I am getting error while trying to pass bool value to the TaskCheckbox() method. I am new to flutter and any help would be much appreciated

class _TaskTileState extends State<TaskTile> {
          bool? isChecked = false;
        
          @override
          Widget build(BuildContext context) {
            return const ListTile(
              title: Text('This is a task'),
              trailing: TaskCheckbox(isChecked),
            );
          }
    
    }
    
    class TaskCheckbox extends StatelessWidget {
      final bool? checkboxState;
      const TaskCheckbox(this.checkboxState, {Key? key}) : super(key: key);
    
      @override
      Widget build(BuildContext context) {
        return Checkbox(
          value: checkboxState,
          onChanged: (newValue) {},
        );
      }
    }

CodePudding user response：

You need to remove const before ListTile because the value will get on runtime.

  @override
  Widget build(BuildContext context) {
    return ListTile(
      title: Text('This is a task'),
      trailing: TaskCheckbox(isChecked),
    );
  }

const keyword used to make a variable to store a compile time constant value. Compile time constant value is a value which will be constant while compiling , ref

CodePudding user response：

You need to use Stateful Class widget for the build checkbox because we need to use setState for changing value inside the checkbox.

Use this code. This work fine for me:

class TaskTileState extends StatefulWidget {
  @override
  _TaskTileState createState() => _TaskTileState();
}

class _TaskTileState extends State<MyHomePage> {
  bool? isChecked = true;

  @override
  Widget build(BuildContext context) {
    return ListTile(
      title: Text('This is a task'),
      trailing: TaskCheckbox(isChecked),
    );
  }
}


class TaskCheckbox extends StatefulWidget {
  final bool? checkboxState;
  const TaskCheckbox(this.checkboxState, {Key? key}) : super(key: key);

  @override
  State<TaskCheckbox> createState() => _TaskCheckboxState();
}

class _TaskCheckboxState extends State<TaskCheckbox> {
  bool? isChecked;
  
  @override
  void initState() {
    isChecked = widget.checkboxState;
  }

  @override
  Widget build(BuildContext context) {
    Color getColor(Set<MaterialState> states) {
      const Set<MaterialState> interactiveStates = <MaterialState>{
        MaterialState.pressed,
        MaterialState.hovered,
        MaterialState.focused,
      };
      if (states.any(interactiveStates.contains)) {
        return Colors.blue;
      }
      return Colors.red;
    }

    return Checkbox(
      checkColor: Colors.black,
      fillColor: MaterialStateProperty.resolveWith(getColor),
      value: isChecked,
      onChanged: (bool? value) {
        setState(() {
          isChecked = value!;
        });
      },
    );
  }
}

Related from @Yeasin Sheikh's answer, you do have to remove the const in the ListView