CODEWITHSUNDEEP
flutterdart
Rubén Cantón
Rubén Cantón

Reputation: 124

Why my TextFormField value doesn't change here?

Well it's probably a very simple question but I'm starting and I'm not able to find too much documentation about flutter...

import 'package:flutter/material.dart';

class AutoChangeField extends StatefulWidget {
  @override
  _AutoChangeFieldState createState() => _AutoChangeFieldState();
}

class _AutoChangeFieldState extends State<AutoChangeField> {

  Color _color = Colors.black;
  String _newValue = 'write something';

  @override
  Widget build(BuildContext context) {
    return TextFormField(
      initialValue: _newValue,
      cursorColor: _color,
      onChanged: (val){
        setState(() {
          _newValue = "It changed!";
          _color = Colors.red;
        });
      },
    );
  }
}

Just the cursorColor swaps to red properly when you write something at the TextFormField, but the value of it does not. Value keeps being "write something + (what u writed)" instead of "It changed!". :(

Thanks you so much.

Upvotes: 0

Views: 1052

Answers (2)

Josteve Adekanbi
Josteve Adekanbi

Reputation: 12713

You should use a TextEditingController and set the initialValue of the TextEditingController to "Write something"

Like this

class AutoChangeField extends StatefulWidget {
  @override
  _AutoChangeFieldState createState() => _AutoChangeFieldState();
}

class _AutoChangeFieldState extends State<AutoChangeField> {

  Color _color = Colors.black;
  TextEditingController controller = TextEditingController(text: "Write something");

  @override
  Widget build(BuildContext context) {
    return TextFormField(
      controller: controller,
      cursorColor: _color,
      onChanged: (val){
        print(val);
        controller.text = "It changed!";
        setState(() {
          _color = Colors.red;
        });
      },
    );
  }
}

NOTE: You cannot use the controller and initialValue at the same time.

Upvotes: 2

Sukhi
Sukhi

Reputation: 14205

You need to use 'controller' proeprty.

Define a controller like below :

TextEditingController myController = new TextEditingController();

Assign it to the TextFormField as :

TextFormField(
      controller: myController,

Now, assign a new value as :

myController.text = "its changed";

Upvotes: 2

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