How to fetch/retrieve array Firestore and display on flutter using Getx - firebase

Question

I have a restaurant on my collection field, this restaurant has a single offer for example
'15% Discount' I have already displayed this part on my flutter app.
Now let's say I have another restaurant who has multiple offer {'0': 'DISCOUNT 5%', '1': 'DISCOUNT 10%'} how would I go to display it on my app, I tried the following but it didn't work
Here is my collection offer field
Here is the code :
class OfferModel {
String id;
List offer;
OfferModel({
this.id,
this.offer,
});
factory OfferModel.fromJson(Map<String, dynamic> json, elementId) =>
OfferModel(
id: elementId,
offer: json ['offer'],
);
Map<String, dynamic> toJson() => {
"offer": offer,
};
class OfferDetail extends StatelessWidget {
final OfferModel currentOffer;
OfferDetail(this.currentOffer);
final controller = Get.put(OfferDetailController());
#override
Widget build(BuildContext context) {
controller.offer = currentOffer;
Widget offerSection = Container(
child: Text(
currentOffer.offer,
);
return Scaffold(
body: Stack(
children: [
Column(
children: [
Expanded(
child: ListView(
children: [
offerSection,
Padding(
padding:
EdgeInsets.symmetric(vertical: 15, horizontal: 15),
child: Align(
child: ButtonFayda(
title: 'Get offer',
onPressed: () {
controller.offerId = currentOffer.id;
controller.claimOffer();
},
),
alignment: Alignment.bottomCenter,
),
),
],
),
),
],
)
],
),
);
}
}
class OfferDetailController extends GetxController {
var offer = OfferModel();
var offerId;
RxList<OfferModel> offerList = <OfferModel>[].obs;
var isLoading = true.obs;
//rest of the code
}

Answer 1

I could not understand your code but I could understand your question as below.
You have a object like this
Object{
field1 String,
field2 List<String>
}
In you Firestore you have the data for the respective object. Now you would like to know how to fetch the field2 array.
So this can be achieved using List.castFrom(data['field2']).
For example
QuerySnapshot<Map<String, dynamic>> data = await FirebaseFirestore.instance.collection('object').get();
List<Object> objList = data.docs.map<Object>((data) =>
new Shop(
field1: data['field1'],
field2: List.castFrom(data['field2'])
)
).toList();