Reduce boilerplate code in Change Notifier-based hooks

Author: yelliver

packages/flutter_hooks/lib/src/change_notifier.dart

@@ -0,0 +1,36 @@
+part of 'hooks.dart';
+
+T _useChangeNotifier<T extends ChangeNotifier>(
+  ValueGetter<T> builder,
+  List<Object?>? keys,
+) {
+  return use(_ChangeNotifierHook(builder, keys));
+}
+
+class _ChangeNotifierHook<T extends ChangeNotifier> extends Hook<T> {
+  const _ChangeNotifierHook(
+    this.builder,
+    List<Object?>? keys,
+  ) : super(keys: keys);
+
+  final ValueGetter<T> builder;
+
+  @override
+  HookState<T, Hook<T>> createState() => _ChangeNotifierHookState<T>(builder);
+}
+
+class _ChangeNotifierHookState<T extends ChangeNotifier>
+    extends HookState<T, _ChangeNotifierHook<T>> {
+  _ChangeNotifierHookState(ValueGetter<T> builder) : controller = builder();
+
+  final T controller;
+
+  @override
+  String get debugLabel => 'use${controller.runtimeType}';
+
+  @override
+  T build(BuildContext context) => controller;
+
+  @override
+  void dispose() => controller.dispose();
+}

packages/flutter_hooks/lib/src/draggable_scrollable_controller.dart

@@ -7,28 +7,5 @@ part of 'hooks.dart';
 DraggableScrollableController useDraggableScrollableController({
   List<Object?>? keys,
 }) {
-  return use(_DraggableScrollableControllerHook(keys: keys));
-}
-
-class _DraggableScrollableControllerHook
-    extends Hook<DraggableScrollableController> {
-  const _DraggableScrollableControllerHook({super.keys});
-
-  @override
-  HookState<DraggableScrollableController, Hook<DraggableScrollableController>>
-      createState() => _DraggableScrollableControllerHookState();
-}
-
-class _DraggableScrollableControllerHookState extends HookState<
-    DraggableScrollableController, _DraggableScrollableControllerHook> {
-  final controller = DraggableScrollableController();
-
-  @override
-  String get debugLabel => 'useDraggableScrollableController';
-
-  @override
-  DraggableScrollableController build(BuildContext context) => controller;
-
-  @override
-  void dispose() => controller.dispose();
+  return _useChangeNotifier(DraggableScrollableController.new, keys);
 }

packages/flutter_hooks/lib/src/fixed_extent_scroll_controller.dart

@@ -10,48 +10,14 @@ FixedExtentScrollController useFixedExtentScrollController({
   ScrollControllerCallback? onDetach,
   List<Object?>? keys,
 }) {
-  return use(
-    _FixedExtentScrollControllerHook(
-      initialItem: initialItem,
-      onAttach: onAttach,
-      onDetach: onDetach,
-      keys: keys,
-    ),
+  return _useChangeNotifier(
+    () {
+      return FixedExtentScrollController(
+        initialItem: initialItem,
+        onAttach: onAttach,
+        onDetach: onDetach,
+      );
+    },
+    keys,
   );
 }
-
-class _FixedExtentScrollControllerHook
-    extends Hook<FixedExtentScrollController> {
-  const _FixedExtentScrollControllerHook({
-    required this.initialItem,
-    this.onAttach,
-    this.onDetach,
-    super.keys,
-  });
-
-  final int initialItem;
-  final ScrollControllerCallback? onAttach;
-  final ScrollControllerCallback? onDetach;
-
-  @override
-  HookState<FixedExtentScrollController, Hook<FixedExtentScrollController>>
-      createState() => _FixedExtentScrollControllerHookState();
-}
-
-class _FixedExtentScrollControllerHookState extends HookState<
-    FixedExtentScrollController, _FixedExtentScrollControllerHook> {
-  late final controller = FixedExtentScrollController(
-    initialItem: hook.initialItem,
-    onAttach: hook.onAttach,
-    onDetach: hook.onDetach,
-  );
-
-  @override
-  FixedExtentScrollController build(BuildContext context) => controller;
-
-  @override
-  void dispose() => controller.dispose();
-
-  @override
-  String get debugLabel => 'useFixedExtentScrollController';
-}

packages/flutter_hooks/lib/src/hooks.dart

@@ -17,6 +17,7 @@ import 'framework.dart';
 
 part 'animation.dart';
 part 'async.dart';
+part 'change_notifier.dart';
 part 'draggable_scrollable_controller.dart';
 part 'expansion_tile_controller.dart';
 part 'fixed_extent_scroll_controller.dart';

packages/flutter_hooks/lib/src/page_controller.dart

@@ -12,55 +12,14 @@ PageController usePageController({
   ScrollControllerCallback? onDetach,
   List<Object?>? keys,
 }) {
-  return use(
-    _PageControllerHook(
+  return _useChangeNotifier(
+    () => PageController(
       initialPage: initialPage,
       keepPage: keepPage,
       viewportFraction: viewportFraction,
       onAttach: onAttach,
       onDetach: onDetach,
-      keys: keys,
     ),
+    keys,
   );
 }
-
-class _PageControllerHook extends Hook<PageController> {
-  const _PageControllerHook({
-    required this.initialPage,
-    required this.keepPage,
-    required this.viewportFraction,
-    this.onAttach,
-    this.onDetach,
-    List<Object?>? keys,
-  }) : super(keys: keys);
-
-  final int initialPage;
-  final bool keepPage;
-  final double viewportFraction;
-  final ScrollControllerCallback? onAttach;
-  final ScrollControllerCallback? onDetach;
-
-  @override
-  HookState<PageController, Hook<PageController>> createState() =>
-      _PageControllerHookState();
-}
-
-class _PageControllerHookState
-    extends HookState<PageController, _PageControllerHook> {
-  late final controller = PageController(
-    initialPage: hook.initialPage,
-    keepPage: hook.keepPage,
-    viewportFraction: hook.viewportFraction,
-    onAttach: hook.onAttach,
-    onDetach: hook.onDetach,
-  );
-
-  @override
-  PageController build(BuildContext context) => controller;
-
-  @override
-  void dispose() => controller.dispose();
-
-  @override
-  String get debugLabel => 'usePageController';
-}

packages/flutter_hooks/lib/src/scroll_controller.dart

@@ -12,55 +12,14 @@ ScrollController useScrollController({
   ScrollControllerCallback? onDetach,
   List<Object?>? keys,
 }) {
-  return use(
-    _ScrollControllerHook(
+  return _useChangeNotifier(
+    () => ScrollController(
       initialScrollOffset: initialScrollOffset,
       keepScrollOffset: keepScrollOffset,
       debugLabel: debugLabel,
       onAttach: onAttach,
       onDetach: onDetach,
-      keys: keys,
     ),
+    keys,
   );
 }
-
-class _ScrollControllerHook extends Hook<ScrollController> {
-  const _ScrollControllerHook({
-    required this.initialScrollOffset,
-    required this.keepScrollOffset,
-    this.debugLabel,
-    this.onAttach,
-    this.onDetach,
-    List<Object?>? keys,
-  }) : super(keys: keys);
-
-  final double initialScrollOffset;
-  final bool keepScrollOffset;
-  final String? debugLabel;
-  final ScrollControllerCallback? onAttach;
-  final ScrollControllerCallback? onDetach;
-
-  @override
-  HookState<ScrollController, Hook<ScrollController>> createState() =>
-      _ScrollControllerHookState();
-}
-
-class _ScrollControllerHookState
-    extends HookState<ScrollController, _ScrollControllerHook> {
-  late final controller = ScrollController(
-    initialScrollOffset: hook.initialScrollOffset,
-    keepScrollOffset: hook.keepScrollOffset,
-    debugLabel: hook.debugLabel,
-    onAttach: hook.onAttach,
-    onDetach: hook.onDetach,
-  );
-
-  @override
-  ScrollController build(BuildContext context) => controller;
-
-  @override
-  void dispose() => controller.dispose();
-
-  @override
-  String get debugLabel => 'useScrollController';
-}

packages/flutter_hooks/lib/src/search_controller.dart

@@ -5,27 +5,5 @@ part of 'hooks.dart';
 /// See also:
 /// - [SearchController]
 SearchController useSearchController({List<Object?>? keys}) {
-  return use(_SearchControllerHook(keys: keys));
-}
-
-class _SearchControllerHook extends Hook<SearchController> {
-  const _SearchControllerHook({List<Object?>? keys}) : super(keys: keys);
-
-  @override
-  HookState<SearchController, Hook<SearchController>> createState() =>
-      _SearchControllerHookState();
-}
-
-class _SearchControllerHookState
-    extends HookState<SearchController, _SearchControllerHook> {
-  final controller = SearchController();
-
-  @override
-  String get debugLabel => 'useSearchController';
-
-  @override
-  SearchController build(BuildContext context) => controller;
-
-  @override
-  void dispose() => controller.dispose();
+  return _useChangeNotifier(SearchController.new, keys);
 }

packages/flutter_hooks/lib/src/tab_controller.dart

@@ -11,48 +11,13 @@ TabController useTabController({
   List<Object?>? keys,
 }) {
   vsync ??= useSingleTickerProvider(keys: keys);
-
-  return use(
-    _TabControllerHook(
-      vsync: vsync,
+  final localVsync = vsync;
+  return _useChangeNotifier(
+    () => TabController(
+      vsync: localVsync,
       length: initialLength,
       initialIndex: initialIndex,
-      keys: keys,
     ),
+    keys,
   );
 }
-
-class _TabControllerHook extends Hook<TabController> {
-  const _TabControllerHook({
-    required this.length,
-    required this.vsync,
-    required this.initialIndex,
-    List<Object?>? keys,
-  }) : super(keys: keys);
-
-  final int length;
-  final TickerProvider vsync;
-  final int initialIndex;
-
-  @override
-  HookState<TabController, Hook<TabController>> createState() =>
-      _TabControllerHookState();
-}
-
-class _TabControllerHookState
-    extends HookState<TabController, _TabControllerHook> {
-  late final controller = TabController(
-    length: hook.length,
-    initialIndex: hook.initialIndex,
-    vsync: hook.vsync,
-  );
-
-  @override
-  TabController build(BuildContext context) => controller;
-
-  @override
-  void dispose() => controller.dispose();
-
-  @override
-  String get debugLabel => 'useTabController';
-}

packages/flutter_hooks/lib/src/text_controller.dart

@@ -8,7 +8,7 @@ class _TextEditingControllerHookCreator {
   /// The [text] parameter can be used to set the initial value of the
   /// controller.
   TextEditingController call({String? text, List<Object?>? keys}) {
-    return use(_TextEditingControllerHook(text, keys));
+    return _useChangeNotifier(() => TextEditingController(text: text), keys);
   }
 
   /// Creates a [TextEditingController] from the initial [value] that will
@@ -17,7 +17,10 @@ class _TextEditingControllerHookCreator {
     TextEditingValue value, [
     List<Object?>? keys,
   ]) {
-    return use(_TextEditingControllerHook.fromValue(value, keys));
+    return _useChangeNotifier(
+      () => TextEditingController.fromValue(value),
+      keys,
+    );
   }
 }
 
@@ -54,41 +57,3 @@ class _TextEditingControllerHookCreator {
 /// See also:
 /// - [TextEditingController], which this hook creates.
 const useTextEditingController = _TextEditingControllerHookCreator();
-
-class _TextEditingControllerHook extends Hook<TextEditingController> {
-  const _TextEditingControllerHook(
-    this.initialText, [
-    List<Object?>? keys,
-  ])  : initialValue = null,
-        super(keys: keys);
-
-  const _TextEditingControllerHook.fromValue(
-    TextEditingValue this.initialValue, [
-    List<Object?>? keys,
-  ])  : initialText = null,
-        super(keys: keys);
-
-  final String? initialText;
-  final TextEditingValue? initialValue;
-
-  @override
-  _TextEditingControllerHookState createState() {
-    return _TextEditingControllerHookState();
-  }
-}
-
-class _TextEditingControllerHookState
-    extends HookState<TextEditingController, _TextEditingControllerHook> {
-  late final _controller = hook.initialValue != null
-      ? TextEditingController.fromValue(hook.initialValue)
-      : TextEditingController(text: hook.initialText);
-
-  @override
-  TextEditingController build(BuildContext context) => _controller;
-
-  @override
-  void dispose() => _controller.dispose();
-
-  @override
-  String get debugLabel => 'useTextEditingController';
-}