Flutter how to refresh appBar Title after FutureBuilder - flutter

Question

Is it possible to refresh appBar title after widget FutureBuilder ?
I'd like to set title after FutureBuilder is done
class _SimpleBarChart extends State<SimpleBarChartPage> {
String _appBarTitle = '';
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(title: Text(_appBarTitle)),
body: Center(child: futureCAGraph()));
}
futureCAGraph() {
return FutureBuilder(
future: BddAMKGraphCA().getDataGraphCA(_caAnnee),
builder: (context, AsyncSnapshot<List<dynamic>> snapshot) {
if (snapshot.hasData) {
return ListView.builder(
itemCount: snapshot.data!.length,
itemBuilder: (context, int currentIndex) {
return affGraphCA(context);
});
} else if (snapshot.hasError) {
return Text('${snapshot.error}');
}
//return a circular progress indicator.
return new CircularProgressIndicator();
});
}

Answer 1

You Just Have to update Text(_appBarTitle) with Text(snapshot.data[Index].title)

Answer 2

you can easily update it with setstate() after you get data from future. just assign _appBarTitle in setstate() as shown below,
setState(() {
_appBarTitle=//assign your snapshot data
});

Answer 3

It's not a good practice to call setState during the build method. Instead you can move Scaffold inside the builder like this:
Widget build(BuildContext context) {
return FutureBuilder(
future: BddAMKGraphCA().getDataGraphCA(_caAnnee),
builder: (context, AsyncSnapshot<List<dynamic>> snapshot)
=> Scaffold(
appBar: AppBar(title: Text(_appBarTitle)),
body: Center(child: (snapshot.hasData)
? ListView.builder(
itemCount: snapshot.data!.length,
itemBuilder: (context, int currentIndex) {
return affGraphCA(context);
})
: (snapshot.hasError)
? Text('${snapshot.error}')
: //return a circular progress indicator.
CircularProgressIndicator(),
),
)
);
}

Answer 4

Sorry, after testing appBar's title don't print anything
Widget build(BuildContext context) {
return FutureBuilder(
future: BddAMKGraphCA().getDataGraphCA(_caAnnee),
builder: (context, AsyncSnapshot<List<dynamic>> snapshot)
=> Scaffold(
appBar: AppBar(title: Text(_appBarTitle)),
body: Center(child: (snapshot.hasData)
? ListView.builder(
itemCount: snapshot.data!.length,
itemBuilder: (context, int currentIndex) {
**print('appBar something');**
return affGraphCA(context);
})
: (snapshot.hasError)
? Text('${snapshot.error}')
: //return a circular progress indicator.
CircularProgressIndicator(),
),
)
);
}