Unable to retrieve firebase data to Listview - firebase

Question

I am trying to retrieve data from my real-time firebase into a listview.
The Firebase Json Tree:
I want to retrieve Item, Expiry Date and Quantity in the listview format.
My code is as follows:
var lists = [];
final database = FirebaseDatabase(
databaseURL: "https://trackkit-a5cf3-default-rtdb.asia-southeast1.firebasedatabase.app")
.reference()
.child('Location 1');
#override
Widget build(BuildContext context) {
return Scaffold(
body: Container(
child: StreamBuilder(
stream: database.onValue,
builder: (context, AsyncSnapshot<Event> snapshot) {
if (snapshot.hasData && !snapshot.hasError &&
snapshot.data!.snapshot.value != null) {
print("Error on the way");
lists.clear();
DataSnapshot dataValues = snapshot.data!.snapshot;
Map<dynamic, dynamic> values = dataValues.value;
values.forEach((key, values) {
lists.add(values);
});
return ListView.builder(
shrinkWrap: true,
itemCount: lists.length,
itemBuilder: (BuildContext context, int index) {
return Card(
child: Column(
crossAxisAlignment: CrossAxisAlignment.start,
children: <Widget>[
Text("Item: " + lists[index]["Item"]),
Text("Expiry Date: " + lists[index]["Expiry Date"]),
Text("Quantity: " + lists[index]["Quantity"]),
],
),
);
},
);
}
return Container(child: Text("Add Items"));
},
),
),
);
}
The current screen shows :
type 'int' is not a subtype of type 'String'
I have been trying for days! Any help would be greatly appreciated.

Answer 1

Maybe you are getting a Integer value in return to your lists[index]["Quantity"]. And you cannot concat and integer with String without converting into a String.
So Please use method toString() with lists[index]["Quantity"] to make it work properly.

Answer 2

You have to Quantity make a String value, use toString() method on it in Text Widget,
like that: Text("Quantity: " + lists[index]["Quantity"].toString())