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avoid-missing-controller

Group: Correctness
Path: lint/correctness/avoid-missing-controller
Default: Off, opt in
Origin: Falcon
Domain: flutter
Rule: 85 of 512

flutter

Require Flutter text fields to expose their updated value.

TextField, TextFormField, CupertinoTextField, and EditableText need a non-null controller or a value callback supported by that API. Explicit readOnly:true and enabled:false fields are display-only and skipped. Dynamic expressions are accepted; unrelated classes and shadowed constructors are ignored.

Invalid

example.dartdart

import 'package:flutter/material.dart';
import 'package:flutter/material.dart' as f;

void fields() {
  TextField();
  TextFormField();
  f.CupertinoTextField.borderless();
  new EditableText(controller: null);
  TextField(controller: null, onChanged: null);
  TextFormField(onSaved: null);
}

Provide a controller or a callback that receives the updated field value.

4void fields() {

5 TextField();

∙

Provide a controller or a callback that receives the updated field value.

5 TextField();

6 TextFormField();

∙

Provide a controller or a callback that receives the updated field value.

6 TextFormField();

7 f.CupertinoTextField.borderless();

∙

Provide a controller or a callback that receives the updated field value.

7 f.CupertinoTextField.borderless();

8 new EditableText(controller: null);

∙

Provide a controller or a callback that receives the updated field value.

8 new EditableText(controller: null);

9 TextField(controller: null, onChanged: null);

∙

Provide a controller or a callback that receives the updated field value.

9 TextField(controller: null, onChanged: null);

10 TextFormField(onSaved: null);

∙

Valid

example.dartdart

import 'package:flutter/material.dart';
import 'package:flutter/material.dart' as f;

void fields(Object? controller, Function callback) {
  TextField(controller: controller);
  TextFormField(onChanged: callback);
  f.CupertinoTextField.borderless(onSubmitted: callback);
  EditableText(onChanged: callback);
  TextFormField(onSaved: callback);
  TextFormField(onFieldSubmitted: callback);
  TextField(controller: TextEditingController());
  TextField(readOnly: true);
  TextFormField(enabled: false);
  CupertinoTextField.borderless(readOnly: true);
  EditableText(readOnly: true);
}
void shadow(dynamic TextField) { TextField(); }

Configure avoid-missing-controller

Set its severity in falcon.json. See the configuration guide.

falcon.jsonjson

{
  "linter": {
    "rules": {
      "correctness": {
        "avoid-missing-controller": "error"
      }
    }
  }
}

Or silence one occurrence with a suppression comment; the reason is required.

example.dartdart

// falcon-ignore lint/correctness/avoid-missing-controller: <reason>

avoid-missing-enum-constant-in-map
Require enum-keyed map literals to include every declared enum value.
avoid-missing-interpolationrecommended
Flags missing interpolation around visible String variables or member accesses and calls.
avoid-misused-hooksrecommendedflutter_hooks
Flags confirmed Flutter hooks called directly in non-hook Flutter widget builds.
avoid-mounted-in-setstateflutter
Check mounted before invoking Flutter State.setState, never inside its callback.
avoid-mutable-equatable-subclass-fieldsrecommendedequatable
Flags mutable instance fields on subclasses inheriting Equatable equality.
avoid-mutable-global-variablesavoid_mutable_global_variables
Disallow mutable top-level variables.
avoid-nested-futures
Avoid Future<Future<T>>, FutureOr<Future<T>>, and other directly nested future wrappers.
avoid-nested-streams-and-futures
Avoid directly nesting SDK streams and futures: Stream<Future<T>> and Future<Stream<T>> complicate consumption.