: CircleAvatar(
radius: 80.0,
backgroundImage: AssetImage('images/person_icon.jpg')
),
);
}
}
【问题讨论】：