FutureBuilder only works in Debug - flutter

Question

I have a FutureBuilder with a ListView to display custom items (Widgets) with values which are read from .txt files.
The problem is that these items are only displayed if I launch the app in Debug-mode or run-mode. When I try to open the app with the AppLauncher (like a "normal" user would do it) the listView is empty. I tried this on an AVD and on a "real" device.
the Future "listFuture" is used to read the values from the files and return a list of Widgets
class Home extends StatefulWidget {
final Future listFuture = setupList();
#protected
#mustCallSuper
void initState() {
print("init complete");
}
#override
State<StatefulWidget> createState() {
return HomeState();
}
}
If the FutureBuilder gets the data correctly a listView with the list of my widgets should be displayed
child: FutureBuilder<List<SubListItem>>(
future: widget.listFuture,
// ignore: missing_return
builder: (BuildContext context, AsyncSnapshot snapshot) {
switch (snapshot.connectionState) {
case ConnectionState.none:
return new Text("None");
case ConnectionState.waiting:
return new Text("loading");
default:
if (snapshot.hasError) {
print("Error");
return Center(child: (Text("No data")));
} else {
return subListView(context, snapshot);
}
}
},
),
Widget subListView(BuildContext context, AsyncSnapshot snapshot) {
List<Widget> items = snapshot.data;
//This ScrollConfiguration is used to remove any animations while scrolling
return ScrollConfiguration(
behavior: CustomScrollBehavior(),
child: Container(
padding: EdgeInsets.symmetric(horizontal: 4),
child: new ListView.builder(
itemCount: items.length,
itemBuilder: (BuildContext context, int index) {
return Column(
children: <Widget>[items[index]],
);
},
),
),
);
}
Thanks for helping!

Answer 1

Ok, I solved the problem. You just have to call "setState" when your Widget is built.
#protected
#mustCallSuper
void initState() {
super.initState();
Future.delayed(Duration.zero, () {
//This setState is necessary because it refreshes the listView
setState(() {});
});
}

Answer 2

It's looks like a async data issue, try these changes:
Remove listFuture from your StatefulWidget.
Add the listFuture var inside your State.
Move the setupList() method inside your State.
And finally call directly like this:
child: FutureBuilder<List<SubListItem>>(
future: setupList(),
// ignore: missing_return
builder: (BuildContext context, AsyncSnapshot snapshot) {
if(!snapshot.hasData) {
return new Text("loading");
}
else if (snapshot.hasError) {
print("Error");
return Center(child: (Text("No data")));
} else {
return subListView(context, snapshot);
}
}
},
),