I want to make a clickable iconButton with a different boolean value init.

get the IconButton code :

Row(
 children: [
  CheckIcon(isCheck: true,),
  CheckIcon(isCheck: false,),
  CheckIcon(isCheck: true,),
 ],
),

IconButton Code :

import 'package:flutter/material.dart';

class CheckIcon extends StatefulWidget {
  static bool? isCheck;

  //the error is hire
  const CheckIcon({
    Key? key,
    // I can't initialize the static boolean in constructor
  }) : super(key: key);

  @override
  State<CheckIcon> createState() => _CheckIconState();
}

class _CheckIconState extends State<CheckIcon> {
  @override
  Widget build(BuildContext context) {
    return IconButton(
      splashRadius: 18.0,
      icon: Icon(
        CheckIcon.isCheck!
            ? Icons.check_circle_rounded
            : Icons.check_circle_outline_rounded,
        color: Colors.lightBlue,
        size: 20,
      ),
      onPressed: () {
        setState(() {
          CheckIcon.isCheck = !CheckIcon.isCheck!;
        });
      },
    );
  }
}

How to initialize the static boolean in the constructor stateful widget in flutter?

I hope you have the idea to share, cheers... thanks

CodePudding user response：

Why use static? Static field is shared across all instances, you won't have different states.

Instead use State field and change it in setState method:

class CheckIcon extends StatefulWidget {
  final bool isCheck;

  const CheckIcon({
    Key? key,
    required this.isCheck, // here we set first value
  }) : super(key: key);

  @override
  State<CheckIcon> createState() => _CheckIconState();
}

class _CheckIconState extends State<CheckIcon> {
  late bool checked = widget.isCheck; // here we set first value and then change it in setState

  @override
  Widget build(BuildContext context) {
    return IconButton(
      splashRadius: 18.0,
      icon: Icon(
        checked
            ? Icons.check_circle_rounded
            : Icons.check_circle_outline_rounded,
        color: Colors.lightBlue,
        size: 20,
      ),
      onPressed: () {
        setState(() {
          checked = !checked;
        });
      },
    );
  }
}

CodePudding user response：

Youu can't pass the static in construction please refer to the below doc.

https://dart.dev/tools/diagnostic-messages?utm_source=dartdev&utm_medium=redir&utm_id=diagcode&utm_content=initializer_for_static_field#initializer_for_static_field

instead you can use this if it's okay in your case.

 // ignore: must_be_immutable
 class CheckIcon extends StatefulWidget {
   bool isCheck;
 
   CheckIcon({
     Key? key,
     required this.isCheck,
   }) : super(key: key);
 
   @override
   State<CheckIcon> createState() => _CheckIconState();
 }
 
 class _CheckIconState extends State<CheckIcon> {
   @override
   Widget build(BuildContext context) {
     return IconButton(
       splashRadius: 18.0,
       icon: Icon(
         widget.isCheck ? Icons.check_circle_rounded : Icons.check_circle_outline_rounded,
         color: Colors.lightBlue,
         size: 20,
       ),
       onPressed: () {
         setState(() {
           widget.isCheck = !widget.isCheck;
         });
       },
     );
   }
 }

CodePudding user response：

You cant use a static variable in constructor. You can do it like the following

class CheckIcon extends StatefulWidget {
  final bool? isCheck;


  const CheckIcon({
    Key? key,
required this.isCheck
  }) : super(key: key);

  @override
  State<CheckIcon> createState() => _CheckIconState();
}

class _CheckIconState extends State<CheckIcon> {
  @override
  Widget build(BuildContext context) {
    return IconButton(
      splashRadius: 18.0,
      icon: Icon(
        CheckIcon.isCheck!
            ? Icons.check_circle_rounded
            : Icons.check_circle_outline_rounded,
        color: Colors.lightBlue,
        size: 20,
      ),
      onPressed: () {
        setState(() {
          widget.isCheck = !widget.isCheck!;
        });
      },
    );
  }
}