flutter cannot acces a method of another class using static access - flutter

Question

title basically explains the error method i'm recieving. sorry for the huge code, but i'm basically just trying to make a call to onboarding to flip the page when a user touches the "next" text. (onTap:() => _OnboardingState.jumpForward())"
how can i do this?
i've tried using streams (i'm pretty bad with it) and maybe a solution would be bloc related. idk. i'm sure it's a pretty easy fix
import 'package:flutter/material.dart';
import '../../styling/canvas.dart';
import '../../styling/theme.dart';
import 'dart:async';
class Onboarding extends StatefulWidget {
#override
_OnboardingState createState() => _OnboardingState();
}
class _OnboardingState extends State<Onboarding> {
PageController onboardingController;
void jumpForward() async {
onboardingController.nextPage(
curve: Curves.easeIn,
duration: Duration(milliseconds: 200)
);
}
#override
Widget build(BuildContext context) {
return PageView(
controller: onboardingController,
pageSnapping: true,
children: <Widget>[
OnboardingPage(viewModel:pages[0]),
OnboardingPage(viewModel:pages[1]),
OnboardingPage(viewModel:pages[2]),
]
);
}
// jumpTo() {
// hello.jump
// }
}
class PageViewModel{
PageViewModel({
this.title,
this.description,
this.id,
});
final String title;
final String description;
final int id;
}
final pages = [
PageViewModel(
title: "Trade smart",
description:
"Filter stocks by metrics like short interest and short interest change.",
id: 1,
),
PageViewModel(
title: "Connect",
description:
"Filter stocks by metrics like short interest and short interest change.",
id: 2,
),
PageViewModel(
title: "Get an edge",
description:
"View legal insider trades filed with the SEC, made by top executives.",
id: 3,
),
];
class OnboardingPage extends StatelessWidget {
OnboardingPage({this.viewModel});
final PageViewModel viewModel;
#override
Widget build(BuildContext context) {
double _height = MediaQuery.of(context).size.height;
double _width = MediaQuery.of(context).size.width;
final double _circleHeight = .022 * _height;
return Scaffold(
body: Container(
color: lightTheme.backgroundColor,
height: _height,
width: _width,
child: Padding(
padding: EdgeInsets.fromLTRB(0.0, .1 * _height, 0.0, .1 * _height),
child: Column(
children: <Widget>[
Padding(
padding: EdgeInsets.fromLTRB(
.044 * _width, 0.0, .044 * _width, .022 * _height),
child: Container(
//illustration
decoration:
returnCanvasStyle(), //todo: change color to theme bloc
width: _width,
height: .433 * _height,
),
),
Padding(
padding:
EdgeInsets.fromLTRB(.044 * _width, 0.0, .044 * _width, 0.0),
child: Container(
decoration: returnCanvasStyle(),
width: _width,
height: .344 * _height, //todo: change height
child: Column(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.start,
children: <Widget>[
Padding(
padding: EdgeInsets.fromLTRB(0.022 * _width,
0.022 * _height, 0.022 * _width, 0.0),
child: Text(
viewModel.title,
style: lightTheme.primaryTextTheme.display1,
textAlign: TextAlign.center,
),
),
Padding(
padding: EdgeInsets.fromLTRB(0.044 * _width,
0.022 * _height, 0.044 * _width, 0.033 * _height),
child: Text(
viewModel.description,
style: lightTheme.primaryTextTheme.body1,
softWrap: true,
textAlign: TextAlign.center,
),
),
Row(
crossAxisAlignment: CrossAxisAlignment.center,
mainAxisAlignment: MainAxisAlignment.end,
children: <Widget>[
Padding(
padding: EdgeInsets.fromLTRB(
0.0, 0.0, .066 * _width, 0.0),
child: Container(
width: _circleHeight,
height: _circleHeight,
//color: Colors.red,
decoration: BoxDecoration(
border: Border.all(
color: lightTheme.primaryColor,
width: .0055 * _height,
),
borderRadius: BorderRadius.all(
Radius.circular(_circleHeight)),
color: lightTheme.primaryColor),
),
),
Padding(
padding: EdgeInsets.fromLTRB(
0.0, 0.0, .066 * _width, 0.0),
child: Container(
width: _circleHeight,
height: _circleHeight,
//color: Colors.red,
decoration: BoxDecoration(
border: Border.all(
color: lightTheme.primaryColor,
width: .0055 * _height,
),
borderRadius: BorderRadius.all(
Radius.circular(_circleHeight)),
color: Colors.transparent),
),
),
Padding(
padding: EdgeInsets.fromLTRB(
0.0, 0.0, .0944 * _width, 0.0),
child: Container(
width: _circleHeight,
height: _circleHeight,
//color: Colors.red,
decoration: BoxDecoration(
border: Border.all(
color: lightTheme.primaryColor,
width: .0055 * _height,
),
borderRadius: BorderRadius.all(
Radius.circular(_circleHeight)),
color: Colors.transparent),
),
),
Padding(
padding: EdgeInsets.fromLTRB(
0.0, 0.0, .119 * _width, 0.0),
child: GestureDetector(
onTap:() => _OnboardingState.jumpForward(),
child: Text(
"NEXT",
style: lightTheme.primaryTextTheme.button,
)),)
],
)
],
),
),
)
],
),
),
),
);
}
}

Answer 1

If you want to do it that way just use a callback for your State method. You are trying to access a non-static method in a static way, plus, you're doing it wrong because even if the method was static, you wouldn't be accessing the active State and controller.
So, by using a callback, you want to pass it on the constructor of your class
class OnboardingPage extends StatelessWidget {
OnboardingPage({this.viewModel, this.onNextPressed});
final PageViewModel viewModel;
final VoidCallback onNextPressed;
(...)
Call it on your NEXT tap
GestureDetector(
onTap:() => onNextPressed(),
child: Text(
"NEXT",
style: lightTheme.primaryTextTheme.button,
)
)
And then passing the reference when adding the OnboardingPage to your widget tree in your build method
OnboardingPage(viewModel:pages[0],onNextPressed: jumpForward)