Use shared_ptr<Factory> as settings section id.

Telegram/SourceFiles/info/settings/info_settings_widget.cpp

@@ -45,7 +45,7 @@ Widget::Widget(
 , _self(controller->key().settingsSelf())
 , _type(controller->section().settingsType())
 , _inner([&] {
-	auto inner = _type()->create(this, controller->parentController());
+	auto inner = _type->create(this, controller->parentController());
 	if (inner->hasFlexibleTopBar()) {
 		auto filler = setInnerWidget(object_ptr<Ui::RpWidget>(this));
 		filler->resize(1, 1);

Telegram/SourceFiles/settings/cloud_password/settings_cloud_password_common.h

@@ -162,7 +162,7 @@ public:
 	}
 
 	[[nodiscard]] static Type Id() {
-		return &SectionMetaImplementation<SectionType>::Meta;
+		return SectionFactory<SectionType>::Instance();
 	}
 	[[nodiscard]] Type id() const final override {
 		return Id();

Telegram/SourceFiles/settings/settings_common.h

@@ -52,14 +52,16 @@ using Button = Ui::SettingsButton;
 
 class AbstractSection;
 
-struct SectionMeta {
+struct AbstractSectionFactory {
 	[[nodiscard]] virtual object_ptr<AbstractSection> create(
 		not_null<QWidget*> parent,
 		not_null<Window::SessionController*> controller) const = 0;
+
+	virtual ~AbstractSectionFactory() = default;
 };
 
 template <typename SectionType>
-struct SectionMetaImplementation : SectionMeta {
+struct SectionFactory : AbstractSectionFactory {
 	object_ptr<AbstractSection> create(
 		not_null<QWidget*> parent,
 		not_null<Window::SessionController*> controller
@@ -67,9 +69,9 @@ struct SectionMetaImplementation : SectionMeta {
 		return object_ptr<SectionType>(parent, controller);
 	}
 
-	[[nodiscard]] static not_null<SectionMeta*> Meta() {
+	[[nodiscard]] static const std::shared_ptr<SectionFactory> &Instance() {
-		static SectionMetaImplementation result;
+		static const auto result = std::make_shared<SectionFactory>();
-		return &result;
+		return result;
 	}
 };
 
@@ -120,7 +122,7 @@ public:
 	using AbstractSection::AbstractSection;
 
 	[[nodiscard]] static Type Id() {
-		return &SectionMetaImplementation<SectionType>::Meta;
+		return SectionFactory<SectionType>::Instance();
 	}
 	[[nodiscard]] Type id() const final override {
 		return Id();

Telegram/SourceFiles/settings/settings_local_passcode.cpp

@@ -330,7 +330,7 @@ public:
 	}
 
 	[[nodiscard]] static Type Id() {
-		return &SectionMetaImplementation<SectionType>::Meta;
+		return SectionFactory<SectionType>::Instance();
 	}
 	[[nodiscard]] Type id() const final override {
 		return Id();

Telegram/SourceFiles/settings/settings_notifications.cpp

@@ -171,7 +171,7 @@ void AddTypeButton(
 		st::settingsNotificationType,
 		{ icon });
 	button->setClickedCallback([=] {
-		showOther(NotificationsTypeId(type));
+		showOther(NotificationsType::Id(type));
 	});
 
 	const auto session = &controller->session();
@@ -290,7 +290,7 @@ void AddTypeButton(
 					tr::lng_notification_exceptions_view(),
 					[=] {
 						box->closeBox();
-						showOther(NotificationsTypeId(type));
+						showOther(NotificationsType::Id(type));
 					});
 			}));
 		}

Telegram/SourceFiles/settings/settings_notifications_type.cpp

@@ -36,6 +36,20 @@ namespace {
 
 using Notify = Data::DefaultNotify;
 
+struct Factory : AbstractSectionFactory {
+	explicit Factory(Notify type) : type(type) {
+	}
+
+	object_ptr<AbstractSection> create(
+		not_null<QWidget*> parent,
+		not_null<Window::SessionController*> controller
+	) const final override {
+		return object_ptr<NotificationsType>(parent, controller, type);
+	}
+
+	const Notify type = {};
+};
+
 class AddExceptionBoxController final
 	: public ChatsListBoxController
 	, public base::has_weak_ptr {
@@ -351,11 +365,6 @@ void ExceptionsController::sort() {
 	delegate()->peerListSortRows(predicate);
 }
 
-template <Notify kType>
-[[nodiscard]] Type Id() {
-	return &NotificationsTypeMetaImplementation<kType>::Meta;
-}
-
 [[nodiscard]] rpl::producer<QString> Title(Notify type) {
 	switch (type) {
 	case Notify::User: return tr::lng_notification_title_private_chats();
@@ -562,15 +571,6 @@ void SetupExceptions(
 
 } // namespace
 
-Type NotificationsTypeId(Notify type) {
-	switch (type) {
-	case Notify::User: return Id<Notify::User>();
-	case Notify::Group: return Id<Notify::Group>();
-	case Notify::Broadcast: return Id<Notify::Broadcast>();
-	}
-	Unexpected("Type in NotificationTypeId.");
-}
-
 NotificationsType::NotificationsType(
 	QWidget *parent,
 	not_null<Window::SessionController*> controller,
@@ -589,8 +589,8 @@ rpl::producer<QString> NotificationsType::title() {
 	Unexpected("Type in NotificationsType.");
 }
 
-Type NotificationsType::id() const {
+Type NotificationsType::Id(Notify type) {
-	return NotificationsTypeId(_type);
+	return std::make_shared<Factory>(type);
 }
 
 void NotificationsType::setupContent(

Telegram/SourceFiles/settings/settings_notifications_type.h

@@ -25,32 +25,19 @@ public:
 
 	[[nodiscard]] rpl::producer<QString> title() override;
 
-	[[nodiscard]] Type id() const final override;
+	[[nodiscard]] static Type Id(Data::DefaultNotify type);
+
+	[[nodiscard]] Type id() const final override {
+		return Id(_type);
+	}
 
 private:
 	void setupContent(not_null<Window::SessionController*> controller);
 
-	Data::DefaultNotify _type;
+	const Data::DefaultNotify _type;
 
 };
 
-template <Data::DefaultNotify kType>
-struct NotificationsTypeMetaImplementation : SectionMeta {
-	object_ptr<AbstractSection> create(
-		not_null<QWidget*> parent,
-		not_null<Window::SessionController*> controller
-	) const final override {
-		return object_ptr<NotificationsType>(parent, controller, kType);
-	}
-
-	[[nodiscard]] static not_null<SectionMeta*> Meta() {
-		static NotificationsTypeMetaImplementation result;
-		return &result;
-	}
-};
-
-[[nodiscard]] Type NotificationsTypeId(Data::DefaultNotify type);
-
 [[nodiscard]] bool NotificationsEnabledForType(
 	not_null<Main::Session*> session,
 	Data::DefaultNotify type);

Telegram/SourceFiles/settings/settings_type.h

@@ -9,7 +9,7 @@ https://github.com/telegramdesktop/tdesktop/blob/master/LEGAL
 
 namespace Settings {
 
-struct SectionMeta;
+struct AbstractSectionFactory;
-using Type = not_null<SectionMeta*>(*)();
+using Type = std::shared_ptr<AbstractSectionFactory>;
 
 } // namespace Settings