Flutter: Snapshot isn't showing data - api

I create a Listview builder with get method (API call). API call is fine, cause I get response. But in widget snapshot.data show me null. I can't fixed this problem and don't why it's behaving like this. Please someone help me.
API responsebody
Here is my code for API call
class APIService {
Future<List<EducationInfo>> getEducationInfo() async {
String url = "$baseAPIUrl/educations";
String _token = await SavedData().loadToken();
String authorization = "Bearer $_token";
var response = await http.get(url, headers: {
'Content-Type': 'application/json',
'Accept': 'application/json',
"Authorization": authorization
});
print('API ${response.statusCode}\n API${json.decode(response.body)}');
if (response.statusCode == 200) {
var jsonResponse = response.body;
var decoded = json.decode(jsonResponse);
return decoded['success']
.map<EducationInfo>((b) => EducationInfo.fromJson(b))
.toList();
} else {
throw Exception('Failed to load Education Information');
}
}
}
Here is my Model.dart
//Model
class EducationInfo {
int id;
String degreeName;
int rollNumber;
int regNumber;
int passingYear;
String gradeType;
double cgpa;
double outOfCgpa;
String divisionName;
String groupName;
String subjectName;
String boardName;
String instituteName;
EducationInfo({
this.id,
this.degreeName,
this.rollNumber,
this.regNumber,
this.passingYear,
this.gradeType,
this.cgpa,
this.outOfCgpa,
this.divisionName,
this.groupName,
this.subjectName,
this.boardName,
this.instituteName,
});
factory EducationInfo.fromJson(Map<String, dynamic> json) {
return EducationInfo(
id: json['user_id'],
degreeName: json['degree_name'],
rollNumber: json['roll_number'],
regNumber: json['registration_number'],
passingYear: json['passing_year'],
gradeType: json['grade_type'],
cgpa: json['cgpa'],
outOfCgpa: json['out_of_cgpa'],
divisionName: json['division'],
groupName: json['group_name'],
subjectName: json['subject_name'],
boardName: json['board'],
instituteName: json['institute_name'],
);
}
}
And here is my main code-
class Resume extends StatefulWidget {
#override
_ResumeState createState() => _ResumeState();
}
class _ResumeState extends State<Resume> {
Future<List<EducationInfo>> furuteEducationInfo;
#override
void initState() {
super.initState();
furuteEducationInfo = APIService().getEducationInfo();
}
#override
Widget build(BuildContext context) {
return Scaffold(
resizeToAvoidBottomPadding: false,
appBar: AppBar(
automaticallyImplyLeading: false,
leading: IconButton(
icon: Icon(
Icons.arrow_back_ios,
),
onPressed: () {
Navigator.pop(context);
},
),
title: Text("Resume"),
),
body: Align(
child: FutureBuilder(
future: furuteEducationInfo,
builder: (context, snapshot) {
var educationInfo = snapshot.data;
if (snapshot.data == null) {
return Text("No Data Available ");
} else if (snapshot.hasData) {
return ListView.builder(
scrollDirection: Axis.vertical,
itemCount: educationInfo.length,
itemBuilder: (context, index) {
var eduInfo = educationInfo[index];
print(
"\nEducation Info ${educationInfo[index]}");
return designedContainer(
_width - 30,
Padding(
padding: EdgeInsets.all(5.0),
child: Stack(
children: [
Container(
child: Column(
children: [
detailsField(
"Degree Name",
"${_checkNull(eduInfo.degreeName)}"),
],
),
),
Align(
alignment:
Alignment.topRight,
child: editButton(
Icons.add, "Delete",
() {
print("Delete");
}),
)
],
),
));
});
} else {
Text("Something Went to Wrong");
}
}),
),
);
}
And here is also postman Screenshot-

in your EducationInfo.fromJson method
replace
cgpa: json['cgpa'] ?? 0.0,
outOfCgpa: json['out_of_cgpa'] ?? 0.0,

Since it is a future and runs Asynchronously you have to check if the snapshot has data, and wait for the data to be fetched. Following a snippet code how you would check for that inside your build method:
(snapshot.hasData && snapshot.data.length == 0)
? Container(
child: Center(
child: Column(
mainAxisSize: MainAxisSize.max,
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text("Congrats, No jobs asssigned!!!")
],
),
),
)
: (snapshot.hasData)
? Container(
child: ListView.builder(
.....)

Related

Flutter: A non-null String must be provided to a Text widget. Failed assertion: line 378 pos 10: 'data != null'

I getting data from API and adding it to data table, it's working fine, when i select month from dropdown, my data table get modify according to selected month from drop down, but initially it print this error.
and its change to this when i select month from dropdown
here is code
class MyAttendance extends StatefulWidget {
#override
_MyAttendanceState createState() => _MyAttendanceState();
}
class _MyAttendanceState extends State<MyAttendance> {
//List<History> _historyList;
List<History> historyList=[];
String _selectedLeave;
int monthIndex;
int month;
var monthsList=<String>[
'January',
'Febuary',
'March',
'April',
'May',
'June',
'July',
'Augest',
'September',
'October',
'November',
'December'
];
String getdate="";
void _getDate() {
final String formattedDateTime =
DateFormat('MM').format(DateTime.now()).toString();
setState(() {
getdate = formattedDateTime;
print("date "+getdate);
});
}
_userDetails() async{
SharedPreferences myPrefs=await SharedPreferences.getInstance();
setState(() {
getname=myPrefs.getString('name');
});
}
void initState() {
_userDetails();
_getDate();
_getRecord();
}
Future<List<History>> _getRecord() async{
Dio dio=new Dio();
var data={
'username':getname,
'month':month
};
return dio
.post(localhostUrlAttendanceHistory,data: json.encode(data))
.then((onResponse) async {
var jsonData=onResponse.data['data'];
//List<History> historyList = [];
for (var h in jsonData) {
History history = History(
h["Date"],
h["TimeIn"],
h["TimeOut"],
);
historyList.add(history);
}
return historyList;
})
.catchError((onerror){
print(onerror.toString());
});
}
Widget attendanceHistory(List<History>
historyList)=>
DataTable(columns: <DataColumn>[
DataColumn(label: Text("Date"),),
DataColumn(label: Text("Time in" ),),
DataColumn(label: Text("Time out")
)],
rows:
historyList
?.map((element)=>DataRow(
cells: <DataCell>[
DataCell(Text(element?.date)),
DataCell(Text(element?.timeIn)),
DataCell(Text(element?.timeOut)),
]) )?.toList());
TextEditingController fromDate=new TextEditingController();
TextEditingController toDate=new TextEditingController();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: new MyAppBar(title: Text("My Attendance"),onpressed: (){
Navigator.push(context, MaterialPageRoute(builder: (context)=>Profile()));
}),
drawer:Emp_DrawerCode(),
body:Stack(children: <Widget>[
Container(
padding: EdgeInsets.fromLTRB(25, 15, 0, 0),
child: Text("Attendance history",style: TextStyle(fontSize: 30,color: Colors.blue[900],fontWeight: FontWeight.bold),),
),
Container(
padding: EdgeInsets.fromLTRB(45, 80, 10, 0),
child:
DropdownButton<String>(
value: _selectedLeave==null?null:monthsList[monthIndex],
items:
monthsList
.map<DropdownMenuItem<String>>((String value) {
return DropdownMenuItem<String>(
value: value,
child: Text(value)
);
}).toList(),
hint:Text(
"Please choose a month",
),
onChanged: (String value) {
setState(() {
_selectedLeave=value;
monthIndex = monthsList.indexOf(value);
month=monthIndex+1;
print(month);
print(_selectedLeave);
});
},
),
),
Container(
padding: EdgeInsets.fromLTRB(15, 150, 0, 0),
child:SingleChildScrollView(
scrollDirection: Axis.vertical,
child: FutureBuilder(
future: _getRecord(),
builder: (BuildContext context, AsyncSnapshot<List<History>> snapshot) {
// Check if the data has been received.
if (snapshot.hasData) {
// Return the widget and provide the received data.
return attendanceHistory(snapshot.data);
}
return Center(child: CircularProgressIndicator(),);
// print("data");
// print(snapshot.data);
// Text("No data is shown");
//return attendanceHistory(snapshot.data);
}
),
),)
]));
}
}
class History {
final String date;
final String timeIn;
final String timeOut;
History(this.date, this.timeIn, this.timeOut);
}
Error
════════ Exception caught by widgets library ═══════════════════════════════════
A non-null String must be provided to a Text widget.
'package:flutter/src/widgets/text.dart':
Failed assertion: line 378 pos 10: 'data != null'
The relevant error-causing widget was
FutureBuilder<List<History>>
lib\My_Attendance\MyAttendance.dart:171
Update:
After few seconds of red screen error, it display this, and i have not select month from dropdown too.
and it sends this error now
════════ Exception caught by widgets library ═══════════════════════════════════
The method 'map' was called on null.
Receiver: null
Tried calling: map<DataRow>(Closure: (History) => DataRow)
The relevant error-causing widget was
FutureBuilder<List<History>>
Update
Error:
Update:
builder: (BuildContext context, AsyncSnapshot<List<History>> snapshot) {
// Check if the data has been received.
if(snapshot.connectionState==ConnectionState.done){
if (snapshot.hasData) {
return Center(
child: Text('${snapshot.error} occured',
style: TextStyle(fontSize: 18)),
);
}
else if(snapshot.hasData){
return attendanceHistory(snapshot.data);
}
// Return the widget and provide the received data.
//return Center(child: CircularProgressIndicator(),);
}
//return attendanceHistory(snapshot.data);
return Center(child: CircularProgressIndicator(),);
// print("data");
// print(snapshot.data);
// Text("No data is shown");
}
),
kindly please help how i can fix it?
A better practice is to use loader while fetching the data from API. Since future builder has a property to check whether there is response from API or not. TO check this simply use
`FutureBuilder(
future: _getRecord(),
builder: (BuildContext context,
AsyncSnapshot<List<History>> snapshot) {
// Below line will check whether future has data or not
if (snapshot.connectionState == ConnectionState.done) {
// If we got an error
if (snapshot.hasError) {
return Center(
child: Text(
'${snapshot.error} occured',
style: TextStyle(fontSize: 18),
),
);
// if we got our data
} else if (snapshot.hasData) {**strong text**
if (snapshot.hasData) {
return attendanceHistory(snapshot.data);
}
return Center(child: CircularProgressIndicator(),);
}`
Or else you can use null aware operator to handle the null value as below.
Widget attendanceHistory(List<History>
historyList)=>
DataTable(columns: <DataColumn>[
DataColumn(label: Text("Date"),),
DataColumn(label: Text("Time in" ),),
DataColumn(label: Text("Time out")
)],
rows:
historyList
?.map((element)=>DataRow(
cells: <DataCell>[
DataCell(Text(element?.date)),
DataCell(Text(element?.timeIn)),
DataCell(Text(element?.timeOut)),
])
)?.toList());
This error generate when you pass a null value to Text widget. So to avoid this either you can put a null check condition before displaying text or you can pass a default value to the Text widget.
Widget attendanceHistory(List<History> historyList)=>
DataTable(columns: <DataColumn>[
DataColumn(label: Text("Date"),),
DataColumn(label: Text("Time in" ),),
DataColumn(label: Text("Time out")
)],
rows:
historyList
.map((element)=>DataRow(
cells: <DataCell>[
DataCell(Text(element.date ?? "N/A")),
DataCell(Text(element.timeIn ?? "N/A")),
DataCell(Text(element.timeOut ?? "N/A")),
])
).toList());
Display CircularProgressIndicator while fetching the records.
Container(
padding: EdgeInsets.fromLTRB(15, 150, 0, 0),
child:SingleChildScrollView(
scrollDirection: Axis.vertical,
child: FutureBuilder( //This is line 171
future: _getRecord(),
builder: (BuildContext context, AsyncSnapshot<List<History>> snapshot) {
// Check if the data has been received.
if (snapshot.hasData) {
// Return the widget and provide the received data.
return attendanceHistory(snapshot.data);
}
return Center(child: CircularProgressIndicator(),);
}
),

API data display - flutter card widget

Get API connection is successful. but I have no idea how to map data.. how is connect snapshot.data,
I want to display data in a Stack widget.
https://flutter.dev/docs/cookbook/networking/fetch-data
I learned this from the association with this source
Future<News> fetchNews() async {
final response =
await http.get('#url');
print(response.body);
if (response.statusCode == 200) {
return News.fromJson(jsonDecode(response.body));
} else {
throw Exception('Failed to load news');
}
}
class News {
final String title;
final String description;
final String image;
News({this.title, this.description, this.image});
factory News.fromJson(Map<String, dynamic> json) {
return News(
title: json['title'],
description: json['description'],
image: json['image'],
);
}
}
Widget _buildPage(BuildContext context, int direction) {
Size size = MediaQuery.of(context).size;
return SafeArea(
child: FutureBuilder<News>(
future: futureNews,
builder: (context, snapshot) {
if (snapshot.hasData) {
return newsCard(snapshot.data);
} else if (snapshot.hasError) {
return Text("${snapshot.error}");
}
return CircularProgressIndicator();
},
),
);
}
Widget newsCard(size){
return Stack(
children: <Widget>[
Container(
child: Image.network(
image,
fit: BoxFit.cover
),
height: size.height/2.0,
),
),
],
);
}
Your code is a bit messy and it doesn't make much sense. It seems obvious that the data is not getting displayed because you're passing your News object to your newsCard function, but the parameter seems to be expecting Size. I also don't know where are you getting the image property from since it doesn't seem to be declared anywhere in the code.
Doing some changes to your code, a minimal working function that returns your widget would look like this:
Widget _buildPage(BuildContext context, int direction) {
Size size = MediaQuery.of(context).size;
return SafeArea(
child: FutureBuilder<News>(
future: futureNews,
builder: (context, snapshot) {
if (snapshot.hasData) {
return newsCard(snapshot.data, size);
} else if (snapshot.hasError) {
return Text("${snapshot.error}");
}
return CircularProgressIndicator();
},
),
);
}
Widget newsCard(News news, Size size){
return Stack(
children: <Widget>[
Container(
child: Image.network(
news.image,
fit: BoxFit.cover
),
height: size.height/2.0,
),
),
],
);
}
UPDATE
If you're getting the error you mentioned bellow, is likely that your response from the get request is a list of News and not just one News object, therefore you'll have to change this:
return News.fromJson(jsonDecode(response.body));
To this:
return jsonDecode(response.body).map<News>((object) => News.fromJson(object)).toList();
The return type of fetchNews() should be Future<List<News>> instead of Future<News>

Flutter app error "NoSuchMethodError: The getter 'length' was called on null"

Am getting this error and can't find the why, the app shows a google map calling hospital from google map places api, api call returns fine when used in chrome, but the app fail to build showing the "NoSuchMethodError: The getter 'length' was called on null" error. Thanks for your help.
class Search extends StatelessWidget {
#override
Widget build(BuildContext context) {
final currentPosition = Provider.of<Position>(context);
final placesProvider = Provider.of<Future<List<Place>>>(context);
return FutureProvider(
create: (context) => placesProvider,
child: Scaffold(
body: (currentPosition != null)
? Consumer<List<Place>>(
builder: (_, places, __) {
return Column(
children: <Widget>[
Container(
height: MediaQuery.of(context).size.height / 3,
width: MediaQuery.of(context).size.width,
child: GoogleMap(
initialCameraPosition: CameraPosition(
target: LatLng(currentPosition.latitude,
currentPosition.longitude),
zoom: 16.0),
zoomGesturesEnabled: true,
mapToolbarEnabled: true,
myLocationEnabled: true,
scrollGesturesEnabled: true,
),
),
SizedBox(
height: 10.0,
),
Expanded(
child: ListView.builder(
itemCount: places.length,
itemBuilder: (context, index) {
return Card(
child: ListTile(
title: Text(places[index]?.name),
),
);
}),
)
],
);
},
)
: Center(
child: CircularProgressIndicator(),
),
),
);
}
}
The api request works fine when called in chrome, problem is when building the app. This is my places_service.dart file:
class PlacesService {
final key = 'xxxxxxxxxxxxxxxxxxxxx-ttttttttttttttttt';
Future<List<Place>> getPlaces(double lat, double lng) async {
var response = await http.get('https://maps.googleapis.com/maps/api/place/nearbysearch/json?location=$lat,$lng&type=hospital&rankby=distance&key=$key');
var json = convert.jsonDecode(response.body);
var jsonResults = json['results'] as List;
return jsonResults.map((place) => Place.fromJson(place)).toList();
}
}
Problem is this line:
itemCount: places.length,
If you use constructions like places.length the programming code can fail on two places:
when places = null
when places.length = null (your situation)
You cannot call methods and properties on null-objects; that is why you get this error. So before you call places.length you must be sure that both situations cannot occur. How this is done and if the check is really necessary depends on the rest of your program. One way to check is:
itemCount: places.length != null ? places.length : 0;

Why doesn't my FutureBuilder return any data?

I have a api that returns a list of data.
When I retrieve that data I use a FutureBuilder to show the list of data.
But for some reason it won't show my data even though when I print the response I can see that I got a correct response.
This is the error that i got:
══╡ EXCEPTION CAUGHT BY WIDGETS LIBRARY ╞═══════════════════════════════════════════════════════════
I/flutter (11846): The following assertion was thrown building FutureBuilder<List<BasicDiskInfo>>(dirty, state:
I/flutter (11846): _FutureBuilderState<List<BasicDiskInfo>>#a0948):
I/flutter (11846): A build function returned null.
I/flutter (11846): The offending widget is: FutureBuilder<List<BasicDiskInfo>>
I/flutter (11846): Build functions must never return null. To return an empty space that causes the building widget to
I/flutter (11846): fill available room, return "new Container()". To return an empty space that takes as little room as
I/flutter (11846): possible, return "new Container(width: 0.0, height: 0.0)".
I don't know what to do. Help me?
API
static Future<List<BasicDiskInfo>> fetchAllDisks() async {
final response = await http.get('link');
if (response.statusCode == 200) {
Iterable list = json.decode(response.body);
var disks = new List<BasicDiskInfo>();
disks = list.map((model) => BasicDiskInfo.fromJson(model)).toList();
print(disks[0]);
return disks;
} else {
throw Exception('Failed to load disks');
}
}
Page
class Disks extends StatelessWidget {
#override
Widget build(BuildContext context) {
return FutureBuilder(
future: API.fetchAllDisks(),
builder: (BuildContext context, AsyncSnapshot snapshot) {
switch (snapshot.connectionState) {
case ConnectionState.none:
case ConnectionState.waiting:
return new CircularProgressIndicator();
default:
if (snapshot.hasError) {
return new Text('Error: ${snapshot.error}');
} else {
print(snapshot.data);
createListView(context, snapshot);
}
}
},
);
}
Widget createListView(BuildContext context, AsyncSnapshot snapshot) {
List<BasicDiskInfo> disks = snapshot.data;
return new ListView.builder(
itemCount: disks.length,
itemBuilder: (context, index) {
return GestureDetector(
onTap: () {
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => SpecificDiskPage(
diskId: disks[index].id,
),
));
},
child: Card(
child: Column(
children: <Widget>[
Row(
children: <Widget>[
Text(disks[index].name),
Spacer(),
Text(disks[index].driveType),
Spacer(),
Text(disks[index].driveFormat),
],
),
Row(
children: <Widget>[
Text(disks[index].totalSize.toString()),
Spacer(),
Text(disks[index].totalFreeSpace.toString()),
],
),
],
),
),
);
},
);
}
}
BasicDiskInfo
class BasicDiskInfo {
int id;
String name;
String driveType;
String driveFormat;
int totalSize;
int totalFreeSpace;
BasicDiskInfo(
{this.id,
this.name,
this.driveType,
this.driveFormat,
this.totalSize,
this.totalFreeSpace});
factory BasicDiskInfo.fromJson(Map<String, dynamic> json) {
return BasicDiskInfo(
id: json['id'],
name: json['name'],
driveType: json['driveType'],
driveFormat: json['driveFormat'],
totalSize: json['totalSize'],
totalFreeSpace: json['totalFreeSpace']);
}
}
The FutureBuilder should return a list with the data from the api
There is an error in your build method. You didn't return createListView(context, snapshot); in your default case.

Flutter Shared Preferences saving values, not displaying

I have a list of courses. The user marks each course complete using a checkbox on the ListTile.
I implemented Shared Preferences so the list of completed courses persists when the user closes the app.
The values are saving, but when the app is closed (in the emulator or through the IDE) and reopened, the UI shows the value as false (Even when the Terminal says the value is True).
When I hot restart, the UI shows the value as True (Which was expected from the start). I haven't been able to get the UI to show correctly using the emulator buttons or on a device.
How can I get the UI to show the values correctly right away?
SharedPreferences prefs;
void getResult(Course course) async {
prefs = await SharedPreferences.getInstance();
results[course.courseResult] = prefs.getBool(course.courseResult) ?? false;
print('${course.courseTitle} Result: ${results[course.courseResult]}');
setState(() {
results[course.courseResult];
});
}
Future<bool> setResult(Course course) async {
prefs = await SharedPreferences.getInstance();
print ('${course.courseTitle} SET TO ${results[course.courseResult]}');
return prefs.setBool(course.courseResult, results[course.courseResult]);
}
initState() {
super.initState();
getResult(widget.entry);
}
Future onChanged(bool value, Course course) {
setState(() {
results[course.courseResult] = value;
});
return setResult(course);
}
Here is the full code (Though I did shorten the lists for space purposes, and left out the pages that aren't affected by this error...)
import 'package:flutter/material.dart';
import 'main.dart';
import 'CourseList.dart';
import 'package:shared_preferences/shared_preferences.dart';
import 'dart:async';
import 'package:url_launcher/url_launcher.dart';
import 'package:intl/intl.dart';
class LearningPlan extends StatefulWidget{
LearningPlanState createState() => new LearningPlanState();
}
class LearningPlanState extends State<LearningPlan> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: MyAppBar(
title: Text('Learning Plan'),
),
drawer: MyDrawer(),
body: ListView.builder(
itemBuilder: (BuildContext context, int index) =>
new CourseTile(courseList[index]),
itemCount: courseList.length,
),
);
}
}
class CourseTile extends StatefulWidget {
CourseTile(this.entry);
final Course entry;
CourseTileState createState() => new CourseTileState();
}
class CourseTileState extends State<CourseTile> {
//Detail Card
Future<Null> _launched; // ignore: unused_field
Future<Null> _launchInWebViewOrVC(String url) async {
if (await canLaunch(url)) {
await launch(url, forceSafariVC: false, forceWebView: false);
} else {
throw 'Could not launch $url';
}
}
Widget selfDirectedURL(Course course) {
if (course.courseMethod == 'Self-Directed') {
return new IconButton(
icon: Icon(Icons.cloud_download),
onPressed: () => setState(() {
_launched = _launchInWebViewOrVC(course.courseURL);
}),
);
} else {
return new Container();
}
}
Future<Null> courseDetails(Course course) async {
await showDialog(
context: context,
child: new SimpleDialog(
title: Text(course.courseTitle),
children: <Widget>[
Stack(
children: <Widget>[
Center(child: Image.asset(course.courseImage,
colorBlendMode: BlendMode.lighten,
color: fkBlue25,
height: 200.0,
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Text(course.courseDescription),
),
],
),
Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children: <Widget>[
selfDirectedURL(course),
FlatButton(
onPressed: (){
Navigator.pop(context);
},
child: Text('OK'),
),
],
),
],
));
}
//CheckBox Constructors
SharedPreferences prefs;
void getResult(Course course) async {
prefs = await SharedPreferences.getInstance();
results[course.courseResult] = prefs.getBool(course.courseResult) ?? false;
print('${course.courseTitle} Result: ${results[course.courseResult]}');
setState(() {
results[course.courseResult];
});
}
Future<bool> setResult(Course course) async {
prefs = await SharedPreferences.getInstance();
print ('${course.courseTitle} SET TO ${results[course.courseResult]}');
return prefs.setBool(course.courseResult, results[course.courseResult]);
}
initState() {
super.initState();
getResult(widget.entry);
}
Future onChanged(bool value, Course course) async {
final result = await setResult(course);
setState(() {
results[course.courseResult] = value;
});
return result;
}
//Main Tile
Widget buildTiles(Course course) {
return Card(
shape: Border.all(
color: fkBlue,
),
margin: EdgeInsets.all(16.0),
elevation: 8.0,
child: Padding(
padding: const EdgeInsets.all(8.0),
child: ListTile(
title: Text(course.courseTitle),
subtitle: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text(course.courseCode),
Text(course.courseMethod)
],
),
leading: SizedBox(
height: 60.0,
width: 60.0,
child: Image.asset(course.courseImage)),
trailing: Column(
children: <Widget>[
Text(results[course.courseResult] ? 'Complete' : 'Incomplete',
),
Checkbox(
value: results[course.courseResult],
onChanged: (bool value) {
onChanged(value, course);
if (value == true) {
snackBarCompleted(course);
} else {
snackBarUnCompleted(course);
}
},
),
]
),
onTap: () {
courseDetails(course);
}
),),
);
}
#override
Widget build(BuildContext context) {
return buildTiles(widget.entry);
}
void snackBarCompleted(course) {
Scaffold.of(context).showSnackBar(
SnackBar(content: Text(
'${course.courseTitle} completed on ${DateFormat.yMd().format(DateTime.now()).toString()}'
),
backgroundColor: fkBlue,
duration: Duration(seconds: 3),
),
);
}
void snackBarUnCompleted(course) {
Scaffold.of(context).showSnackBar(
SnackBar(content: Text('${course.courseTitle} no longer marked \"Complete\"'
),
duration: Duration(seconds: 3),
),
);
}
}
//Learning Schedule Page
class LearningSchedule extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: MyAppBar(
title: Text('Schedule'),
),
drawer: MyDrawer(),
body: ListView.builder(
itemBuilder: (BuildContext context, int index) =>
new LearningScheduleBuilder(courseList[index]),
itemCount: courseList.length,
),
);
}
}
class LearningScheduleBuilder extends StatelessWidget {
LearningScheduleBuilder(this.entry);
final Course entry;
Widget buildList (Course course) {
return Text(course.courseTitle,
style: new TextStyle(color: results[course.courseResult] ? Colors.grey : fkBlue),);
}
#override
Widget build(BuildContext context) {
return buildList(entry);
}
}
final List<Course> courseList = <Course>[
new Course(
courseTitle: 'Company Orientation',
coursePreReq: 'N/A',
courseCode: 'HR',
courseURL: '',
courseMethod: 'Facilitator-Led',
courseImage: 'assets/courseImage/logo.png',
courseDescription:
'Company overview; Benefits package and documents; Ethics and Compliance Training, Introduction to learning programs; Computer orientation; Lab tour; Safety training.',
courseAudience: 'BCAE BCCC ITAE ITCC TCTAE TCTCC PlasmaCC PlasmaAE',
courseResult: 'result1',
),
new Course(
courseTitle: 'Intro to Learning Program',
coursePreReq: 'N/A',
courseCode: 'Nicole Asma',
courseURL: '',
courseMethod: 'Facilitator-Led',
courseImage: 'assets/courseImage/logo.png',
courseDescription:
'Overview of onboarding program; Components of North America University; Support available for all learning units; introduction to Learning and Development Team Overview of WebEx calls.',
courseAudience: 'BCAE BCCC ITAE ITCC TCTAE TCTCC PlasmaCC PlasmaAE',
courseResult: 'result2',
),
class Course {
final String courseTitle;
final String coursePreReq;
final String courseCode;
final String courseDescription;
final String courseImage;
final String courseMethod;
final String courseURL;
final String courseAudience;
final String courseResult;
const Course({
this.courseTitle,
this.coursePreReq,
this.courseCode,
this.courseDescription,
this.courseImage,
this.courseMethod,
this.courseURL,
this.courseAudience,
this.courseResult,
});
Course.fromMap(Map<String, dynamic> map)
: courseTitle = map['courseTitle'],
coursePreReq = map['coursePreReq'],
courseCode = map['courseCode'],
courseDescription = map['courseDescription'],
courseImage = map['roocourseImagem'],
courseMethod = map['courseMethod'],
courseURL = map['courseURL'],
courseAudience = map['courseAudience'],
courseResult = map['courseResult'];
}
Map results = {
'result1': false,
'result2': false,
'result3': false,
'result4': false,
Could you make this little change? :
Change this :
Future onChanged(bool value, Course course) {
setState(() {
results[course.courseResult] = value;
});
return setResult(course);
}
To this:
Future onChanged(bool value, Course course) async {
final result = await setResult(course);
setState(() {
results[course.courseResult] = value;
});
return result;
}
UPDATE
Replace your initState method with this:
_onLayoutDone(_){
getResult(widget.entry);
}
#override
void initState() {
WidgetsBinding.instance.addPostFrameCallback(_onLayoutDone);
super.initState();
}