【发布时间】：2021-03-16 16:32:07
【问题描述】：
我在我的项目中使用table_calendar 包，但到目前为止我遇到了两个问题：
- 日历不会在日历下方加载今天的事件，我很想听听一些关于如何完成这一任务的想法。
- 即使我将（下面的代码）放入表格参数中，它也不允许切换日历模式。
为我的问题的第二个要点切换日历模式的代码：
availableCalendarFormats: const {
CalendarFormat.month: '',
CalendarFormat.week: '',
},
以防万一，这里是有问题的页面的整个代码：
class Lecture_graph extends StatefulWidget {
Lecture_graph({Key key}) : super(key: key);
@override
State<Lecture_graph> createState() => myLectureGraph();
}
class myLectureGraph extends State<Lecture_graph>
with TickerProviderStateMixin {
List _selectedEvents;
DateTime _selectedDate = DateTime.now();
Map<DateTime, List<Lecture>> _events;
CalendarController _calendarController;
AnimationController _animationController;
List<Lecture> _lectures;
String coursecode = "";
bool isJoin, isBreaks = false;
bool isLoading = true;
final Map<DateTime, List> _holidays = {
// DateTime(2021, 1, 1): ['New Year\'s Day'],
// DateTime(2021, 2, 14): ['Valentine\'s Day'],
// DateTime(2021, 3, 8): ['Woman\'s Day'],
};
Future<Map<DateTime, List>> getLectures(DateTime _selectedDate) async {
print("getLectures started.");
setState(() {
isLoading = true;
});
Map<DateTime, List<Lecture>> mapFetch = {};
//get saved course
if (coursecode == "" || coursecode == null) {
coursecode = await _checkSavedCourse();
//debug
print('courscode recieved from sharedprefs');
}
//build request URL
var requestURL =
'https://lekcijas.va.lv/lekcijas_android/getMonthLectures.php?date=' +
DateFormat('yyyy-MM').format(_selectedDate) +
(isBreaks ? "&breaks" : "") +
(isJoin ? "&join" : "") +
"&program=" +
coursecode +
"&lang=" +
AppLocalizations.of(context).translate('request_language');
print("Lecture request url : $requestURL");
//wait for response
var response = await http.get(Uri.parse(requestURL));
var data = json.decode(response.body)["result"];
//clear array after each request
if (_lectures != null) _lectures.clear();
try {
//create lectures from json response
_lectures = List<Lecture>.from(data.map((x) => Lecture.fromJson(x)));
} on Exception catch (_) {
print("Error occured getting lectures");
}
_lectures.forEach((element) {
if (mapFetch[element.lecture_date] != null) {
mapFetch[element.lecture_date] += [element];
} else {
mapFetch[element.lecture_date] = [element];
}
});
setState(() {
isLoading = false;
});
print("getLectures finished.");
return mapFetch;
}
Future<void> _saveVales(String key, bool value) async {
SharedPreferences prefs = await SharedPreferences.getInstance();
print("Sharedpref $key is set to $value now");
prefs.setBool(key, value);
}
Future<void> _checkSavedParameters() async {
SharedPreferences prefs = await SharedPreferences.getInstance();
isBreaks = prefs.getBool('lectures_breaks') == null
? false
: prefs.getBool('lectures_breaks');
isJoin = prefs.getBool('lectures_join') == null
? false
: prefs.getBool('lectures_join');
}
Future<String> _checkSavedCourse() async {
//check saved parameters for lecture requests too
await _checkSavedParameters();
SharedPreferences prefs = await SharedPreferences.getInstance();
String _coursecode = prefs.getString('savedCourse');
if (_coursecode == "" || _coursecode == null) {
Navigator.pop(context);
Navigator.push(
context,
MaterialPageRoute(builder: (context) => CourseSelectionPage()),
);
return null;
} else {
return _coursecode;
}
}
void _onDaySelected(DateTime day, List events) {
print('CALLBACK: _onDaySelected');
setState(() {
_selectedEvents = events;
});
}
@override
void initState() {
super.initState();
//enable portrait only mode
SystemChrome.setPreferredOrientations([
DeviceOrientation.portraitUp,
DeviceOrientation.portraitDown,
]);
_selectedEvents = [];
_calendarController = CalendarController();
_animationController = AnimationController(
vsync: this,
duration: const Duration(milliseconds: 400),
);
_animationController.forward();
WidgetsBinding.instance.addPostFrameCallback((_) {
getLectures(_selectedDate).then((val) => setState(() {
_events = val;
}));
});
}
@override
void dispose() {
_calendarController.dispose();
//unlock orientation mode
SystemChrome.setPreferredOrientations([
DeviceOrientation.landscapeRight,
DeviceOrientation.landscapeLeft,
DeviceOrientation.portraitUp,
DeviceOrientation.portraitDown,
]);
super.dispose();
}
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(coursecode +
" | " +
AppLocalizations.of(context).translate('lectures_title')),
actions: <Widget>[
IconButton(
icon: Icon(
Icons.settings,
color: Colors.white,
),
onPressed: () {
showDialog(
context: context,
builder: (context) {
return StatefulBuilder(
builder: (context, setState) {
return AlertDialog(
title: Text(
AppLocalizations.of(context).translate('settings')),
content: Column(
mainAxisSize: MainAxisSize.min,
children: [
Row(
children: [
CupertinoSwitch(
value: isJoin,
onChanged: (bool value) {
_saveVales('lectures_join', value);
isJoin = value;
WidgetsBinding.instance
.addPostFrameCallback((_) {
getLectures(_selectedDate)
.then((val) => setState(() {
_events = val;
}));
});
},
),
Text(AppLocalizations.of(context)
.translate('join_lectures'))
],
),
SizedBox(height: 10),
Row(
children: [
CupertinoSwitch(
value: isBreaks,
onChanged: (bool value) {
_saveVales('lectures_breaks', value);
isBreaks = value;
WidgetsBinding.instance
.addPostFrameCallback((_) {
getLectures(_selectedDate)
.then((val) => setState(() {
_events = val;
}));
});
},
),
Text(AppLocalizations.of(context)
.translate('show_breaks'))
],
),
SizedBox(height: 10),
SizedBox(
width: double.infinity,
child: OutlinedButton(
onPressed: () {
//close popup
Navigator.pop(context);
//close page
Navigator.pop(context);
Navigator.push(
context,
MaterialPageRoute(
builder: (context) =>
CourseSelectionPage()),
);
},
child: Text(
AppLocalizations.of(context)
.translate('select_course'),
style: TextStyle(color: Colors.lime),
)),
)
],
),
actions: <Widget>[
FlatButton(
onPressed: () => Navigator.pop(context),
child: Text(AppLocalizations.of(context)
.translate('close')),
),
],
);
},
);
},
);
},
)
],
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
isLoading
? Expanded(child: Center(child: CircularProgressIndicator()))
: _buildTableCalendarWithBuilders(),
const SizedBox(height: 2.0),
Expanded(child: _buildEventList()),
],
),
),
);
}
Widget _buildTableCalendarWithBuilders() {
return Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Card(
color: Colors.white,
margin: const EdgeInsets.all(8.0),
clipBehavior: Clip.antiAlias,
child: TableCalendar(
locale:
AppLocalizations.of(context).translate('request_language') ==
'lv'
? "lv_LV"
: "en_US",
initialSelectedDay: _selectedDate,
calendarController: _calendarController,
events: _events,
holidays: _holidays,
initialCalendarFormat: CalendarFormat.month,
formatAnimation: FormatAnimation.scale,
startingDayOfWeek: StartingDayOfWeek.monday,
availableGestures: AvailableGestures.all,
availableCalendarFormats: const {
CalendarFormat.month: '',
CalendarFormat.week: '',
},
calendarStyle: CalendarStyle(
outsideDaysVisible: false,
weekendStyle: TextStyle().copyWith(color: Colors.blue[800]),
holidayStyle: TextStyle().copyWith(color: Colors.blue[800]),
),
daysOfWeekStyle: DaysOfWeekStyle(
weekendStyle: TextStyle().copyWith(color: Colors.blue[600]),
),
headerStyle: HeaderStyle(
centerHeaderTitle: true,
formatButtonVisible: false,
),
builders: CalendarBuilders(
selectedDayBuilder: (context, date, _) {
return FadeTransition(
opacity:
Tween(begin: 0.0, end: 1.0).animate(_animationController),
child: Container(
margin: const EdgeInsets.all(4.0),
padding: const EdgeInsets.only(top: 5.0, left: 6.0),
color: Colors.deepOrange[300],
width: 100,
height: 100,
child: Text(
'${date.day}',
style: TextStyle().copyWith(fontSize: 16.0),
),
),
);
},
todayDayBuilder: (context, date, _) {
return Container(
margin: const EdgeInsets.all(4.0),
padding: const EdgeInsets.only(top: 5.0, left: 6.0),
color: Colors.amber[400],
width: 100,
height: 100,
child: Text(
'${date.day}',
style: TextStyle().copyWith(fontSize: 16.0),
),
);
},
markersBuilder: (context, date, events, holidays) {
final children = <Widget>[];
if (events.isNotEmpty) {
children.add(
Positioned(
right: 1,
bottom: 1,
child: _buildEventsMarker(date, events),
),
);
}
if (holidays.isNotEmpty) {
children.add(
Positioned(
right: -2,
top: -2,
child: _buildHolidaysMarker(),
),
);
}
return children;
},
),
onDaySelected: (date, events, holidays) {
_onDaySelected(date, events);
_animationController.forward(from: 0.0);
},
onVisibleDaysChanged: _onVisibleDaysChanged,
),
),
],
);
}
void _onVisibleDaysChanged(
DateTime first, DateTime last, CalendarFormat format) {
_selectedDate = first;
WidgetsBinding.instance.addPostFrameCallback((_) {
getLectures(_selectedDate).then((val) => setState(() {
_events = val;
}));
});
print('CALLBACK: _onVisibleDaysChanged');
}
Widget _buildEventsMarker(DateTime date, List events) {
return AnimatedContainer(
duration: const Duration(milliseconds: 300),
decoration: BoxDecoration(
shape: BoxShape.circle,
color: _calendarController.isSelected(date)
? Colors.brown[500]
: _calendarController.isToday(date)
? Colors.brown[300]
: Colors.green[400],
),
width: 18.0,
height: 18.0,
child: Center(
child: Text(
'${events.length}',
style: TextStyle().copyWith(
color: Colors.white, fontSize: 12.0, fontWeight: FontWeight.w900),
),
),
);
}
Widget _buildHolidaysMarker() {
return Icon(
Icons.add_box,
size: 20.0,
color: Colors.blueGrey[800],
);
}
Widget _buildEventList() {
return ListView(
children: _selectedEvents.reversed
.map((lecture) => Container(
decoration: BoxDecoration(
border: Border.all(width: 0.1),
// borderRadius: BorderRadius.circular(2.0),
color: hexToColor(lecture.color),
),
margin:
const EdgeInsets.symmetric(horizontal: 6.0, vertical: 1.5),
child: ListTile(
title: Column(
children: [
Align(
alignment: Alignment.centerLeft,
child: Text(
lecture.start + " - " + lecture.end,
style: new TextStyle(
fontSize: 12.0,
color: Colors.black,
),
),
),
Align(
alignment: Alignment.centerLeft,
child: Text(lecture.lecture,
style: new TextStyle(
fontSize: 16.0,
color: Colors.black,
)),
),
],
),
onTap: () => displayDialog(lecture, context),
),
))
.toList(),
);
}
void displayDialog(Lecture selectedLecture, BuildContext ctx) {
//if selected lecture is a break
if (!selectedLecture.lecturer.isEmpty &&
!selectedLecture.classroom.isEmpty &&
!selectedLecture.programs.isEmpty) {
showDialog(
barrierDismissible: true,
context: ctx,
builder: (BuildContext context) => new AlertDialog(
title: new Text(AppLocalizations.of(context).translate('info_title')),
content: new Wrap(
runSpacing: 5,
children: [
Align(
alignment: Alignment.centerLeft,
child: Text(
AppLocalizations.of(context).translate('info_time') +
selectedLecture.start +
" - " +
selectedLecture.end),
),
Align(
alignment: Alignment.centerLeft,
child: Text(
AppLocalizations.of(context).translate('info_lecturer') +
selectedLecture.lecturer),
),
Align(
alignment: Alignment.centerLeft,
child: Text(
AppLocalizations.of(context).translate('info_classroom') +
selectedLecture.classroom),
),
Align(
alignment: Alignment.centerLeft,
child: Text(
AppLocalizations.of(context).translate('info_lecture') +
selectedLecture.lecture),
),
Align(
alignment: Alignment.centerLeft,
child: Text(
AppLocalizations.of(context).translate('info_date') +
DateFormat('yyyy-MM-dd')
.format(selectedLecture.lecture_date)
.toString()),
),
Align(
alignment: Alignment.centerLeft,
child: Text(
AppLocalizations.of(context).translate('info_programs') +
selectedLecture.programs),
),
],
),
actions: [
new TextButton(
child: Text(AppLocalizations.of(context).translate('close')),
onPressed: () => Navigator.pop(context, true),
),
],
),
);
}
}
}
如果有人想查看 JSON 请求结果，here 就是那个链接。
【问题讨论】：
标签： flutter