On Safari for some of my onTap functions, my code is being executed twice. It doesn't always happen just from times to times.
for example:
goToSearchPage() {
Navigator.pushNamed(
context, '/searchPage',
arguments: SearchPageArguments(
matchcode: _controllerSearchInput.text.trim().toString()
)
);
_controllerSearchInput.text = '';
}
onTap: () {
_controllerSearchInput.text = matchcode;
goToSearchPage();
},
When onTap sometimes it loads 2 times searchpage, first time with a correct argument and second time with an empty argument.
An other example:
onTap: () {
setState(() {
_loading = true;
});
http.Client()
.get("https://myApi")
.then((response) =>response.body)
.then(json.decode)
.then((json) {
setState(() {
_loading = false;
});
Navigator.popAndPushNamed(
context, '/paymentPage',
arguments: PaymentPageArguments(
ordersToPay: json
)
);
});
}
In this case after my API is being called paymentPage is not showing because I think navigator is being pop twice instead of one time. My API is only being call one time though.
Those weird behaviors only happens in safari, I'm not sure how i could debug it.
Related
I have got a State Management Problem I couldn't get rid of and I want to reach out to you.
Basically, I activate with the Buttons a game and I am sending a String to the uC. The uC does its stuff and sends a response to Flutter including gameFinished=true (that works).
Now I want to reset the State of the Button to the init state WITHOUT pressing the Button. Following are some things I tried that didn't work.
#override
void initState() {
super.initState();
setState(() {
gameAktivated = false;
gameStarted = false;
});
}
void asyncSetState() async {
setState(() async {
gameAktivated = false;
gameStarted = false;
});
}
I am changing the style from "Start" to "Stop" when the Button is pressed and I send Data to the uC. (Works)
Edit: Ofc I have a second button that triggers gameAktivated=true :)
ElevatedButton(
onPressed: () {
if (gameAktivated) {
setState(() {
gameStarted = !gameStarted;
});
if (gameStarted) {
//Send Data to uC
} else if (!gameStarted) {
//Send Data to uC
}
}
},
child:
!gameStarted ? const Text('Start') : const Text('Stop'),
),
Button Displays Stop now.
Following I am receiving a String from the uC that I jsonEncode and I receive gameFinished=true. (Works)
Container(
child: streamInit
? StreamBuilder<List<int>>(
stream: stream,
builder: (BuildContext context,
AsyncSnapshot<List<int>> snapshot) {
if (snapshot.hasError) {
return Text('Error: ${snapshot.error}');
}
if (snapshot.connectionState ==ConnectionState.active) {
// getting data from Bluetooth
var currentValue =const BluetoothConnection().dataParser(snapshot.data);
config.jsonDeserializeGameFinished(currentValue);
if(config.gameFinished){
setState(() {
gameAktivated = false;
gameStarted = false;
});
asyncSetState();//Tested both methods seperate!
}
return Column(
children: [
Text(config.time.toString()),
],
);
} else {
return const Text(
'Check the stream',
textAlign: TextAlign.center,
);
}
},
): const Text("NaN",textAlign: TextAlign.center,),
),
When I try to reset the state like in the code above this error occures:
Calling setState Async didnt work for me either.
Where and how can I set the state based on the response from the uC?
Is it possible without using Provider Lib?
Thanks in advance Manuel.
Actually this error is not about the changing the state of button. Its a common mistake to update the widget state when its still building the widget tree.
Inside your StreamBuilder, you are trying to update the state before creating the UI which is raising this issue.
if(config.gameFinished){
setState(() {
gameAktivated = false;
gameStarted = false;
});
This will interrupt the build process of StreamBuilder as it will start updating the whole page. You need to move it out of the StreamBuilder's builder method.
To do that simply convert your stream to a broadcast, which will allow you to listen your stream multiple time.
var controller = StreamController<String>.broadcast();
Then inside the initState of the page you can setup a listener method to listen the changes like this
stream.listen((val) => setState((){
number = val;
}));
Here you can change the state values because from here it will not interrupt the widget tree building cycle.
For more details see this example I created
https://dartpad.dev/?id=a7986c44180ef0cb6555405ec25b482d
If you want to call setState() immediately after the build method was called you should use:
WidgetsBinding.instance.addPostFrameCallback((timeStamp) {
// this method gets called once directly after the previous setState() finishes.
});
Answer to my own Question:
In initState()
added this:
stream.listen((event) {
String valueJSON = const BluetoothConnection().dataParser(event);
config.jsonDeserializeGameFinished(valueJSON);
if (config.gameFinished) {
setState(() {
gameAktivated = false;
gameStarted = false;
});
}
});
The Code above listens to the stream, UTF-8 Decodes and JSON-Decodes the data. After this you can access the variable to set a state.
I have a widget with this method in flutter that is called by two different screens, I would like 'Navigator.pop' to change its behavior depending on which screen calls it.
On the first screen it would apply a common 'pop', and on the second screen, for a specific route. Can you help me with this?
`
void salvarCartao(InputCartaoDto cartao, BuildContext context) async {
var cartaoDto = await AdicionarCartaoCommand().execute(cartao, context);
if (cartaoDto != null) {
var usuarioCorrente = await ObterUsuarioCorrenteCommand().execute();
var listaCartoes = usuarioCorrente?.cartoes;
listaCartoes?.add(cartaoDto);
AtualizarUsuarioCommand().execute(usuarioCorrente!);
}
//if screen 1 called the method:
Navigator.pop(context);
//if screen 2:
Navigator.popUntil(context, ModalRoute.withName('/carrinho-pagamento'));
}
`
I'm actually still learning flutter, I couldn't think of a solution with my current knowledge
then redefine your function. Ex:
void salvarCartao(InputCartaoDto cartao, BuildContext context, int opt) async {
var cartaoDto = await AdicionarCartaoCommand().execute(cartao, context);
if (cartaoDto != null) {
var usuarioCorrente = await ObterUsuarioCorrenteCommand().execute();
var listaCartoes = usuarioCorrente?.cartoes;
listaCartoes?.add(cartaoDto);
AtualizarUsuarioCommand().execute(usuarioCorrente!);
}
//if screen 1 called the method:
if(opt ==1)
Navigator.pop(context);
else
//if screen 2:
Navigator.popUntil(context, ModalRoute.withName('/carrinho-pagamento'));
}
You can pass a flag to the salvarCartao function, depending on which screen calls it.
isFromScreen2 ? Navigator.popUntil(context, ModalRoute.withName('/carrinho-pagamento')) : Navigator.pop(context);
or
if (isFromScreen2) {
Navigator.popUntil(context, ModalRoute.withName('/carrinho-pagamento'))
} else {
Navigator.pop(context);
}
I'm developing a qr scan app. And using qr_code_scanner 0.5.2.
When i scan a qr code, my app jump to another page with the scanned code, but the app still scanning the qr codes and new pages appears until you d not focus on any qr code.
How can i scan codes one by one and pause scanning while on the another page and resume scanning when the new page is closed?
Thanks
code:
void _onQRViewCreated(QRViewController controller) {
setState(() {
this.controller = controller;
});
controller.scannedDataStream.listen((scanData) {
setState(() {
controller.pauseCamera();
Navigator.push(context,
MaterialPageRoute(builder: (context) {
return ReadData(data: scanData.code);
}),
);
controller.resumeCamera();
});
});
}
edit:
solution code:
void _onQRViewCreated(QRViewController controller) {
this.controller = controller;
controller.scannedDataStream.listen((scanData) async {
controller.pauseCamera();
await Navigator.push(
context,
MaterialPageRoute(builder: (context) {
return ReadData(data: scanData.code);
}),
);
controller.resumeCamera();
});
}
qr_code_scanner controller got a method called pauseCamera use that to pause camera whenever a valid barcode is detected.
edit: if pauseCamera is not working then you can add boolean variable and switch it to true whenever you get valid QR code. And, navigate to new page only if this variable is false.
I've updated the code, Please take a look.
...
bool gotValidQR = false; //toggle this value when you got a new qr code
...
controller.scannedDataStream.listen((scanData)async {
if(gotValidQR) {
return;
}
gotValidQR = true;
dynamic pop = await Navigator.push(
context,
MaterialPageRoute(builder: (context) {
return ScannedData(data: scanData.code);
}),
);
gotValidQR = false;
});
...
Greeting,
I have a really specific question to ask. I have to explain it with steps and pictures so there they are.
I have an app with three screens:
Main Feed Screen,
Main Chat and Requests Screen,
Main Profile Screen,
And they are all a part of a PageView. This PageView class is controlled inside of a class called main_tab_controller.dart. In that class, in initState(), I have a Firebase Messaging method that is called every time I get a notification (onMessage). So, every time I get this notification, I show an overlay that looks like this.
And it works perfectly on these three main screen. If it's a chat notification, I will direct the PageView to the second screen i.e MainChatAndRequest Screen, and open the chat screen. If it's a request notification, I will direct the PageView to the second screen i.e MainChatAndRequest Screen, and open the requests screen.
But the issue that I am having is the following. In my MainFeedScreen and MainProfileScreen, I have some other screens that I open. For example in MainFeedScreen, I open UserDetailsScreen or FilterScreen. Or in the MainProfileScreen, I open SettingsScreen or EditUserProfileScreen.
So my question is: For example, if I navigate to MainProfileScreen and in that screen open SettingsScreen, and I get the overlay top message, how do I close the SettingsScreen that is currently open and navigate back to the second screen i.e MainChatsAndRequestsScreen from the Firebase Messaging Function that is in initState() of main_tab_controller.dart that is the parent to all of the other screens.
You have the Image Below:
I have tried everything, Navigator.popUntil(context), Navigator.pushReplacement(context), used Navigator.pushNamed(context) but nothing worked. If someone can help me, it would be much appreciated.
Just to give you the better undertanding of the screens:
The Parent Screen is the PageView with three screens:
Main Feed Screen
Main Chat and Requests Screen
Main Profile Screen
and then in Main Feed Screen you have:
Filters Screen
Profile Details Screen
in Main Chat and Requests Screen you have two TabBar Screens:
Chats Screen
Requests Screen
and in Main Profile Screen you have:
Settings Screen
Edit Profiles Screen
PageView Code Snippet:
#override
void initState() {
pageController = PageController(initialPage: _currentIndex);
chatAndRequestController = TabController(length: 2, vsync: this);
var chatAndRequestProvider =
Provider.of<ChatAndRequestProvider>(context, listen: false);
super.initState();
fbm.requestNotificationPermissions();
fbm.configure(
onMessage: (Map<String, dynamic> message) async {
print("onMessage: $message");
bool isRequest;
var mode = (Platform.isIOS) ? message['mode'] : message['data']['mode'];
var imageUrl = '';
switch (mode) {
case 'chat':
isRequest = false;
imageUrl =
chatAndRequestProvider.chatsList.first[kProfilePictureUrl];
break;
case 'sentRequest':
isRequest = true;
imageUrl = (Platform.isIOS)
? message['profilePictureUrl']
: message['data']['profilePictureUrl'];
break;
case 'acceptRequest':
isRequest = false;
imageUrl = (Platform.isIOS)
? message['profilePictureUrl']
: message['data']['profilePictureUrl'];
break;
default:
isRequest = false;
break;
}
AudioCache player = new AudioCache();
const alarmAudioPath = "sounds/notification_sound.mp3";
player.play(alarmAudioPath);
print('Show this ting');
if (_currentIndex != 1) {
if (!isDialogOpen) {
isDialogOpen = true;
_showAnimatedBox(
context,
(Platform.isIOS)
? message['aps']['alert']['title']
: message['notification']['title'],
(Platform.isIOS)
? message['aps']['alert']['body']
: message['notification']['body'],
imageUrl,
isRequest,
);
}
}
},
onLaunch: (Map<String, dynamic> message) async {
print("onLaunch: $message");
},
onResume: (Map<String, dynamic> message) async {
print("onResume: $message");
},
);
notificationPlugin
.setListenerForLowerVersions(onNotificationInLowerVersions);
notificationPlugin.setOnNotificationClick(onNotificationClick);
_children.addAll([
MainFeedScreen(
analytics: widget.analytics,
observer: widget.observer,
latitude: widget.latitude,
longitude: widget.longitude,
),
MainChatAndRequestScreen(
analytics: widget.analytics,
observer: widget.observer,
pageContoller: chatAndRequestController,
),
MainProfileScreen(analytics: widget.analytics, observer: widget.observer),
]);
}
Future _showAnimatedBox(context, topText, bottomText, imageUrl, isRequest) {
showDialog(
context: context,
builder: (BuildContext builderContext) {
_timer = Timer(Duration(seconds: 4), () {
Navigator.of(context).pop();
isDialogOpen = false;
});
return Dismissible(
key: Key('dismissible'),
direction: DismissDirection.up,
onDismissed: (_) {
Navigator.of(context).pop();
isDialogOpen = false;
},
child: FunkyNotification(
() {
var chatAndRequestProvider =
Provider.of<ChatAndRequestProvider>(context, listen: false);
// var contextProv =
// Provider.of<ContextProvider>(context, listen: false);
chatAndRequestProvider.setAreThereNewChatsAndRequestFalse();
if (isRequest) {
pageController.jumpToPage(1);
chatAndRequestController.animateTo(1);
Navigator.of(context).pop();
// Navigator.of(contextProv.context).pop();
// SystemChannels.platform.invokeMethod('SystemNavigator.pop');
// Navigator.popUntil(
// context,
// ModalRoute.withName('/mainProfileScreen'),
// );
// Navigator.of(context)
// .popUntil(ModalRoute.withName('/mainProfileScreen'));
// Navigator.pushAndRemoveUntil(
// context,
// MaterialPageRoute(
// builder: (BuildContext context) => MainTabBarController(
// analytics: null,
// observer: null,
// latitude: 100.23423234,
// longitude: 12.324234234,
// isProfileBlocked: false,
// isVersionGood: true,
// ),
// ),
// (route) => true,
// );
} else {
var chatAndRequestProvider =
Provider.of<ChatAndRequestProvider>(context,
listen: false);
pageController.jumpToPage(1);
chatAndRequestController.animateTo(0);
Navigator.of(context).pop();
Navigator.push(
context,
MaterialPageRoute(
builder: (context) => ChatScreen(
appMode:
chatAndRequestProvider.chatsList.first[kAppMode],
peerId: chatAndRequestProvider.chatsList.first[kUserId],
peerAvatar: chatAndRequestProvider
.chatsList.first[kProfilePictureUrl],
peerName: chatAndRequestProvider
.chatsList.first[kNameAndSurname],
friendshipStatus: chatAndRequestProvider
.chatsList.first['friendsStatus'],
analytics: widget.analytics,
observer: widget.observer,
),
),
);
}
},
topText,
bottomText,
imageUrl,
),
);
}).then((val) {
if (_timer.isActive) {
_timer.cancel();
}
isDialogOpen = false;
});
}
I will try make my answer as general as possible in order to make it easier for others to follow along.
The problem in a nutshell is that you have a nested set of screens distributed between a set of pageviews, and you want to switch between the pageviews from an external event (The overlay in this case).
Below is an example:
TL;DR
I couldn't provide the full code since I don't have your full source code. But here is an example 😉
Note: This example uses Provider.
Sample Event Code
// Remove all the screens in the route
Navigator.of(context).popUntil((route) => route.isFirst); // If the screen is not the first replace the check
// Change the second pageview page
Provider.of<ChatSelectPageView>(context, listen: false).setPage(selectedSecondPageViewPage);
// In case it is required to add intermediate screens between the first and the second pageview it must be added here
// Change the main pageview page
_mainPageViewcontroller.animateToPage(1);
Second PageView
// Reads the page index present in the provider
int selectedPage = Provider.of<ChatSelectPageView>(context, listen: false).page;
// Changes to the cotroller page to the selected page
_pageController.jumpToPage(selectedPage);
ChatSelectPageView
class ChatSelectPageView extends ChangeNotifier {
int page = 0;
void setPage(int _page) {
page = _page;
// Depending on your implementation it might be better to remove this line to reduce the number of builds
notifyListeners();
}
}
TS;WM
In order to achieve the desired behavior, there is multiple ways to achieve it. If we want to stick to your implementation we will be a bit constrained. But in this case what I would suggest you do is to use some kind of global state management library such as provider, it can be done without any library but the state will get very messy very quickly.
As you mentioned above you tried Navigator.popUntil but it didn't work, I suspect the reason for this is that you are providing the wrong context. Since Navigator.**** relies on the context to work, i.e. to pop a screen you must provide its context. Or the route check is wrong.
This code is to be written in the external event in your case it will be written in the click listener of the overlay.
Use a state management solution such as Provider to pass the state to the descendants of the main Pageview down to the screens. This provider will be of type ChangeNotifierProvider. When the overlay is clicked, a flag will be set to be the desired pageview page index (I am speaking about the 2nd pageview). In your case this flag is used to select chats or requests.
After that is done you call Navigator.of(context).popUntil((route) => route.isFirst); assuming that the pageview is present on the first page of your app. In the case where it is not on that page, you will have to use Navigator.of(context).popUntil() with a custom logic.
After that we will have to navigate back to the 2nd pageview, or change the first pageview to be the 2nd page in your case. The second pageview will be already switched since we changed the flag in provider before.
I have a problem implementing a login button, when I press it, it will not function at first, but when I press it again (same value fields) it works.
here's my code
Button:
Center(child: RaisedButton(onPressed: (){
setState(() {
onPressedLogin(userName.text,password.text);
});
}
The OnPressedLogin():
void onPressedLogin(String userName,String password) async{
bool isValid = false;
var value = await dataBaseHelper.getUserList();
for(User userOB in value){
//print(userOB.password+" "+password),
if(userName == userOB.username && password == userOB.password) {
isValid = true;
this.password.clear();
this.userName.clear();
inputTextColor = Colors.grey[850];
invalidCredentials = "";
print("YES");
//Navigator.push(context, MaterialPageRoute(builder: (context) => Home()));
break;
}
}
if(!isValid){
inputTextColor = Colors.red[800];
invalidCredentials = "Invalid Credentials";
}
You are using a Future but in setState() you are not waiting for it so that's way it work in the second press (the value take time to change).
To make it work with single press you have to a wait the Future to complete before rebuilding, here how:
First change the return type of the function
Future<void> onPressedLogin(String userName,String password)
Then in the RaisedButton
onPressed: () async {
await onPressedLogin(userName.text,password.text);
setState(() {});
},
The moment you setState(), the UI will refresh!
Probably that's the issue, let me explain:
What you should do is to call your function before setState(), so that the screen is refreshed with the new info.
Center(child: RaisedButton(onPressed: (){
onPressedLogin(userName.text,password.text);
setState(() {
//Variables that change for the refresh.
});
}
In your specific case, I don't see the need for SetState() as you are only printing values in log, not changing the UI.
Hope it is helpful.