return new futureBuilder keeps requesting to the server on screen size change - flutter

Question

I'm building an app which has a bottomBar that request data from the server, and when I change the size of the screen it request again to the server
this is my bottomBar Widget
Widget bottomNavigationBar() {
return new BottomAppBar(
color: const Color(0xFF1E90FF),
child: new Row(
mainAxisAlignment: MainAxisAlignment.spaceBetween,
children:[
Container(
padding: EdgeInsets.only(left: 20),
child: futureBuilderWidget(setVersion())
),
Container(
child: Text(
DateFormat('yyyy-MM-dd hh:mm:ss').format(DateTime.now()),
style: TextStyle( fontSize: 16, color: const Color(0xffebebeb))
),
),
],
),
);
}
And this is my futureBuilder widget
Widget futureBuilderWidget(_future) {
return new FutureBuilder<dynamic>(
future: _future,
builder: (BuildContext context, AsyncSnapshot<dynamic> snapshot) {
if (snapshot.connectionState == ConnectionState.done) {
if (snapshot.hasError) {
return Text(
snapshot.error.toString(),
style: TextStyle(fontSize: 16, color: const Color(0xffebebeb)),
);
} else if (snapshot.hasData) {
return Text(snapshot.data,
style: TextStyle(fontSize: 16, color: const Color(0xffebebeb)),
);
}
}
return CircularProgressIndicator();
},
);
}
Is there anyway in which I could just ask once?

Answer 1

Place future inside init() state. It will run only once I hope. PS: Don't put it in setState() it will run every time your screen regenerates.

Answer 2

I assume that the _future contains an HTTP request. As mentioned in the FutureBuilder docs, future should be obtained earlier.
The future must have been obtained earlier, e.g. during State.initState, State.didUpdateWidget, or State.didChangeDependencies. It must not be created during the State.build or StatelessWidget.build method call when constructing the FutureBuilder. If the future is created at the same time as the FutureBuilder, then every time the FutureBuilder's parent is rebuilt, the asynchronous task will be restarted.
What you can do here is either run the request on initState() and update Future<dynamic> _future with a setState() to trigger a widget rebuild, or use async package to only run the request once.
final AsyncMemoizer _memoizer = AsyncMemoizer();
Future<dynamic> _future() {
return _memoizer.runOnce(() async {
// Do the request
});
}