Text fields

A text widget binds two things the field owns: field.textController and field.focusNode. Toggle Lock below to see the difference enabled makes.

class _TextInput extends StatelessWidget {
  const _TextInput({required this.field, required this.label});

  final AdvancedTextFieldController<String> field;
  final String label;

  @override
  Widget build(BuildContext context) {
    return AdvancedFieldBuilder<String, String>(
      field: field,
      builder: (context, state, _) => Padding(
        padding: const EdgeInsets.symmetric(vertical: 6),
        child: TextFormField(
          controller: field.textController, // owned by the field
          focusNode: field.focusNode, // so onUnfocus and focus() work
          readOnly: state.readOnly, // blocks typing…
          enabled: !state.readOnly, // …and this makes it *look* frozen
          decoration: InputDecoration(labelText: label, errorText: state.error),
        ),
      ),
    );
  }
}

What the field does for you

• Two-way sync. User input flows into the field; setValue, reset, prefill and relations flow back into the visible text, with the caret kept on the same characters where possible.
• Read-only is enforced, not just styled. Text typed into a read-only field is reverted in the same turn — with readOnly: state.readOnly the keyboard never gets that far.
• Focus is tracked. Binding field.focusNode is what makes ValidationMode.onUnfocus fire and what lets field.focus() jump to this input. See Focus.

Read-only, visibly

TextField.readOnly blocks typing but keeps the enabled styling, so pass enabled: !state.readOnly too when a frozen field should look frozen. Widgets with a nullable callback — switches, checkboxes, dropdowns, sliders — grey out on their own once the callback is null.