Checkbox form validation

Question

How can I validate a checkbox in a Flutter Form? Every other validation works fine, but the checkbox doesn\'t show an Error. Here is my code:

FormFi         


        

Answer 1

The above answer is correct, however, if you want to display an error message that is more consistent with the default layout of a TextFormField widget error message, then wrap the Text widget in a Padding widget, and give it the hex colour #e53935.

Note: You may need to adjust the left padding to fit the CheckboxListTile widget is also wrapped in a Padding widget.

Check the code below:

    bool _termsChecked = false;
    CheckboxListTile(
              activeColor: Theme.of(context).accentColor,
              title: Text('I agree to'),
              value: _termsChecked,
              onChanged: (bool value) => setState(() => _termsChecked = value),
              subtitle: !_termsChecked
                ? Padding(
                    padding: EdgeInsets.fromLTRB(12.0, 0, 0, 0), 
                    child: Text('Required field', style: TextStyle(color: Color(0xFFe53935), fontSize: 12),),)
                : null,
            ),