我正在自己学习颤振。 尝试使用轮播日历制作 doto Calendar。
问题是
@第 238 行
如果我输入如下代码，则每当我按下日期按钮时，日历都会不断刷新。
return snapshot.hasData && _markedDateMap.events.length > 0 ...
如果我把代码写成下面这样，我可爱的大日期按钮就会变小！！
return snapshot.hasData ...
这个问题有什么解决办法吗？ 请帮助我阻止未来的建设者继续建设！ TT
import 'package:flutter/material.dart';
import 'package:flutter_calendar_carousel/flutter_calendar_carousel.dart'
show CalendarCarousel;
import 'package:flutter_calendar_carousel/classes/event.dart';
import 'package:flutter_calendar_carousel/classes/event_list.dart';
import 'package:intl/intl.dart' show DateFormat;
import 'package:http/http.dart' as http;
import 'dart:convert';
import 'package:flutter/foundation.dart';
import 'package:intl/intl.dart';
Future<List<ipoData>> fetchIPODatas(http.Client client) async {
final response = await client.get('http://realchord.net/ipo/getIPOData.php');
// Use the compute function to run parseIpoData in a separate isolate.
return compute(parseIpoData, response.body);
}
// A function that converts a response body into a List<Photo>.
List<ipoData> parseIpoData(String responseBody) {
final parsed = jsonDecode(responseBody).cast<Map<String, dynamic>>();
return parsed.map<ipoData>((json) => ipoData.fromJson(json)).toList();
}
// ignore: camel_case_types
class ipoData {
final String ipoDate;
final String company;
ipoData({this.ipoDate, this.company});
factory ipoData.fromJson(Map<String, dynamic> json) => ipoData(
ipoDate: json['date'],
company: json['company'],
);
}
// factory Model.fromJson(Map<String, dynamic> json) => Model(
// value1: json['key1'],
// value2: json['key2'],
// value3: json['key3'],
// value4: json['key4'],
// );
void main() => runApp(new MyApp());
class MyApp extends StatelessWidget {
// This widget is the root of your application.
@override
Widget build(BuildContext context) {
return new MaterialApp(
title: 'IPO calendar',
theme: new ThemeData(
primarySwatch: Colors.blue,
),
home: new MyHomePage(title: 'IPO calendar'));
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
@override
_MyHomePageState createState() => new _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
DateTime _currentDate = new DateTime.now();
DateTime _currentDate2 = new DateTime.now();
String _currentMonth = DateFormat.MMMM().format(new DateTime.now());
DateTime _next = new DateTime(
DateTime.now().year, DateTime.now().month + 1, DateTime.now().day);
DateTime _prev = new DateTime(
DateTime.now().year, DateTime.now().month - 1, DateTime.now().day);
String _nextMonth;
String _prevMonth;
DateTime _targetDateTime = new DateTime.now();
// List<DateTime> _markedDate = [DateTime(2018, 9, 20), DateTime(2018, 10, 11)];
EventList<Event> _markedDateMap = new EventList<Event>();
// ignore: unused_field
CalendarCarousel _calendarCarouselNoHeader;
// load data
@override
void initState() {
super.initState();
}
// List response = await fetchIPODatas(http.Client());
@override
Widget build(BuildContext context) {
/// Example Calendar Carousel without header and custom prev & next button
_calendarCarouselNoHeader = CalendarCarousel<Event>(
onDayPressed: (DateTime date, List<Event> events) {
this.setState(() => _currentDate2 = date);
// events.forEach((event) => print(event.title));
},
//달력 기본 설정
daysHaveCircularBorder: true,
showOnlyCurrentMonthDate: false,
showHeader: false,
customGridViewPhysics: NeverScrollableScrollPhysics(),
height: 500.0,
daysTextStyle: TextStyle(
fontWeight: FontWeight.w600,
color: Colors.white, //weekend day font color
),
weekendTextStyle: TextStyle(
fontWeight: FontWeight.w600,
color: Colors.white, //weekend day font color
),
weekdayTextStyle: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
),
// thisMonthDayBorderColor: Colors.grey, // border color of each day
weekFormat: false,
// firstDayOfWeek: 4,
markedDatesMap: _markedDateMap,
selectedDateTime: _currentDate2,
targetDateTime: _targetDateTime,
minSelectedDate: _currentDate.subtract(Duration(days: 360)),
maxSelectedDate: _currentDate.add(Duration(days: 360)),
// //이벤트가 있는 날에 대한 설정
// markedDateCustomShapeBorder:
// CircleBorder(side: BorderSide(color: Colors.yellow)),
markedDateCustomTextStyle: TextStyle(
fontSize: 30,
color: Colors.white,
),
// markedDateIconBorderColor: Colors.white,
// markedDateMoreShowTotal: true,
//오늘에 대한 설정
todayTextStyle: TextStyle(
color: Colors.white,
),
todayButtonColor: Colors.white24,
todayBorderColor: null,
// 선택한 날에 대한 설정
selectedDayTextStyle: TextStyle(
color: Colors.black,
),
selectedDayButtonColor: Colors.white,
// selectedDayBorderColor: Colors.white,
// 지난 달에 대한 설정
prevDaysTextStyle: TextStyle(
fontSize: 16,
color: Colors.white38,
),
// 다음 달에 대한 설정
nextDaysTextStyle: TextStyle(
fontSize: 16,
color: Colors.white38,
),
inactiveDaysTextStyle: TextStyle(
color: Colors.white38,
fontSize: 16,
),
onCalendarChanged: (DateTime date) {
this.setState(() {
_targetDateTime = date;
_currentMonth = DateFormat.MMMM().format(_targetDateTime);
_next = new DateTime(_targetDateTime.year, _targetDateTime.month + 1,
_targetDateTime.day);
_nextMonth = DateFormat.MMMM().format(_next);
_prev = new DateTime(_targetDateTime.year, _targetDateTime.month - 1,
_targetDateTime.day);
_prevMonth = DateFormat.M().format(_prev);
});
},
onDayLongPressed: (DateTime date) {
print('long pressed date $date');
},
);
_markedDateMap.clear();
_nextMonth = DateFormat.MMMM().format(_next);
_prevMonth = DateFormat.M().format(_prev);
// dotColorList.add(Colors.white);
return new Scaffold(
body: FutureBuilder<List<ipoData>>(
future: fetchIPODatas(http.Client()),
builder: (context, snapshot) {
if (snapshot.hasError) print(snapshot.error);
if (snapshot.connectionState == ConnectionState.done &&
snapshot.hasData &&
snapshot.data != null) {
final List<ipoData> ipoDataList = snapshot.data;
for (var i = 0; i < snapshot.data.length; i++) {
DateTime dt = DateTime.parse(ipoDataList[i].ipoDate.toString());
_markedDateMap.add(
dt,
new Event(
date: dt,
title: ipoDataList[i].company,
dot: Container(
margin: EdgeInsets.symmetric(horizontal: 1.0),
color: Colors.red.shade300,
height: 5.0,
width: 5.0,
),
));
}
}
return snapshot.hasData && _markedDateMap.events.length > 0
? SingleChildScrollView(
child: Stack(children: [
Container(
padding: EdgeInsets.only(top: 50),
color: Colors.blue,
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
//custom icon without header
Container(
//display Month
margin: EdgeInsets.only(
top: 20.0,
bottom: 16.0,
left: 0.0,
right: 0.0,
),
padding: EdgeInsets.all(0),
child: new Row(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
FlatButton(
padding: EdgeInsets.all(0),
child: Text(_prevMonth,
// softWrap: false,
maxLines: 1,
textAlign: TextAlign.right,
style: TextStyle(
color: Colors.white12,
fontSize: 48,
fontWeight: FontWeight.bold,
)),
onPressed: () {
setState(() {
_targetDateTime = DateTime(
_targetDateTime.year,
_targetDateTime.month - 1);
_currentMonth = DateFormat.MMMM()
.format(_targetDateTime);
});
},
),
Text(
_currentMonth,
maxLines: 1,
style: TextStyle(
color: Colors.white,
fontWeight: FontWeight.bold,
fontSize: 48.0,
),
),
FlatButton(
child: Text(
_nextMonth,
softWrap: true,
maxLines: 1,
style: TextStyle(
color: Colors.white12,
fontSize: 48,
fontWeight: FontWeight.bold,
),
),
onPressed: () {
setState(() {
_targetDateTime = DateTime(
_targetDateTime.year,
_targetDateTime.month + 1);
_currentMonth = DateFormat.MMMM()
.format(_targetDateTime);
_next = new DateTime(
_targetDateTime.year,
_targetDateTime.month + 1,
_targetDateTime.day);
_nextMonth =
DateFormat.MMMM().format(_next);
_prev = new DateTime(
_targetDateTime.year,
_targetDateTime.month - 1,
_targetDateTime.day);
_prevMonth = DateFormat.M().format(_prev);
});
},
)
],
),
),
Container(
margin: EdgeInsets.symmetric(horizontal: 16.0),
child: _calendarCarouselNoHeader,
)
],
),
),
Container(
height: MediaQuery.of(context).size.height - 500,
width: MediaQuery.of(context).size.width,
margin: const EdgeInsets.only(top: 500),
padding: const EdgeInsets.only(
top: 40,
left: 15,
),
decoration: BoxDecoration(
borderRadius: BorderRadius.circular(50),
color: Colors.white,
),
child: Column(
children: [
EventItem(
company: "LGENSol",
)
],
),
)
]),
)
: Center(child: CircularProgressIndicator());
},
));
}
}
class EventItem extends StatefulWidget {
// final Icon icon;
final String company;
// final Text category;
// final Function() notifyParent;
EventItem(
{
// @required this.icon,
@required this.company}); //@required this.notifyParent
@override
_EventItemState createState() => _EventItemState();
}
class _EventItemState extends State<EventItem> {
get futureAlbum => null;
@override
Widget build(BuildContext context) {
return Column(
children: <Widget>[
Row(
children: [
Icon(
Icons.favorite,
color: Colors.pink,
size: 24.0,
),
Padding(
padding: EdgeInsets.all(12.0),
child: Text(widget.company,
style: TextStyle(
fontWeight: FontWeight.bold,
fontSize: 20,
)),
),
Padding(
padding: EdgeInsets.all(5.0),
child: Text("(청약)",
style: TextStyle(
fontWeight: FontWeight.bold,
fontSize: 20,
)),
),
],
),
Row(
children: [
Padding(
padding: EdgeInsets.only(left: 37),
child: Text("공모가:20,000원 | 상장:8/20 | 주관:키움",
style: TextStyle(
fontSize: 20,
)),
),
],
)
],
);
}
}
答案 0 :(得分：0)
每次您在有状态小部件中调用 setState 时，您都在调用该小部件的构建方法，并且由于您的 FutureBuilder 是其中的一部分，因此它将被调用。您似乎并没有改变未来，所以我建议您可以将 FutureBuilder 提高一个级别，并将您的有状态小部件放入 FutureBuilder
class MyHomePage extends StatelessWidget {
@override
Widget build(BuildContext context) {
return Scaffold(
body: FutureBuilder(
future: fetchIPODatas(http.Client()),
builder: (context, snapshot) {
//... (add your extracted stateful widget in here..)
},
),
);
}
}