Flutter ListView delete Items not working - list

Question

I have a ListView.builder with widgets and I would like to remove items from it but when I execute the Lines below nothing happens.
if (mounted) {
setState(() {
verlustContentList.removeLast();
});
}
This is how I generate the List:
generateList() async {
return verlustContentList = List.generate(
15,
(index) => VerlustContent(
key: Key(
index.toString(),
),
),
);
}
This is how I display the List:
StreamBuilder(
stream: generateList().asStream(),
builder: (BuildContext context, AsyncSnapshot snapshot) {
return ListView.builder(
itemCount: verlustContentList.length,
itemBuilder: (context, index) {
return verlustContentList[index];
},
);
},
);
The Class VerlustContent is a Statefulwidget.

Answer 1

StreamBuilder listens to a stream you defined but you never push new data to that stream.
If you would print the list after the .removeLast(), it would really print the list without the last one.
I think you should remove the StreamBuilder because you can't even access that stream this way. Generate the list on initState() and show it in ListView. If generation does take some time, you can return a CircularProgressIndicator() if list is empty.
class MyStateful extends StatefulWidget {
#override
_MyStatefulState createState() => _MyStatefulState();
}
class _MyStatefulState extends State<MyStateful> {
List<Text> list= [];
#override
void initState() {
super.initState();
generateList();
}
void generateList() {
list = List.generate(
15,
(index) => Text(
index.toString()
),
);
}
#override
Widget build(BuildContext context) {
return MaterialApp(
home: Scaffold(
body: Center(
child: Column(
children: [
Container(
height: 300,
child: ListView.builder(
itemCount: list.length,
itemBuilder: (context, index) {
return list[index];
},
),
),
ElevatedButton(
onPressed: () {
if (mounted) {
setState(() {
list.removeLast();
print(list);
});
}
},
child: Text('deleteLast'),
),
],
),
),
),
);
}
}