Flutter - How can I call setState when a future builder has completed? - flutter

Question

I have a widget which is getting data from one of my other classes(booruHandler), I am using the search function for the future of a future builder but I need it to be called multiple times but only once the future builder has completed, I am using a similar future builder in another widget and getting it to call again using setState to increment widget.pageNum when an action happens. Is there a way to make it so the setState gets called when the future builder has finished building? I tried putting setState inside the futurebuilder and making it call if the connectionState is done but that doesn't work
class SnatcherProgressPage extends StatefulWidget {
String tags,amount,timeout;
int pageNum=0;
int count=0;
SnatcherProgressPage(this.tags,this.amount,this.timeout);
#override
_SnatcherProgressPageState createState() => _SnatcherProgressPageState();
}
class _SnatcherProgressPageState extends State<SnatcherProgressPage> {
static int limit, count;
#override
void initState() {
// TODO: implement initState
super.initState();
if (int.parse(widget.amount) <= 100){limit = int.parse(widget.amount);} else {limit = 100;}
}
BooruHandler booruHandler = new GelbooruHandler("https://gelbooru.com", limit);
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text("Snatching"),
),
body: FutureBuilder(
future: booruHandler.Search(widget.tags,widget.pageNum),
builder: (context, AsyncSnapshot snapshot){
switch(snapshot.connectionState){
case ConnectionState.active:
return Text("Snatching");
break;
case ConnectionState.done:
if (snapshot.data.length < int.parse(widget.amount)){
// Inc pagenum to get more data
// Call the writer function on all of the data
}
return Text(snapshot.data.length.toString());
break;
case ConnectionState.waiting:
return CircularProgressIndicator();
break;
case ConnectionState.none:
return Text("hmmmmmm");
break;
}
return Text("hmmmmmm");
},
),
);
}
}

Answer 1

very nice example could be like this:
final navigatorKey = GlobalKey<NavigatorState>();
void main() => runApp(
MaterialApp(
home: HomePage(),
navigatorKey: navigatorKey, // Setting a global key for navigator
),
);
class HomePage extends StatelessWidget {
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(),
body: SafeArea(
child: Center(
child: Text('test')
)
),
floatingActionButton: FloatingActionButton(
onPressed: showMyDialog, // Calling the function without providing it BuildContext
),
);
}
}
void showMyDialog() {
showDialog(
context: navigatorKey.currentContext,
builder: (context) => Center(
child: Material(
color: Colors.transparent,
child: Text('Hello'),
),
)
);
}
showMyDialog() could be used everywhere including static Utility classes, db connection classes etc...

Answer 2

Call back pageNum when updating
class SnatcherProgressPage extends StatefulWidget {
final NumberCallBack onPageNumUpdated;
}
// ...
setState((){
onPageNumUpdated(/* the number */);
});
// ...
typedef NumberCallBack = void Function(int number);
Or use state management