Shown Error: NoSuchMethodError: The getter 'text' was called on null.
The getter 'text was called on null.
Receiver: null
Tried calling: text

How to create getter that get each controller value from the constructor? so that I can call it in the TextFormField

import 'package:flutter/material.dart';
class CustomTextFieldForm extends StatefulWidget {
  final TextEditingController controller;
  final String hintText;
  final String errorMessage;

  const CustomTextFieldForm({
    Key? key,
    required this.controller,
    required this.hintText,
    required this.errorMessage,
    required Null Function(dynamic text) onChanged,
  }) : super(key: key);
  @override
  _CustomTextFieldFormState createState() => _CustomTextFieldFormState();
}

class _CustomTextFieldFormState extends State<CustomTextFieldForm> {
  get controller => null;

  get errorMessage => null;

  get hintText => null;

  


  @override
  Widget build(BuildContext context) {
    return TextFormField(

      controller: controller,
      validator: (String? value) {
        if (value!.isEmpty) {
          return errorMessage;
        }
        return null;
      },
      decoration: InputDecoration(
          hintText: hintText,
          hintStyle: const TextStyle(
            fontSize: 18,
            fontWeight: FontWeight.w200,
          ),
          errorStyle: TextStyle(height: 0),
          suffixIcon: controller.text.length > 0 ? IconButton(
              onPressed: () {
                controller.clear();
                setState(() {});
              },
              icon: Icon(Icons.cancel, color: Colors.grey))
              : null
      ),
    );
  }

}

CodePudding user response：

Use widget.variable_name to access variable from statefulWidget class to state class.

TextEditingController get controller => widget.controller;

String get errorMessage => widget.hintText;

String get hintText => widget.errorMessage;

CodePudding user response：

you're trying to get the text from the widget constructor, which you set to a return of type Null, so normally it will throw a null.

what you need to do to make it work :

change this :

    required Null Function(dynamic text) onChanged,

with this

    required this.onChanged,

then declare that onChanged function with other variables

  final TextEditingController controller;
  final String hintText;
  final String errorMessage;
  final Function(dynamic) onChanged;

Hope it helps.