Flutter- how to get currentValue out of FlutterSlider (flutter_xlider) - flutter

Question

I am using the flutterSilder dependency since it gives me the possibility to use "FluterSliderSteps", making a non linear increase of the value possible (exponential).
Now I got the problem that I don't know how to get the current value out of the slider, in order to use it to display the value as text elsewhere or to save/use it.
Underneath I put some basic code, displaying the foundations. There is a padding field class with a text field on the top that saying "myFeedbackText" which should display the value instead. Does anybody have an Idea? Thank you! https://pub.dev/packages/flutter_xlider
class flutterSlider extends StatefulWidget {
#override
_flutterSliderState createState() => _flutterSliderState();
}
class _flutterSliderState extends State<flutterSlider> {
RangeValues range = RangeValues(1, 100);
double slide = 2;
#override
Widget build(BuildContext context) {
return new Scaffold(
body: Container(
color: Color(0xffE5E5E5),
child: Center(
child: Container(
child: Align(
child: Material(
color: Colors.white,
elevation: 14.0,
borderRadius: BorderRadius.circular(24.0),
shadowColor: Color(0x802196F3),
child: Container(
width: 350.0,
height: 400.0,
child: Column(
children: <Widget>[
SizedBox(height: 30,),
Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
child: Text(
"myFeedbackText", // should display currentValue
style: TextStyle(
color: Colors.black, fontSize: 22.0),
)),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
child: Builder( //Needed to find Scaffold.of(context) and display the snackbar
builder: (BuildContext context) {
return FlutterSlider(
values: [300],
max: 500,
min: 0,
onDragging: (handlerIndex, lowerValue, upperValue) {
setState(() {});
},
step: FlutterSliderStep(
step: 1, // default
isPercentRange: true, // ranges are percents, 0% to 20% and so on... . default is true
rangeList: [
FlutterSliderRangeStep(from: 0, to: 100, step: 1),
FlutterSliderRangeStep(from: 100, to: 300, step: 5),
FlutterSliderRangeStep(from: 300, to: 500, step: 10),
]
),
);
}
),
),
),
],
)),
),
),
),
),
),
);
}
}

Answer 1

You can copy paste run full code below
You can define a variable _lowerValue and update it with onDragging and onDragCompleted
code snippet
double _lowerValue = 300;
...
Container(
child: Text(
"$_lowerValue",
...
FlutterSlider(
values: [_lowerValue],
max: 500,
min: 0,
onDragging:
(handlerIndex, lowerValue, upperValue) {
setState(() {
_lowerValue = lowerValue;
});
},
onDragCompleted:
(handlerIndex, lowerValue, upperValue) {
setState(() {
_lowerValue = lowerValue;
});
},
working demo
full code
import 'package:flutter/material.dart';
import 'package:flutter_xlider/flutter_xlider.dart';
class flutterSlider extends StatefulWidget {
#override
_flutterSliderState createState() => _flutterSliderState();
}
class _flutterSliderState extends State<flutterSlider> {
RangeValues range = RangeValues(1, 100);
double slide = 2;
double _lowerValue = 300;
#override
Widget build(BuildContext context) {
return new Scaffold(
body: Container(
color: Color(0xffE5E5E5),
child: Center(
child: Container(
child: Align(
child: Material(
color: Colors.white,
elevation: 14.0,
borderRadius: BorderRadius.circular(24.0),
shadowColor: Color(0x802196F3),
child: Container(
width: 350.0,
height: 400.0,
child: Column(
children: <Widget>[
SizedBox(
height: 30,
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
child: Text(
"$_lowerValue", // should display currentValue
style:
TextStyle(color: Colors.black, fontSize: 22.0),
)),
),
Padding(
padding: const EdgeInsets.all(8.0),
child: Container(
child: Builder(
//Needed to find Scaffold.of(context) and display the snackbar
builder: (BuildContext context) {
return FlutterSlider(
values: [_lowerValue],
max: 500,
min: 0,
onDragging:
(handlerIndex, lowerValue, upperValue) {
setState(() {
_lowerValue = lowerValue;
});
},
onDragCompleted:
(handlerIndex, lowerValue, upperValue) {
setState(() {
_lowerValue = lowerValue;
});
},
step: FlutterSliderStep(
step: 1, // default
isPercentRange:
true, // ranges are percents, 0% to 20% and so on... . default is true
rangeList: [
FlutterSliderRangeStep(
from: 0, to: 100, step: 1),
FlutterSliderRangeStep(
from: 100, to: 300, step: 5),
FlutterSliderRangeStep(
from: 300, to: 500, step: 10),
]),
);
}),
),
),
],
)),
),
),
),
),
),
);
}
}
void main() {
runApp(MyApp());
}
class MyApp extends StatelessWidget {
#override
Widget build(BuildContext context) {
return MaterialApp(
title: 'Flutter Demo',
theme: ThemeData(
primarySwatch: Colors.blue,
visualDensity: VisualDensity.adaptivePlatformDensity,
),
home: flutterSlider(),
);
}
}
class MyHomePage extends StatefulWidget {
MyHomePage({Key key, this.title}) : super(key: key);
final String title;
#override
_MyHomePageState createState() => _MyHomePageState();
}
class _MyHomePageState extends State<MyHomePage> {
int _counter = 0;
void _incrementCounter() {
setState(() {
_counter++;
});
}
#override
Widget build(BuildContext context) {
return Scaffold(
appBar: AppBar(
title: Text(widget.title),
),
body: Center(
child: Column(
mainAxisAlignment: MainAxisAlignment.center,
children: <Widget>[
Text(
'You have pushed the button this many times:',
),
Text(
'$_counter',
style: Theme.of(context).textTheme.headline4,
),
],
),
),
floatingActionButton: FloatingActionButton(
onPressed: _incrementCounter,
tooltip: 'Increment',
child: Icon(Icons.add),
),
);
}
}