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Methods are not getting executed in the written order inside onPressed

Im trying to create a flutter app with a simple raised button that does the following:
sends an sms in the background using the sms package opens a webpage
2. in the app(only for 5 seconds) using url_launcher opens the phones
3. native app for making a voice call with the onPressed property.
And I wanted it to be in this order so that I can make the phone call at the end. However, the inside the onPressed opens the native phone call app first, which doesnt let my web page open unless I exit out of the phone call app.
Im having a hard time understanding why the phone call native app is opened first, even though I make the call the _makePhoneCall() method only after I make the _launchInApp(toLaunch) call. sendSMS() is being called correctly
How can I set this in a way that the phone call native app is called only after the webpage is opened in the app and follows the order? Any help would be great
Below is the piece of code:
import 'package:flutter/material.dart';
import 'package:url_launcher/url_launcher.dart';
import 'package:sms/sms.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Packages testing',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Packages testing'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
String _phone = '';
_launchInApp(String url) async {
if (await canLaunch(url)) {
await launch(
url,
forceSafariVC: true,
forceWebView: true,
headers: <String, String>{'my_header_key': 'my_header_value'},
);
} else {
throw 'Could not launch $url';
}
}
_makePhoneCall(String url) async {
if (await canLaunch(url)) {
await launch(url);
} else {
throw 'Could not launch $url';
}
}
void sendSMS() {
SmsSender sender = new SmsSender();
sender.sendSms(new SmsMessage(_phone, 'Testing Handset'));
}
#override
Widget build(BuildContext context) {
const String toLaunch = 'https://flutter.dev/';
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: ListView(
children: <Widget>[
Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Padding(
padding: const EdgeInsets.all(16.0),
child: TextField(
onChanged: (String text) => _phone = text,
decoration:
const InputDecoration(hintText: 'Phone Number')),
),
FlatButton(
onPressed: () => setState(() {
sendSMS();
_launchInApp(toLaunch);
_makePhoneCall('tel:$_phone');
}),
child: const Text('Run All'),
),
const Padding(padding: EdgeInsets.all(16.0)),
],
),
],
),
);
}
}

You will have to use the await keyword before the _launchInApp function to make it work properly. Try the following code.
FlatButton(
onPressed: () aync {
sendSMS();
await _launchInApp(toLaunch);
_makePhoneCall('tel:$_phone');
}),
child: const Text('Run All'),
),

You created async functions but when you called them you did not specify that you want to wait for them to complete. Add the await keyword in OnPressed

Open Flutter Application Using Dynamic Links [closed]

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I'm building a flutter application, and am having some trouble actually opening the app using the firebase_dynamic_links package. I basically took the example code found at https://pub.dev/packages/firebase_dynamic_links#-example-tab- in order to get started, but changed the information in their example to match my own firebase project (which has been setup in both android and iOS, but this testing has all been done with iOS).
I will include code and more useful information below, but I was really just hoping to get a simplified example of how this process should work. I have searched online quite a bit, following different tutorials, but none of them have done the trick for me. It could just be that I'm quite new to flutter, and am missing basic things. In my final application, I will be using dynamic links to allow users to invite other users to join the app (as well as groups within the app) via text, just to give context as to why it is needed.
Here is the code for what I have so far, but as I mentioned it is largely based off of the example from the link above.
main.dart
// Copyright 2019 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
import 'dart:async';
import 'dart:io' show Platform;
import 'package:flutter/material.dart';
import 'package:firebase_dynamic_links/firebase_dynamic_links.dart';
import 'package:flutter/services.dart';
import 'package:url_launcher/url_launcher.dart';
import 'package:firebase_core/firebase_core.dart';
import 'package:shopsync/helloworld.dart';
void main() async {
//Setup firebase connection
WidgetsFlutterBinding.ensureInitialized();
final FirebaseApp app = await FirebaseApp.configure(
name: 'shop-sync-d97d8',
options: Platform.isIOS
? const FirebaseOptions(
googleAppID: 'my_googleAppID',
gcmSenderID: 'my_senderID',
databaseURL: 'https://shop-sync-d97d8.firebaseio.com',
apiKey: 'AIzaSyC1TdwTs_KRXMGG2oIAGMX8v48HWqS62dc',
)
: const FirebaseOptions(
googleAppID: 'my_googleAppID',
apiKey: 'myApiKey',
databaseURL: 'my_url',
),
);
runApp(MaterialApp(
title: 'Dynamic Links Example',
routes: <String, WidgetBuilder>{
'/': (BuildContext context) => _MainScreen(),
'/helloworld': (BuildContext context) => HelloWorldScreen(),
},
));
}
class _MainScreen extends StatefulWidget {
#override
State<StatefulWidget> createState() => _MainScreenState();
}
class _MainScreenState extends State<_MainScreen> {
String _linkMessage;
bool _isCreatingLink = false;
String _testString =
"To test: long press link and then copy and click from a non-browser "
"app. Make sure this isn't being tested on iOS simulator and iOS xcode "
"is properly setup. Look at firebase_dynamic_links/README.md for more "
"details.";
#override
void initState() {
super.initState();
initDynamicLinks();
}
void initDynamicLinks() async {
final PendingDynamicLinkData data =
await FirebaseDynamicLinks.instance.getInitialLink();
final Uri deepLink = data?.link;
if (deepLink != null) {
Navigator.pushNamed(context, deepLink.path);
}
FirebaseDynamicLinks.instance.onLink(
onSuccess: (PendingDynamicLinkData dynamicLink) async {
final Uri deepLink = dynamicLink?.link;
if (deepLink != null) {
Navigator.pushNamed(context, deepLink.path);
}
}, onError: (OnLinkErrorException e) async {
print('onLinkError');
print(e.message);
});
}
Future<void> _createDynamicLink(bool short) async {
setState(() {
_isCreatingLink = true;
});
final DynamicLinkParameters parameters = DynamicLinkParameters(
uriPrefix: "https://shopsync.page.link",
link: Uri.parse("https://shopsync.page.link/helloworld"),
androidParameters: AndroidParameters(
packageName: 'com.chrismcdonnell.shopsync',
minimumVersion: 0,
),
dynamicLinkParametersOptions: DynamicLinkParametersOptions(
shortDynamicLinkPathLength: ShortDynamicLinkPathLength.short,
),
iosParameters: IosParameters(
bundleId: 'com.chrismcdonnell.shopsync',
minimumVersion: '0',
),
);
Uri url;
if (short) {
final ShortDynamicLink shortLink = await parameters.buildShortLink();
url = shortLink.shortUrl;
} else {
url = await parameters.buildUrl();
}
setState(() {
_linkMessage = url.toString();
_isCreatingLink = false;
});
}
#override
Widget build(BuildContext context) {
return Material(
child: Scaffold(
appBar: AppBar(
title: const Text('Dynamic Links Example'),
),
body: Builder(builder: (BuildContext context) {
return Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
ButtonBar(
alignment: MainAxisAlignment.center,
children: <Widget>[
RaisedButton(
onPressed: !_isCreatingLink
? () => _createDynamicLink(false)
: null,
child: const Text('Get Long Link'),
),
RaisedButton(
onPressed: !_isCreatingLink
? () => _createDynamicLink(true)
: null,
child: const Text('Get Short Link'),
),
],
),
InkWell(
child: Text(
_linkMessage ?? '',
style: const TextStyle(color: Colors.blue),
),
onTap: () async {
if (_linkMessage != null) {
await launch(_linkMessage);
}
},
onLongPress: () {
Clipboard.setData(ClipboardData(text: _linkMessage));
Scaffold.of(context).showSnackBar(
const SnackBar(content: Text('Copied Link!')),
);
},
),
Text(_linkMessage == null ? '' : _testString)
],
),
);
}),
),
);
}
}
class _DynamicLinkScreen extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Material(
child: Scaffold(
appBar: AppBar(
title: const Text('Hello World DeepLink'),
),
body: const Center(
child: Text('Hello, World!'),
),
),
);
}
}
helloworld.dart
//IMPORT NEEDED PACKAGES
import 'package:flutter/material.dart';
import 'package:flutter/cupertino.dart';
//CREATE STATEFUL WIDGET
class HelloWorldScreen extends StatefulWidget {
#override
_HelloWorldScreen createState() => _HelloWorldScreen();
}
//CREATE STATE WIDGET
class _HelloWorldScreen extends State<HelloWorldScreen> {
#override
Widget build(BuildContext context) {
//Since this class represents an entire screen, return a scaffold with elements inside it
return Scaffold(
backgroundColor: Colors.white,
//Create AppBar w/ title "My Account"
appBar: AppBar(
title: Text('Hello World'),
automaticallyImplyLeading: false,
),
//Most of the content of the screen will go here
body: SafeArea(
child: Text('Testing'),
),
);
}
}
And lastly, here is the dynamic link I created within the console for testing. Although the final version of the application will create them programatically.
If anything else is needed please let me know. Any help would be greatly appreciated.

Add progress bar in flutter when open pdf file from url

I have a problem and I cannot solve it and I did not find a source to solve it on Google, I have a page where I view a PDF file through a link, and I have a CircularProgressIndicator and I want to replace it with a progress bar showing the percentage of downloading the file, can I do that?
I have attached my code
import 'package:flutter/material.dart';
import 'package:flutter_plugin_pdf_viewer/flutter_plugin_pdf_viewer.dart';
class ReadPdf extends StatefulWidget {
final String value;
ReadPdf({Key key, this.value}) : super(key: key);
#override
_ReadPdfState createState() => _ReadPdfState();
}
class _ReadPdfState extends State<ReadPdf>{
bool _isloading = false, _isInit = true;
PDFDocument document;
#override
void initState() {
super.initState();
}
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
backgroundColor: Color.fromRGBO(58, 66, 86, 1.0),
body: Container(
child: Column(
children: <Widget>[
Expanded(child:Center(
child: _isInit? MaterialButton(child: Text('Go'), onPressed: () {_loadFromURL(widget.value);},
color: Color.fromRGBO(64, 75, 96, .9),
textColor: Colors.white,
) : _isloading? Center(child: CircularProgressIndicator(),) : PDFViewer(document: document,indicatorBackground: Colors.deepPurple,),
),),
Row(
mainAxisSize: MainAxisSize.max,
children: <Widget>[
],
),
],
),
),
),
);
}
_loadFromURL(String url) async{
setState(() {
_isInit = false;
_isloading = true;
});
document = await PDFDocument.fromURL('${url}'); setState(() {
_isloading = false;
});
}
}

I have an app with the same feature, I used Dio this package supports downloading a file to your phone.
All you need to do is
Dio dio = Dio();
dio.download("*YOUR URL WHERE YOU WANT TO DOWNLOAD A FILE*",
"*YOUR DESTINATION PATH*", onReceiveProgress: (rec, total) {
print("Downloading " + ((rec / total) * 100).toStringAsFixed(0) + "%");
});

Never used this for pdf, but I've tried it for NetworkImage().
Not sure if it'll help. But you can just try it if there's a way to use loadingBuilder in your code.
Image.network(
imageUrl,
fit: BoxFit.cover,
loadingBuilder: (BuildContext context, Widget child,
ImageChunkEvent loadingProgress) {
if (loadingProgress == null)
return child;
else {
return Center(
child: CircularProgressIndicator(
value: loadingProgress.expectedTotalBytes != null
? loadingProgress.cumulativeBytesLoaded /
loadingProgress.expectedTotalBytes
: null,
),
);
}
},
);

u can use flutter_cached_pdfview
and this an example to view a pdf from URL and cache it with placeholder
u can replace placeholder with any widget like CircularProgressIndicator
PDF().cachedFromUrl(
'http://africau.edu/images/default/sample.pdf',
placeholder: (progress) => Center(child: Text('$progress %'))
)
take a look https://pub.dev/packages/flutter_cached_pdfview

Not able to view web page in webview on Android emulator

I am trying to run the WebView Sample of Flutter in android emulator which is provided by Android studio itself. Now the problem I am facing is while I am running the sample I am not able to view the web page in WebView itself.
When the app runs for the first time it asks me to open the initialUrl into either into the chrome or web browser see below screenshots.
However, when I run the same sample in my mobile device it works fine and I can see the web page insdie WebView
Code
class _WikipediaExplorerState extends State<WikipediaExplorer> {
Completer<WebViewController> _controller = Completer<WebViewController>();
final Set<String> _favorites = Set<String>();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Wikipedia Explorer'),
// This drop down menu demonstrates that Flutter widgets can be shown over the web view.
actions: <Widget>[
NavigationControls(_controller.future),
Menu(_controller.future, () => _favorites),
],
),
body: WebView(
initialUrl: 'https://en.wikipedia.org/wiki/Kraken',
onWebViewCreated: (WebViewController webViewController) {
_controller.complete(webViewController);
},
),
floatingActionButton: _bookmarkButton(),
);
}
_bookmarkButton() {
return FutureBuilder<WebViewController>(
future: _controller.future,
builder:
(BuildContext context, AsyncSnapshot<WebViewController> controller) {
if (controller.hasData) {
return FloatingActionButton(
onPressed: () async {
var url = await controller.data.currentUrl();
_favorites.add(url);
Scaffold.of(context).showSnackBar(
SnackBar(content: Text('Saved $url for later reading.')),
);
},
child: Icon(Icons.favorite),
);
}
return Container();
},
);
}
}

Manage state of one page from another class

I'm building an app for training in Flutter and I'm actually stuck in the filter functionality.
I have a ListView where I fetch data from TheMovieDB API and a ModalBottomSheet with three FilterChips for selecting the filter criteria (popular, top rated and latest movies).
And here's where I'm stuck. I want to call the "_loadNextPage()" method when the user presses the "Done" button in the ModalBottomSheet through "performUpdate()" but I can't do it because they're not in the same class.
I'll post the code down below for better understanding.
class _HomePageState extends State<HomePage> {
RequestProvider _requestProvider = new RequestProvider();
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("FluttieDB"),
actions: <Widget>[
IconButton(
icon: Icon(Icons.filter_list),
onPressed: () => buildFilterBottomSheet(),
)
],
),
body: MovieList(_requestProvider, _currentFilter),
);
}
void buildFilterBottomSheet() {
showModalBottomSheet(
context: context,
builder: (builder) {
return Container(
height: 150.0,
decoration: BoxDecoration(color: Colors.white),
child: Column(
children: <Widget>[
buildFilterTitle(context),
Expanded(
child: _FilterChipRow(),
),
],
),
);
});
}
Widget buildFilterTitle(BuildContext context) {
return Container(
padding: const EdgeInsets.symmetric(horizontal: 12.0, vertical: 6.0),
alignment: Alignment.centerLeft,
height: 46.0,
decoration: BoxDecoration(color: Colors.blue),
child: Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
mainAxisSize: MainAxisSize.max,
children: <Widget>[
Text(
"Filter by",
style: TextStyle(color: Colors.white, fontSize: 20.0),
),
OutlineButton(
onPressed: () => performUpdate(context),
padding: const EdgeInsets.all(0.0),
shape: const StadiumBorder(),
child: Text(
"Done",
style: TextStyle(color: Colors.white),
),
),
],
),
);
}
void performUpdate(BuildContext context) {
MovieList _movieList = new MovieList(_requestProvider, _currentFilter);
_movieList.createState()._loadNextPage();
Navigator.pop(context);
}
}
class MovieList extends StatefulWidget {
MovieList(this.provider, this.currentFilter, {Key key}) : super(key: key);
final RequestProvider provider;
final String currentFilter;
#override
_MovieListState createState() => new _MovieListState();
}
class _MovieListState extends State<MovieList> {
List<Movie> _movies = List();
int _pageNumber = 1;
LoadingState _loadingState = LoadingState.LOADING;
bool _isLoading = false;
_loadNextPage() async {
_isLoading = true;
try {
var nextMovies = await widget.provider
.provideMedia(widget.currentFilter, page: _pageNumber);
setState(() {
_loadingState = LoadingState.DONE;
_movies.addAll(nextMovies);
_isLoading = false;
_pageNumber++;
});
} catch (e) {
_isLoading = false;
if (_loadingState == LoadingState.LOADING) {
setState(() => _loadingState = LoadingState.ERROR);
}
}
}
#override
void initState() {
super.initState();
_loadNextPage();
}
#override
Widget build(BuildContext context) {
switch (_loadingState) {
case LoadingState.DONE:
return ListView.builder(
itemCount: _movies.length,
itemBuilder: (BuildContext context, int index) {
if (!_isLoading && index > (_movies.length * 0.7)) {
_loadNextPage();
}
return MovieListItem(_movies[index]);
});
case LoadingState.ERROR:
return Center(
child: Text("Error retrieving movies, check your connection"));
case LoadingState.LOADING:
return Center(child: CircularProgressIndicator());
default:
return Container();
}
}
}
As you can see, I did some experiments in the performUpdate() but it doesn't refresh the ListView with the selected option in the filters and I don't think it's the best way to achieve what I want.
Thanks and sorry if the question is a bit dumb. I'm a little bit newbie in Flutter.

Redux is a great state management library that originated with React and JS, but has been ported to Dart, and has a flutter specific library as well. Redux is a very powerful framework which uses a pub/sub system to allow your view to subscribe to changes to the model, while using a system of "actions" and "reducers" to update the model.
A great tutorial for getting up and running with Redux in Flutter can be found here
Alternatively you could look into the scoped model, which is another state management library for flutter. The scoped model is less capable, but for simple use cases may be more than adequate.
Further reading:
Understand and choose a state management solution
You Might Not Need Redux