I am using WorkManager to make my flutter app run in background too, but it doesn't seems to work. I am using stream builder to fetch api and a audio plugin to play audio every time there is new entry but i also wanted this to work even when the app is closed so i used WorkManager . But it is not working, the app is only working when it is opened.
this is my code
class net{
static Stream<http.Response> getRandomNumberFact() async* {
yield* Stream.periodic(const Duration(seconds: 5), (_) {
return http.get(Uri.parse("https://script.google.com/macros/s/AKfycbwhbpF4ZxuMUcTZZvObAqvE1pAbEfPt7gZHRV1vVp8PuKt39-ouOm-kQJ1U1LtlEwV-/exec"));
}).asyncMap((event) async => await event);
}
}
void callbackDispatcher(){
Workmanager().executeTask((taskName, inputData) {
net.getRandomNumberFact();
return Future.value(true); });
}
void main() async {
WidgetsFlutterBinding.ensureInitialized();
Workmanager().initialize(
callbackDispatcher, // The top level function, aka callbackDispatcher
isInDebugMode: false // This should be false
);
runApp(MaterialApp(home: PeriodicRequester(),));
}
var current= 8;
#override
void initState() {
// super.initState();
Workmanager().registerPeriodicTask("one", "data",frequency: const Duration(minutes: 15));
}
class PeriodicRequester extends StatelessWidget {
#override
Widget build(BuildContext context) {
return StreamBuilder<http.Response>(
stream: net.getRandomNumberFact(),
builder: (context, snapshot) {
if(snapshot.hasData)
{
var data = json.decode(snapshot.data!.body);
var l = data.length;
if(l > current){
current++;
print("updated");
AssetsAudioPlayer.newPlayer().open(
Audio("assets/song.mp3"),
);
print(current);
}
return Scaffold()```
Related
I have used connectivity_plus and internet_connection_checker packages to check the internet connectivity.
The problem occured is , the app works perfectly fine as expected when the app start's with internet on state. But when the app is opened with internet off, the dialog isn't shown !!
I assume this is happening because the build method is called before the stream of internet is listened.
Code :
class _HomePageState extends State<HomePage> {
late StreamSubscription subscription;
bool isDeviceConnected = false;
bool isAlertSet = false;
#override
void initState() {
getConnectivity();
super.initState();
}
getConnectivity() {
subscription = Connectivity().onConnectivityChanged.listen(
(ConnectivityResult result) async {
isDeviceConnected = await InternetConnectionChecker().hasConnection;
if (!isDeviceConnected && isAlertSet == false) {
showDialogBox();
setState(() {
isAlertSet = true;
});
}
},
);
}
#override
void dispose() {
subscription.cancel();
super.dispose();
}
#override
Widget build(BuildContext context) {
return Scaffold(
...
);
}
showDialogBox() => showDialog(/* no internet dialog */)
Extending the question: Is it assured that this works for all the pages ?
if yes, how ?
if not , how to overcome this?
First of all you need to listen for internet connectivity in your app first screen which is probably app.dart
GlobalKey<NavigatorState> navigatorKey = GlobalKey();
final noInternet = NoInternetDialog();
class TestApp extends StatefulWidget {
#override
State<TestApp> createState() => _TestAppState();
}
class _TestAppState extends State<TestApp> {
#override
void initState() {
super.initState();
checkInternetConnectivity();
}
#override
Widget build(BuildContext context) {
return MaterialApp(...);
}
Future<void> checkInternetConnectivity() async {
Connectivity().onConnectivityChanged.getInternetStatus().listen((event)
{
if (event == InternetConnectionStatus.disconnected) {
if (!noInternet.isShowing) {
noInternet.showNoInternet();
}
}
});
}
}
Make the screen stateful in which you are calling MaterialApp and in initState of that class check for your internet connection, like above
You are saying how can I show dialog when internet connection changes for that you have to create a Generic class or extension which you can on connectivity change. You have to pass context to that dialogue using NavigatorKey
class NoInternetDialog {
bool _isShowing = false;
NoInternetDialog();
void dismiss() {
navigatorKey.currentState?.pop();
}
bool get isShowing => _isShowing;
set setIsShowing(bool value) {
_isShowing = value;
}
Future showNoInternet() {
return showDialog(
context: navigatorKey.currentState!.overlay!.context,
barrierDismissible: true,
barrierColor: Colors.white.withOpacity(0),
builder: (ctx) {
setIsShowing = true;
return AlertDialog(
elevation: 0,
backgroundColor: Colors.transparent,
insetPadding: EdgeInsets.all(3.0.h),
content: Container(...),
);
},
);
}
}
Use checkConnectivity to check current status. Only changes are exposed to the stream.
final connectivityResult = await Connectivity().checkConnectivity();
I try to use FutureBuilder in Flutter to wait ulti my initState is finished then buil the UI for the app.
But when the app is running, the screen keep rebuilding each time I press another button (the button does totally different thing).
Future loadUser() async {
String jsonString = await storage.read(key: "jwt");
final jsonResponse = json.decode(jsonString);
loggedUser = new LoggedUser.fromJson(jsonResponse);
print(loggedUser.token);
getProfile();
getJourneyByUserId()
.then((receivedList){
addRanges(receivedList);});
}
Future<List<Journey>>getJourneyByUserId() async {
var res = await http.get(
Uri.parse("$baseUrl/journeys/userid=${loggedUser.user.userId}"),
headers: {
'Content_Type': 'application/json; charset=UTF-8',
'Authorization': 'Bearer ${loggedUser.token}',
},
);
if (res.statusCode == 200) {
print("Get journeys successfully");
}
var data = jsonDecode(res.body);
List idList = [];
for (var i in data) {
idList.add(i["journeyId"]);
}
for (var i in idList) {
var res = await http.get(
Uri.parse("$baseUrl/journeys/$i"),
);
var data = jsonDecode(res.body);
Journey userJourney = new Journey.fromJson(data);
setState(() {
journeyList.add(userJourney);
});
}
print("Journey ${journeyList.length}");
return journeyList;
}
addRanges(journeyList){
setState(() {
rangeList=[];
});
if (journeyList.isNotEmpty) {
for (var i in journeyList) {
DateTime startDate =
DateTime(i.startDate.year, i.startDate.month, i.startDate.day);
DateTime endDate =
DateTime(i.endDate.year, i.endDate.month, i.endDate.day);
setState(() {
rangeList.add(PickerDateRange(startDate, endDate));
});
}
}
print("Range ${rangeList.length}");
return rangeList;
}
returnRange() {
List<PickerDateRange> list = [];
for(int i =0; i<rangeList.length;i++){
list.add(rangeList[i]);
}
return list;
}
Future functionForBuilder() async {
return await returnRange();
}
//initState function
#override
void initState() {
super.initState();
loadUser();
functionForBuilder();
}
//build the UI
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("$_name's Profile",style: TextStyle(color: kColorPalette4),),
centerTitle: true,
),
body: Container(
child: FutureBuilder(
future: functionForBuilder(),
builder: (BuildContext context,AsyncSnapshot snapshot){
//here I set the condition for each case of snapshot
}
I have read some documents say that I should assign the functionForBuilder() to a Future variable when initState then use it in the future child of FutureBuilder. Example:
Future _future;
//initState function
#override
void initState() {
super.initState();
loadUser();
_future=functionForBuilder();
}
// then with the FutureBuilder
future: _future
With this way the screen is not rebuild anymore but my function returnRange() seems like not running as my expextation (I called the returnRange() once in the build() function).
Thanks in advance for your answer!
Whenever you assign to the _future variable again, you must do that inside a setState block, otherwise the widget will not rebuild with the new future.
For example:
void updateData() {
setState(() {
_future = functionForBuilder();
});
}
If you use FutureBuilder, it rebuild items again and again.
Try two ways:
Don't use `future: functionForBuilder(), comment it.
Remove FutureBuilder(), simply use Container().
And let me know any issue?
Code:
call your future in the initstate method not in the build as shown in the example.
class MyPage extends StatefulWidget { #override State<MyPage> createState() => _MyPageState(); } class _MyPageState extends State<MyPage> { // Declare a variable. late final Future<int> _future; #override void initState() { super.initState(); _future = _calculate(); // Assign your Future to it. } // This is your actual Future. Future<int> _calculate() => Future.delayed(Duration(seconds: 3), () => 42); #override Widget build(BuildContext context) { return Scaffold( body: FutureBuilder<int>( future: _future, // Use your variable here (not the actual Future) builder: (_, snapshot) { if (snapshot.hasData) return Text('Value = ${snapshot.data!}'); return Text('Loading...'); }, ), ); } }
I'm developing an iOS app in Flutter, using a package called audio_service.
I use AudioServiceBackground.serQueue() to set multiple MediaItem to a Queue.
In the UI part, I'm trying to use AudioService.currentMediaItemStream to display the information of the currently playing media item.
When the first song in the queue is finished, the second song will be played. However, the information on the current media item does not change.
How do I detect that the song playing in the Queue has changed?
class AudioServiceScreen extends StatefulWidget {
#override
_AudioServiceScreenState createState() => _AudioServiceScreenState();
}
class _AudioServiceScreenState extends State<AudioServiceScreen> {
#override
void initState() {
super.initState();
Future(() async {
await AudioService.connect();
await start();
});
}
#override
void dispose() {
Future(() async {
await AudioService.disconnect();
});
super.dispose();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: ///,
body: StreamBuilder<MediaItem?>(
stream: AudioService.currentMediaItemStream,
builder: (context, snapshot) {
final mediaItem = snapshot.data;
},
),
);
}
Future<dynamic> start() async {
final success = await AudioService.start(
backgroundTaskEntrypoint: _backgroundTaskEntrypoint,
);
if (success) {
await updateQueue();
}
}
Future<void> updateQueue() async {
final queue = await getMediaLibrary(); // get data from FireStore
await AudioService.updateQueue(queue);
}
}
void _backgroundTaskEntrypoint() {
AudioServiceBackground.run(() => AudioPlayerTask());
}
class AudioPlayerTask extends BackgroundAudioTask {
final AudioPlayer audioPlayer = AudioPlayer();
#override
Future<void> onStart(Map<String, dynamic>? params) async {
final session = await AudioSession.instance;
await session.configure(const AudioSessionConfiguration.speech());
await AudioServiceBackground.setState(
controls: [MediaControl.pause, MediaControl.stop],
playing: false,
processingState: AudioProcessingState.connecting,
);
}
#override
Future<void> onUpdateQueue(List<MediaItem> queue) async {
await AudioServiceBackground.setQueue(queue);
try {
await audioPlayer.setAudioSource(ConcatenatingAudioSource(
children:
queue.map((item) => AudioSource.uri(Uri.parse(item.id))).toList(),
));
} on Exception catch (e) {
await onStop();
}
}
}
Try read the docs and follow some of the example there. Because on "Background Code" section, there is "on Start" code. Maybe that code can help you out. I am sorry I cannot help you that much. I never try that package.
I'm new to Flutter, (comming from web and especially JS/VueJS)
I'm have a db in firebase that has a collection called edito and inside, i have different artist with a specific Id to call Deezer Api with it.
So what i want to do is first called my db and get the Id for each of artist and then put this id in a function as parameter to complete the url.
I did 2 Future function, one to call the db and one to call the api.
But i don't understand how to use one with the others in the build to get a listview with the information of the api of deezer for each data.
i'm getting the list but it's stuck in and endless loop.
All of my app will be on this nested function, is it possible to do this and call it in any widget that i want ?
here is my code, thanks
import 'package:flutter/material.dart';
import 'package:cloud_firestore/cloud_firestore.dart';
import 'package:http/http.dart' as http;
import 'dart:convert';
class GetAlbum extends StatefulWidget {
#override
_GetAlbumState createState() => _GetAlbumState();
}
class _GetAlbumState extends State<GetAlbum> {
Map mapResponse;
Future<QuerySnapshot> getDocument() async{
return FirebaseFirestore.instance.collection("edito").get();
}
Future<dynamic> fetchData(id) async{
http.Response response;
response = await http.get('https://api.deezer.com/album/' + id);
if(response.statusCode == 200){
setState(() {
mapResponse = json.decode(response.body);
});
}
}
Future<dynamic> getDocut;
Future<dynamic> getArtist;
#override
void initState() {
getDocut = getDocument();
getArtist = fetchData(null);
super.initState();
}
#override
Widget build(BuildContext context) {
return FutureBuilder<QuerySnapshot>(
future : getDocut,
builder: (BuildContext context, AsyncSnapshot<QuerySnapshot> snapshot){
if(!snapshot.hasData) {
return CircularProgressIndicator();
}else{
return new ListView(
children: snapshot.data.docs.map<Widget>((document){
print(document.data().length);
return FutureBuilder(
future: fetchData(document.data()['idDeezer'].toString()),
builder: (context, snapshot){
return Container(
child: mapResponse==null?Container(): Text(mapResponse['title'].toString(), style: TextStyle(fontSize: 30),),
);
}
);
}).toList(),
);
}
},
);
}
}
Here's a simplified example of making two linked Future calls where the 2nd depends on data from the first, and using the results in a FutureBuilder:
import 'package:flutter/material.dart';
class FutureBuilder2StatefulPage extends StatefulWidget {
#override
_FutureBuilder2StatefulPageState createState() => _FutureBuilder2StatefulPageState();
}
class _FutureBuilder2StatefulPageState extends State<FutureBuilder2StatefulPage> {
Future<String> _slowData;
#override
void initState() {
super.initState();
_slowData = getAllSlowData(); // combined async calls into one future
}
// linked async calls
Future<String> getAllSlowData() async {
int id = await loadId(); // make 1st async call for id
return loadMoreData(id: id); // use id in 2nd async call
}
Future<int> loadId() async {
int _id = await Future.delayed(Duration(seconds: 2), () => 42);
print('loadId() completed with: $_id'); // debugging
return _id;
}
Future<String> loadMoreData({int id}) async {
return await Future.delayed(Duration(seconds: 2), () => 'Retrieved data for id:$id');
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text('FutureBldr Stateful'),
),
body: FutureBuilder<String>(
future: _slowData,
builder: (context, snapshot) {
if (snapshot.hasData) {
return Center(child: Text(snapshot.data));
}
return Center(child: Text('Loading...'));
},
),
);
}
}
This avoids having to nest the FutureBuilder which may be error prone.
And calling future methods directly from a FutureBuilder is not recommended since the call could be made many times if its containing widget is rebuilt (which can happen a lot).
I tried to add firebase in the first one but i get null for the id in the get AllSlowDAta but i got it right with the Future.delayed.
// linked async calls
Future<String> getAllSlowData() async {
String id = await loadId(); // make 1st async call for id
return loadMoreData(id: id); // use id in 2nd async call
}
Future<dynamic> loadId() async {
//return await Future.delayed(Duration(seconds: 2), () => '302127');
await FirebaseFirestore.instance.collection("edito")
.get()
.then((QuerySnapshot querySnapshot) {
querySnapshot.docs.forEach((doc) {
return doc.data()["idDeezer"];
});
});
}
Future<dynamic> loadMoreData({String id}) async {
http.Response response;
response = await http.get('https://api.deezer.com/album/' + id);
if(response.statusCode == 200){
setState(() {
return json.decode(response.body);
});
}
}
My function defination is below
Future<List<Item>> fetchGitUsers() async {
final response = await http.get('https://');
if (response.statusCode == 200) {
GitUsers gitUser = GitUsers.fromJson(json.decode(response.body));
return gitUser.items;
}
} / Function end
class GitUsers {
List<Item> items;
}
class ... extends State<SearchController> {
#override
void initState() {
super.initState();
gitUsers = fetchGitUsers() as List<Item>;
}
}
But I am getting below error on emulator screen..
in type cast.
You didn't add await
Try this
void getUsers() async{
gitUsers = await fetchGitUsers();
}
#override
void initState() {
super.initState();
getUsers();
}
}
If you want to use the git users in a UI (e.g ListView), consider using FutureBuilder.
Like this
FutureBuilder(
future: fetchGitUsers(),
builder: (context, snapshot){
if(!snapshot.hasData) return CircularProgressIndicator();
return ListView();
}
)