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Hello everyone,
hoping you are ok, i need your help, i get this error There are multiple heroes that share the same tag within a subtree every time i navigate to another page
being on MyIdemDetailsScreen I call my appbar,
class _MyItemDetailsScreenState extends State<MyItemDetailsScreen> {
// ignore: prefer_typing_uninitialized_variables
final GlobalKey<FormState> _forKey = GlobalKey<FormState>();
TextEditingController counterTextEditingController = TextEditingController();
forValidation() {
if (counterTextEditingController.text.isNotEmpty) {
int itemCounter = int.parse(counterTextEditingController.text);
List<String> separateItemIDsList = separateItemIDs();
//1.check if item exist already in cart
separateItemIDsList.contains(widget.model!.itemID)
? Fluttertoast.showToast(msg: "Item is already in Cart.")
:
//2.add to cart
addItemToCart(widget.model!.itemID, context, itemCounter);
} else {
showDialog(
context: context,
builder: (c) {
return ErrorDialog(
message: "Metter une valeur",
);
});
}
}
@override
Widget build(BuildContext context) {
return Scaffold(
resizeToAvoidBottomInset: false,
appBar: const MyAppBar(),// i call my appbar here
body: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: [
Padding(
padding: const EdgeInsets.all(8.0),
child: Card(
shape: const RoundedRectangleBorder(
borderRadius: BorderRadius.all(Radius.circular(8.0))),
child: InkWell(
child: Column(
crossAxisAlignment: CrossAxisAlignment.stretch,
children: <Widget>[
ClipRRect(
borderRadius: const BorderRadius.only(
topLeft: Radius.circular(8.0),
topRight: Radius.circular(8.0),
),
child: Image.network(
widget.model!.thumbnailUrl.toString(),
height: 290,
fit: BoxFit.fill),
),
ListTile(
title: Text(
textAlign: TextAlign.left,
widget.model!.title.toString().toUpperCase(),
style: const TextStyle(
fontWeight: FontWeight.bold, fontSize: 20),
),
subtitle: Text(
textAlign: TextAlign.left,
widget.model!.shortInfo.toString(),
style: const TextStyle(
fontWeight: FontWeight.bold, fontSize: 20)))
],
),
),
),
),
Padding(
padding: const EdgeInsets.all(18.0),
child: Form(
key: _forKey,
child: Column(
children: [
TextFormField(
decoration:
const InputDecoration(labelText: "Enter your number"),
keyboardType: TextInputType.number,
controller: counterTextEditingController,
inputFormatters: [
FilteringTextInputFormatter.allow(
RegExp("[0-9]"),
),
],
),
],
)),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Text(
widget.model!.longDescription.toString(),
textAlign: TextAlign.justify,
style:
const TextStyle(fontWeight: FontWeight.normal, fontSize: 14),
),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Text(
"${widget.model!.price} CDF",
style: const TextStyle(fontWeight: FontWeight.bold, fontSize: 30),
),
),
const SizedBox(
height: 10,
),
Center(
child: InkWell(
onTap: () {
forValidation();
},
child: Container(
decoration: const BoxDecoration(
gradient: LinearGradient(
colors: [
Colors.cyan,
Colors.amber,
],
begin: FractionalOffset(0.0, 0.0),
end: FractionalOffset(1.0, 0.0),
stops: [0.0, 1.0],
tileMode: TileMode.clamp,
)),
width: MediaQuery.of(context).size.width - 13,
height: 50,
child: const Center(
child: Text(
"Add to Cart",
style: TextStyle(color: Colors.white, fontSize: 15),
),
),
),
),
),
],
),
);
}
}
here is the code of my appbar
class _MyAppBarState extends State<MyAppBar> {
@override
Widget build(BuildContext context) {
return AppBar(
flexibleSpace: Container(
decoration: const BoxDecoration(
gradient: LinearGradient(
colors: [
Colors.cyan,
Colors.amber,
],
begin: FractionalOffset(0.0, 0.0),
end: FractionalOffset(1.0, 0.0),
stops: [0.0, 1.0],
tileMode: TileMode.clamp,
)),
),
leading: IconButton(
onPressed: () {
Navigator.pop(context);
},
icon: const Icon(Icons.keyboard_backspace_outlined)),
title: const Text(
"iFood",
style: TextStyle(
fontSize: 45, fontFamily: "Signatra", color: Colors.white),
),
centerTitle: true,
automaticallyImplyLeading: true,
actions: [
Stack(
children: [
IconButton(
icon: const Icon(
Icons.shopping_cart,
color: Colors.cyan,
),
onPressed: () {
//send user to cart screen
Navigator.push(
context,
MaterialPageRoute(
builder: (c) => CartItem(ifoodUID: widget.ifoodUID)));
},
),
Positioned(
child: Stack(
children: [
const Icon(
Icons.brightness_1,
size: 20.0,
color: Colors.green,
),
Positioned(
top: 3,
right: 4,
child: Center(
child: Consumer<CartItemCounter>(
builder: (context, counter, c) {
return Text(
counter.count.toString(),
style: const TextStyle(
color: Colors.white, fontSize: 12),
);
},
),
),
),
],
),
),
],
),
],
);
}
}
and I call CartItem page
@override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
flexibleSpace: Container(
decoration: const BoxDecoration(
gradient: LinearGradient(
colors: [
Colors.cyan,
Colors.amber,
],
begin: FractionalOffset(0.0, 0.0),
end: FractionalOffset(1.0, 0.0),
stops: [0.0, 1.0],
tileMode: TileMode.clamp,
)),
),
leading: IconButton(
icon: const Icon(Icons.clear_all),
onPressed: () {
clearCartNow(context);
},
),
title: const Text(
"iFood",
style: TextStyle(fontSize: 45, fontFamily: "Signatra"),
),
centerTitle: true,
automaticallyImplyLeading: true,
actions: [
Stack(
children: [
IconButton(
icon: const Icon(
Icons.shopping_cart,
color: Colors.cyan,
),
onPressed: () {
print("clicked");
},
),
Positioned(
child: Stack(
children: [
const Icon(
Icons.brightness_1,
size: 20.0,
color: Colors.green,
),
Positioned(
top: 3,
right: 4,
child: Center(
// child: Consumer<CartItemCounter>(
// builder: (context, counter, c)
// {
// return Text(
// counter.count.toString(),
// style: const TextStyle(color: Colors.white, fontSize: 12),
// );
// },
// ),
),
),
],
),
),
],
),
],
),
floatingActionButton: Center(
child: Stack(
children: [
RadialMenu(
centerButtonAlignment: Alignment
.bottomCenter, // by default alignment is set to Alignment.center
centerButtonSize: 0.5, // size ranging from 0.0 to 1.0
children: [
RadialButton(
icon: const Icon(Icons.navigate_next),
buttonColor: Colors.teal,
onPress: () {
clearCartNow(context);
// Navigator.push(context, MaterialPageRoute(builder: (c)=> const MySplashScreen()));
Fluttertoast.showToast(msg: "Cart has been cleared.");
}),
RadialButton(
icon: const Icon(Icons.clear_all),
buttonColor: Colors.green,
onPress: () {}),
/* you can add any number of buttons, although it's
not recommended to insert beyond 8-9 buttons. */
],
),
],
)),
body: const Center());
}
and I always get this exception, please can you help me,
I’ve been thinking about this expression for days, and I can’t fix it,
2
Answers
Generally, the usual cause of that error are
Floating Action Buttons (FAB)s.traverse your application screens again searching for any FAB and provide a unique hero tag for each FAB.
if you have many
FABs in your app, the above code will be error-prone because it may lead to unintended duplicate of the sameheroTag.So i recommend the following :
Ante todo pedir disculpas si lo explico muy mal llevo solo un año con flutter y nunca tuve estudios antes ni siquiera ingles …
llevo mucho tiempo con este error ======== Exception caught by scheduler library ===================================================== The following assertion was thrown during a scheduler callback: There are multiple heroes that share the same tag within a subtree. Within each subtree for which heroes are to be animated (i.e. a PageRoute subtree), each Hero must have a unique non-null tag. In this case, multiple heroes had the following tag: Here is the subtree for one of the offending heroes: Hero tag: state: _HeroState#5b697 When the exception was thrown, this was the stack:
y quería compartir mi solución…
1º Busque y aquí se explica muy bien como solucionarlo https://stackoverflow.com/questions/51125024/there-are-multiple-heroes-that-share-the-same-tag-within-a-subtree
Pero… no había manera y no daba con la solución y me estaba volviendo loco porque parecía que el error se causaba al entrar a VistaPrevia(), Básicamente es donde se muestra una imagen seleccionada de la vista anterior.
Esta VistaPrevia(), Tenia muchos botones de diferentes opciones ….
`FloatingActionButton.extended(
heroTag: ‘rotar’,
/…
FloatingActionButton.extended(
heroTag: ‘subir’,
/…
FloatingActionButton.extended(
heroTag: ‘bajar’,
/…`
esa se suponia que era la solucion, o sea, colocar a cada uno heroTag: ‘bajar’, heroTag: ‘subir’,heroTag: ‘rotar’,… Que tambien, pero me olvide de lo mas Tonto, La vista desde donde venia que era VistaPrincipal(),
Hi tenia un botoncito…. #@#¢, si el botoncito
FloatingActionButton.extended( heroTag: 'ir vista principal', /..Donde , heroTag: ‘ir vista principal’, evidentemente no estaba…
Pues lo dicho esta es mi experiencia con ese error que me ha traido de cabeza y espero que esto os sirva para solucionarlo