How to use a method in a Stateful Widget from another Widget

Question

So i have this toggle() method in the Stateful SideBar class

class SideBar extends StatefulWidget { const SideBar({super.key}); @override State<SideBar> createState() => _SideBarState(); } class _SideBarState extends State<SideBar> with SingleTickerProviderStateMixin{ void toggle() { if (_controller.isCompleted) { _controller.reverse(); } else {_controller.forward();} } }

and i want to use it in

class SideBarWidget extends StatelessWidget { SideBarWidget({Key? key}) : super(key: key); final SideBar sideBarWidget = SideBar(...); void toggle() { // here i want to use the toggle() method } @override Widget build(BuildContext context) { return sideBarWidget; } }

I cannot use sideBarWidget.toggle() I also cannot pass it as a parameter becasue the _controller is in the SideBar() widget

Boolean_Type · Accepted Answer · 2023-01-27 08:22:03Z

1

There are many ways, but the most common and simple is to create an instance of the SideBar class inside the SideBarWidget class, for example:

var side = SideBar();

And then you can access the toggle() method like this: side.toggle().

edited Jan 27, 2023 at 8:22

Boolean_Type

1,3423 gold badges14 silver badges44 bronze badges

answered Jan 24, 2023 at 10:35

Fotis Psarris

12012 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Pulina Hansana Over a year ago

I've tried that as you see in the SideBarWidget class but I cant access the toggle method..

Fotis Psarris Over a year ago

I need more of your code and the error your IDE shows.

Hitarth Chhunchha · Accepted Answer · 2023-01-24 11:28:03Z

remove underscore from SideBarState

to use method of SideBarState in SideBarWidget use: SideBarState().toggle();

**screen1.dart** class ParentWidget extends StatefulWidget { const ParentWidget({Key? key}) : super(key: key); @override State<ParentWidget> createState() => ParentWidgetState(); } class ParentWidgetState extends State<ParentWidget> { void printData() { print("parent"); } @override Widget build(BuildContext context) { return const Placeholder(); } } **screen2.dart** import 'package:demo/screen_1.dart'; import 'package:flutter/material.dart'; class ChildWidget extends StatelessWidget { const ChildWidget({Key? key}) : super(key: key); @override Widget build(BuildContext context) { ParentWidgetState().printData(); return const Placeholder(); } }

Ivo · Accepted Answer · 2023-01-24 10:42:18Z

One way is to give the SideBar a GlobalKey and get the state from the key afterwards. An example:

class SideBar extends StatefulWidget { const SideBar({super.key}); @override State<SideBar> createState() => SideBarState(); } class SideBarState extends State<SideBar> with SingleTickerProviderStateMixin{ @override Widget build(BuildContext context) { return Container(); } void toggle() { print('toggle'); } } class SideBarWidget extends StatelessWidget { SideBarWidget({Key? key}) : super(key: key); final GlobalKey<SideBarState> sideBarKey = GlobalKey(); late final SideBar sideBarWidget = SideBar(key: sideBarKey); void toggle() { sideBarKey.currentState?.toggle(); } @override Widget build(BuildContext context) { return Column( children: [ TextButton(onPressed: toggle, child: const Text('click')), sideBarWidget, ], ); } }

Collectives™ on Stack Overflow

How to use a method in a Stateful Widget from another Widget

3 Answers 3

2 Comments

Comments

Comments

Hot Network Questions

Collectives™ on Stack Overflow

3 Answers 3

2 Comments

Comments

Comments

Related