Does anybody know why the Geolocation.getCurrentPosition() from dart:html doesn't work when running in release mode with sound null safety enabled (flutter run --release -d chrome)?
When making this call I do get an instance of Geoposition back but when I try to access one of it's members I get the following error message:
Uncaught TypeError: n.grq is not a function
at main.dart:39
at WD.a (async_patch.dart:316)
at WD.$2 (async_patch.dart:341)
at VR.$1 (async_patch.dart:292)
at UG.SB (zone.dart:1612)
at UG.ug (zone.dart:1611)
at Tf.$0 (future_impl.dart:118)
at Object.n3 (future_impl.dart:733)
at Y.ib (future_impl.dart:539)
at T7.$0 (future_impl.dart:577)
If I run the same code in debug (flutter run -d chrome or without NNBD flutter run -d chrome --release --no-sound-null-safety everything works fine). A simple App that reproduces this behaviour looks like this (it's a slightly changed version of the default Flutter counter template):
import 'dart:html' as html;
import 'package:flutter/foundation.dart';
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
// This widget is the root of your application.
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
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 _position = "Unknown";
Future<void> _currentPosition() async {
final geolocation = html.window.navigator.geolocation;
final position = await geolocation.getCurrentPosition();
final latitude = position.coords?.latitude ?? 'n/a';
final longitude = position.coords?.longitude ?? 'n/a';
setState(() {
_position =
'Latitude: $latitude, Longitude: $longitude';
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title!),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'Your current position is:',
),
Text(
'$_position',
style: Theme.of(context).textTheme.headline4,
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: _currentPosition,
tooltip: 'Current position',
child: Icon(Icons.location_on),
),
);
}
}
This turns out to be a bug in Dart. I have created a bug report which can be tracked here: https://github.com/dart-lang/sdk/issues/45562
Related
I am coding a PDF on flutter using 'syncfusion_flutter_pdfviewer' library. I tried everything but always I receive the same error message:
Next code I'm trying
import 'package:flutter/material.dart';
import 'package:syncfusion_flutter_pdfviewer/pdfviewer.dart';
void main() {
runApp(MaterialApp(
title: 'Syncfusion PDF Viewer Demo',
home: HomePage(),
));
}
/// Represents Homepage for Navigation
class HomePage extends StatefulWidget {
#override
_HomePage createState() => _HomePage();
}
class _HomePage extends State<HomePage> {
final GlobalKey<SfPdfViewerState> _pdfViewerKey = GlobalKey();
#override
void initState() {
super.initState();
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: const Text('Syncfusion Flutter PDF Viewer'),
actions: <Widget>[
IconButton(
icon: const Icon(
Icons.bookmark,
color: Colors.white,
semanticLabel: 'Bookmark',
),
onPressed: () {
_pdfViewerKey.currentState?.openBookmarkView();
},
),
],
),
body: SfPdfViewer.network(
'https://cdn.syncfusion.com/content/PDFViewer/flutter-succinctly.pdf',
key: _pdfViewerKey,
),
);
}
}
Had a similar problem and it turned out to be a mismatch between plugin version and flutter version. (I went back and forth to a new Flutter version).
Wrote a more detailed answer here: Flutter completely broken after update (again)
Also - the syncfusion support proved very useful for this
I'm currently working on a Flutter project. I have been given Icons by the designer.
One of the Icons looks like this
Now I'd like to fill the inside of the Icon with color so that it looks like this
How can I achieve this in flutter? I really tried a lot. Like using ClipRect and other Classes. But none gave the desired results.
Try this one.
import 'package:flutter/material.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
bool _isBluetoothOn = false;
class _MyHomePageState extends State<MyHomePage> {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
IconButton(
onPressed: () async {
print(_isBluetoothOn);
setState(() {
_isBluetoothOn = !_isBluetoothOn;
});
print(_isBluetoothOn);
},
icon: Icon(
_isBluetoothOn ? Icons.favorite : Icons.favorite_border,
color: Colors.greenAccent,
size: 40,
),
),
],
),
),
);
}
}
You can simply ask designer for filled icons too and show them when they are clicked.
So it goes like this:
if button clicked:
show filledIcon
else:
show unfilledIcon
You can code that in Flutter like:
icon:clicked? Icon(filledIcon):Icon(unfilledIcon)
This is the easiest way to do this.
I have an example that implements an example of Android Alarm Manager with flutter, the event is called normal, however, I want that when the alarm goes off, a native code (Java or Kt) is executed.
Example:
As soon as the alarm goes off even in the background or locked screen, the app will execute my code in Java.
In native Java we created a class that inherits from BroadcastReceiver and implements the onReceive method, in Android Native I would open my app even in the background with native code.
How can I get the flutter to call my native code to run when the alarm is triggered?
My code example:
import 'package:flutter/material.dart';
import 'package:android_alarm_manager/android_alarm_manager.dart';
import 'package:android_intent/android_intent.dart';
import 'package:android_intent/flag.dart';
import 'package:platform/platform.dart';
void main() async {
WidgetsFlutterBinding.ensureInitialized();
await AndroidAlarmManager.initialize();
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Alarme app',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Alarme'),
debugShowCheckedModeBanner: false,
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key? key, required this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
void _openLinkInGoogleChrome() {
print('entered');
if (const LocalPlatform().isAndroid) {
// **run Native code java here that implemented onReceive on class .java or .kt !!!**
}
}
class _MyHomePageState extends State<MyHomePage> {
void adicionarAlarme(BuildContext context) async {
await AndroidAlarmManager.periodic(
const Duration(seconds: 3), 0, _openLinkInGoogleChrome);
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'Clique no botão abaixo para adicionar um alarme',
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: () => adicionarAlarme(context),
tooltip: 'Adicionar alarme',
child: Icon(Icons.add),
), // This trailing comma makes auto-formatting nicer for build methods.
);
}
}
I need to open and save simple text files that may be on the device. For example in Documents, Downloads, etc. Wherever files are available for other programs, in android terminology it is "External Storage"
path_provider provides several methods. One of them getExternalStorageDirectory(). The android documentation says:
This method was deprecated in API level 29. To improve user privacy,
direct access to shared/external storage devices is deprecated. When
an app targets Build.VERSION_CODES.Q link
If I use methods path_provider
getExternalStorageDirectory() → /storage/emulated/0/Android/data/myapp.name/files
getApplicationDocumentsDirectory() → /data/user/0/myapp.name/app_flutter
getExternalStorageDirectories(type: StorageDirectory.documents) return List which contains
/storage/emulated/0/Android/data/myapp.name/files/Documents
/storage/1CEE-4019/Android/data/myapp.name/files/Documents
On my android emulator (Api 30) real external documents are located at
/storage/emulated/0/Documents
/storage/emulated/0/Download
How can I access them? As I understand it, there are no alternatives forpath_provider
you va use external_path package
You can copy paste run full code below
You can use package https://pub.dev/packages/ext_storage
code snippet
String pathDownload = await ExtStorage.getExternalStoragePublicDirectory(
ExtStorage.DIRECTORY_DOWNLOADS);
print(pathDownload);
String pathDoc = await ExtStorage.getExternalStoragePublicDirectory(
ExtStorage.DIRECTORY_DOCUMENTS);
print(pathDoc);
output
I/flutter ( 7361): /storage/emulated/0/Download
I/flutter ( 7361): /storage/emulated/0/Documents
full code
import 'package:flutter/material.dart';
import 'package:ext_storage/ext_storage.dart';
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
void _incrementCounter() async {
String pathDownload = await ExtStorage.getExternalStoragePublicDirectory(
ExtStorage.DIRECTORY_DOWNLOADS);
print(pathDownload);
String pathDoc = await ExtStorage.getExternalStoragePublicDirectory(
ExtStorage.DIRECTORY_DOCUMENTS);
print(pathDoc);
setState(() {
_counter++;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'You have pushed the button this many times:',
),
Text(
'$_counter',
style: Theme.of(context).textTheme.headline4,
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: _incrementCounter,
tooltip: 'Increment',
child: Icon(Icons.add),
),
);
}
}
I'm pretty new on Flutter and I trying to build a desktop app.
I did all steps of following guide: https://medium.com/flutter-community/flutter-from-mobile-to-desktop-93635e8de64e (Running your own project (compiling the Go desktop project))
Unfornatelly, when I try to run the code I have this error:
NoSuchMethodError: Class "Window" has no instance getter 'locales'
Receiver: Instance of Window
Tried calling: locales
Thank you in advance
The Operating System is Windows 8.1 and following the code. It is the starter one where I just added the debugDefaultTargetPlatformOverride part.
import 'package:flutter/material.dart';
import 'package:flutter/foundation.dart' show
debugDefaultTargetPlatformOverride;
void main(){
debugDefaultTargetPlatformOverride = TargetPlatform.fuchsia;
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
),
home: MyHomePage(title: 'Flutter Demo Home Page'),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
void _incrementCounter() {
setState(() {
_counter++;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'You have pushed the button this many times:',
),
Text(
'$_counter',
style: Theme.of(context).textTheme.display1,
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: _incrementCounter,
tooltip: 'Increment',
child: Icon(Icons.add),
),
methods.
);
}
}