Hi这是我的新代码，当我执行此代码时，我在_selectedEvents的值Notifier处收到错误。im试图使用API来获取数据，当包更新时，以下json格式的数据im没有适当的文档来从API获取事件并显示在table_calender 中
API：
{
"payment_status": "1",
"mass_dates": {
"start_date": "2022-09-05",
"end_date": "2022-09-17"
},
"church_details": {
"church_name": "Church"
},
"quote": {
"quote_id": "3",
"quote": "And do not forget to do good and to share with others, for with such sacrifices God is pleased.",
"verse": "Hebrews 13:16"
},
"mass_list": [
{
"mass_id": "958",
"mass_date": "2022-09-05",
"mass_time": "06:30 am",
"mass_amount": "120",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "959",
"mass_date": "2022-09-05",
"mass_time": "06:00 pm",
"mass_amount": "100",
"mass_notes": "Kannada Mass",
"mass_place": "Second Mass",
"mass_detail": "New mass"
},
{
"mass_id": "960",
"mass_date": "2022-09-06",
"mass_time": "06:00 pm",
"mass_amount": "130",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "961",
"mass_date": "2022-09-07",
"mass_time": "06:00 pm",
"mass_amount": "140",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "962",
"mass_date": "2022-09-08",
"mass_time": "06:30 am",
"mass_amount": "150",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "963",
"mass_date": "2022-09-09",
"mass_time": "06:00 pm",
"mass_amount": "160",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "964",
"mass_date": "2022-09-10",
"mass_time": "06:30 am",
"mass_amount": "170",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "965",
"mass_date": "2022-09-10",
"mass_time": "06:00 pm",
"mass_amount": "180",
"mass_notes": "Kannada Mass",
"mass_place": "Second Mass",
"mass_detail": "This is Mass is with Sunday Liturgy"
},
{
"mass_id": "966",
"mass_date": "2022-09-11",
"mass_time": "07:00 am",
"mass_amount": "100",
"mass_notes": "English Mass",
"mass_place": "First Mass",
"mass_detail": "This mass is once a week"
},
{
"mass_id": "967",
"mass_date": "2022-09-11",
"mass_time": "08:15 am",
"mass_amount": "110",
"mass_notes": "Kannada Mass",
"mass_place": "Second Mass",
"mass_detail": "This is the Parish main mass"
},
{
"mass_id": "968",
"mass_date": "2022-09-12",
"mass_time": "06:30 am",
"mass_amount": "120",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "969",
"mass_date": "2022-09-12",
"mass_time": "06:00 pm",
"mass_amount": "100",
"mass_notes": "Kannada Mass",
"mass_place": "Second Mass",
"mass_detail": "New mass"
},
{
"mass_id": "970",
"mass_date": "2022-09-13",
"mass_time": "06:00 pm",
"mass_amount": "130",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "971",
"mass_date": "2022-09-14",
"mass_time": "06:00 pm",
"mass_amount": "140",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "972",
"mass_date": "2022-09-15",
"mass_time": "06:30 am",
"mass_amount": "150",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "973",
"mass_date": "2022-09-16",
"mass_time": "06:00 pm",
"mass_amount": "160",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "974",
"mass_date": "2022-09-17",
"mass_time": "06:30 am",
"mass_amount": "170",
"mass_notes": "Kannada Mass",
"mass_place": "First Mass",
"mass_detail": "No Details"
},
{
"mass_id": "975",
"mass_date": "2022-09-17",
"mass_time": "06:00 pm",
"mass_amount": "180",
"mass_notes": "Kannada Mass",
"mass_place": "Second Mass",
"mass_detail": "This is Mass is with Sunday Liturgy"
}
]
}
dart文件如下：
import 'dart:collection';
import 'dart:convert';
import 'package:flutter/material.dart';
import 'package:flutter_spinkit/flutter_spinkit.dart';
import 'package:google_fonts/google_fonts.dart';
import 'package:mysorediocese/Constants/color_constant.dart';
import 'package:mysorediocese/Constants/urls.dart';
import 'package:mysorediocese/models/index.dart';
import 'package:mysorediocese/pages/cores/UtilsTableCalender.dart';
import 'package:mysorediocese/pages/widgets/bottom_navigation_travelkuy.dart';
import 'package:nb_utils/nb_utils.dart';
import 'package:table_calendar/table_calendar.dart';
import 'package:http/http.dart' as http;
class MassIntensionMassListScreen extends StatefulWidget {
@override
_MassIntensionMassListScreenState createState() => _MassIntensionMassListScreenState();
}
int getHashCode(DateTime key) {
return key.day * 1000000 + key.month * 10000 + key.year;
}
class _MassIntensionMassListScreenState extends State<MassIntensionMassListScreen> with TickerProviderStateMixin{
Masslist_page masslist_page=new Masslist_page();
late String parish_key, uid, msg;
String fam_head = "Loved";
String churchname = "Our Church";
late SharedPreferences prefs;
late bool error, showprogress;
late final ValueNotifier<List<MassListDetatils>> _selectedEvents;
CalendarFormat _calendarFormat = CalendarFormat.week;
RangeSelectionMode _rangeSelectionMode = RangeSelectionMode
.toggledOff; // Can be toggled on/off by longpressing a date
late DateTime _focusedDay;
DateTime? _selectedDay;
DateTime? _rangeStart;
DateTime? _rangeEnd;
var kEvents;
Future<void> _fetchdata() async {
prefs = await SharedPreferences.getInstance();
setState(() {
parish_key = prefs.getString("parish_key") ?? "Loved";
uid = prefs.getString("uid") ?? "Loved";
fam_head = prefs.getString("fam_head") ?? "Loved";
});
String apiurl =
mMassListPage; //api url
//dont use http://localhost , because emulator don't get that address
//insted use your local IP address or use live URL
//hit "ipconfig" in windows or "ip a" in linux to get you local IP
try{
var response = await http.post(Uri.parse(apiurl), body: {
//get the username text
'uid':uid,
'parish_key': parish_key //get password text
}).whenComplete(() => action());
if (response.statusCode == 200)
{
var jsondata1 = json.decode(response.body);
masslist_page = Masslist_page.fromJson(jsondata1);
_focusedDay = DateTime.parse(masslist_page.mass_dates.start_date);
_selectedDay = _focusedDay;
_selectedEvents = ValueNotifier(_getEventsForDay(_selectedDay!));
var kEventSource= Map<DateTime, List<MassListDetatils>>.fromIterable(masslist_page.mass_list,key: (element) => DateTime.parse(masslist_page.mass_list[element].mass_time),value: (element) => masslist_page.mass_list);
kEvents = LinkedHashMap<DateTime, List<MassListDetatils>>(
equals: isSameDay,
hashCode: getHashCode,
)..addAll(kEventSource);
} else {
msg = "No data Error connecting";
}
}catch(e){
print(e);
// Navigator.of(context)
// .pushNamedAndRemoveUntil(mSplashScreenRoute, (Route<dynamic> route) => false);
}
}
@override
void initState() {
showprogress = true;
_fetchdata();
super.initState();
}
@override
void dispose() {
_selectedEvents.dispose();
super.dispose();
}
List<MassListDetatils> _getEventsForDay(DateTime day) {
// Implementation example
return kEvents[day] ?? [];
}
List<DateTime> daysInRange(DateTime first, DateTime last) {
final dayCount = last.difference(first).inDays + 1;
return List.generate(
dayCount,
(index) => DateTime.utc(first.year, first.month, first.day + index),
);
}
List<MassListDetatils> _getEventsForRange(DateTime start, DateTime end) {
// Implementation example
final days = daysInRange(start, end);
return [
for (final d in days) ..._getEventsForDay(d),
];
}
void _onDaySelected(DateTime selectedDay, DateTime focusedDay) {
if (!isSameDay(_selectedDay, selectedDay)) {
setState(() {
_selectedDay = selectedDay;
_focusedDay = focusedDay;
_rangeStart = null; // Important to clean those
_rangeEnd = null;
_rangeSelectionMode = RangeSelectionMode.toggledOff;
});
_selectedEvents.value = _getEventsForDay(selectedDay);
}
}
void _onRangeSelected(DateTime? start, DateTime? end, DateTime focusedDay) {
setState(() {
_selectedDay = null;
_focusedDay = focusedDay;
_rangeStart = start;
_rangeEnd = end;
_rangeSelectionMode = RangeSelectionMode.toggledOn;
});
// `start` or `end` could be null
if (start != null && end != null) {
_selectedEvents.value = _getEventsForRange(start, end);
} else if (start != null) {
_selectedEvents.value = _getEventsForDay(start);
} else if (end != null) {
_selectedEvents.value = _getEventsForDay(end);
}
}
@override
Widget build(BuildContext context) {
return showprogress
? Scaffold(
body: Container(
child: Center(child: SpinKitCubeGrid(color: Colors.blue))),
)
: Scaffold(
appBar: AppBar(
backgroundColor: mBackgroundColor,
title: Wrap(
children: [
Text(
masslist_page.church_details.church_name,
style: GoogleFonts.dancingScript(
textStyle: TextStyle(
color: Colors.blue[800],
letterSpacing: .5,
fontSize: 26,
fontWeight: FontWeight.w900)),
),
],
),
elevation: 1,
),
// Setting up Background Color
backgroundColor: mBackgroundColor,
// Setting up Custom Bottom Navigation Bar
bottomNavigationBar: BottomNavigationTravelkuy(0),
body: Column(
children: [
TableCalendar<MassListDetatils>(
firstDay: DateTime.parse(masslist_page.mass_dates.start_date),
lastDay: DateTime.parse(masslist_page.mass_dates.end_date),
focusedDay: _focusedDay,
selectedDayPredicate: (day) => isSameDay(_selectedDay, day),
rangeStartDay: _rangeStart,
rangeEndDay: _rangeEnd,
calendarFormat: _calendarFormat,
rangeSelectionMode: _rangeSelectionMode,
eventLoader: _getEventsForDay,
startingDayOfWeek: StartingDayOfWeek.monday,
calendarStyle: CalendarStyle(
// Use `CalendarStyle` to customize the UI
outsideDaysVisible: false,
),
onDaySelected: _onDaySelected,
onRangeSelected: _onRangeSelected,
onFormatChanged: (format) {
if (_calendarFormat != format) {
setState(() {
_calendarFormat = format;
});
}
},
onPageChanged: (focusedDay) {
_focusedDay = focusedDay;
},
),
const SizedBox(height: 8.0),
Expanded(
child: ValueListenableBuilder<List<MassListDetatils>>(
valueListenable: _selectedEvents,
builder: (context, value, _) {
return ListView.builder(
itemCount: value.length,
itemBuilder: (context, index) {
return Container(
margin: const EdgeInsets.symmetric(
horizontal: 12.0,
vertical: 4.0,
),
decoration: BoxDecoration(
border: Border.all(),
borderRadius: BorderRadius.circular(12.0),
),
child: ListTile(
onTap: () => print('${value[index].mass_time}'),
title: Text('${value[index].mass_id} ${value[index].mass_date} '),
),
);
},
);
},
),
),
],
),
);
}
action() {
setState(() {
showprogress = false;
});
}
}
looking forward for your kind support
使用
var mass= masslist_page.mass_list.groupListsBy((element) => DateTime.parse(element.mass_date));
并将分组传递给
kEvents = LinkedHashMap<DateTime, List<MassListDetatils>>(
equals: isSameDay,
hashCode: getHashCode,
)..addAll(mass);
这解决了从Api获取数据并将其传递给flutter中的表日历插件的问题。它对API中的日期进行分组，并将其传递给列表映射，并使用该列表映射以获取特定日期的事件的tablecalendar插件指定的喜欢的列表格式传递它。masslist_page.mass_list是为生成的json API 创建的模型