- Qt 6.12
- Qt Location
- C++ Classes
- QPlaceManagerEngine
- Qt 6.12.0 Reference Documentation

# QPlaceManagerEngine Class

The QPlaceManagerEngine class provides an interface for implementers of QGeoServiceProvider plugins who want to provide access to place functionality. More...

Header: | `#include <QPlaceManagerEngine>`
qmake: | `QT += location`
Inherits: | QObject

- List of all members, including inherited members

## Public Functions

| QPlaceManagerEngine(const QVariantMap &parameters, QObject *parent = nullptr)
virtual | ~QPlaceManagerEngine()
virtual QPlaceCategory | category(const QString &categoryId) const
virtual QList<QPlaceCategory> | childCategories(const QString &parentId) const
virtual QStringList | childCategoryIds(const QString &categoryId) const
virtual QPlace | compatiblePlace(const QPlace &original) const
virtual QUrl | constructIconUrl(const QPlaceIcon &icon, const QSize &size) const
virtual QPlaceContentReply * | getPlaceContent(const QPlaceContentRequest &request)
virtual QPlaceDetailsReply * | getPlaceDetails(const QString &placeId)
virtual QPlaceReply * | initializeCategories()
virtual QList<QLocale> | locales() const
QString | managerName() const
int | managerVersion() const
virtual QPlaceMatchReply * | matchingPlaces(const QPlaceMatchRequest &request)
virtual QString | parentCategoryId(const QString &categoryId) const
virtual QPlaceIdReply * | removeCategory(const QString &categoryId)
virtual QPlaceIdReply * | removePlace(const QString &placeId)
virtual QPlaceIdReply * | saveCategory(const QPlaceCategory &category, const QString &parentId)
virtual QPlaceIdReply * | savePlace(const QPlace &place)
virtual QPlaceSearchReply * | search(const QPlaceSearchRequest &request)
virtual QPlaceSearchSuggestionReply * | searchSuggestions(const QPlaceSearchRequest &request)
virtual void | setLocales(const QList<QLocale> &locales)

## Signals

void | categoryAdded(const QPlaceCategory &category, const QString &parentId)
void | categoryRemoved(const QString &categoryId, const QString &parentId)
void | categoryUpdated(const QPlaceCategory &category, const QString &parentId)
void | dataChanged()
void | errorOccurred(QPlaceReply *reply, QPlaceReply::Error error, const QString &errorString = QString())
void | finished(QPlaceReply *reply)
void | placeAdded(const QString &placeId)
void | placeRemoved(const QString &placeId)
void | placeUpdated(const QString &placeId)

## Protected Functions

QPlaceManager * | manager() const

## Detailed Description

Note: There are no source or binary compatibility guarantees for the backend classes. The API is only guaranteed to work with the Qt version it was developed against. API changes will however only be made in minor releases. (6.6, 6.7, and so on.)

Application developers need not concern themselves with the QPlaceManagerEngine. Backend implementers however will need to derive from QPlaceManagerEngine and provide implementations for the abstract virtual functions.

For more information on writing a backend see the Places Backend documentation.

See also QPlaceManager.

## Member Function Documentation

### `[explicit]` QPlaceManagerEngine::QPlaceManagerEngine(const QVariantMap &parameters, QObject *parent = nullptr)

Constructs a new engine with the specified parent, using parameters to pass any implementation specific data to the engine.

### `[virtual noexcept]` QPlaceManagerEngine::~QPlaceManagerEngine()

Destroys this engine.

### `[virtual]` QPlaceCategory QPlaceManagerEngine::category(const QString &categoryId) const

Returns the category corresponding to the given categoryId.

### `[signal]` void QPlaceManagerEngine::categoryAdded(const QPlaceCategory &category, const QString &parentId)

This signal is emitted if a category has been added to the manager engine's datastore. The parent of the category is specified by parentId.

This signal is only emitted by manager engines that support the QPlaceManager::NotificationsFeature.

See also dataChanged().

### `[signal]` void QPlaceManagerEngine::categoryRemoved(const QString &categoryId, const QString &parentId)

This signal is emitted when the category corresponding to categoryId has been removed from the manager engine's datastore. The parent of the removed category is specified by parentId.

This signal is only emitted by manager engines that support the QPlaceManager::NotificationsFeature.

See also dataChanged().

### `[signal]` void QPlaceManagerEngine::categoryUpdated(const QPlaceCategory &category, const QString &parentId)

This signal is emitted if a category has been modified in the manager engine's datastore. The parent of the modified category is specified by parentId.

This signal is only emitted by manager engines that support the QPlaceManager::NotificationsFeature.

See also dataChanged().

### `[virtual]` QList<QPlaceCategory> QPlaceManagerEngine::childCategories(const QString &parentId) const

Returns a list of categories that are children of the category corresponding to parentId. If parentId is empty, all the top level categories are returned.

### `[virtual]` QStringList QPlaceManagerEngine::childCategoryIds(const QString &categoryId) const

Returns the child category identifiers of the category corresponding to categoryId. If categoryId is empty then all top level category identifiers are returned.

### `[virtual]` QPlace QPlaceManagerEngine::compatiblePlace(const QPlace &original) const

Returns a pruned or modified version of the original place which is suitable to be saved by the manager engine.

Only place details that are supported by this manager is present in the modified version. Manager specific data such as the place id, is not copied over from the original.

### `[virtual]` QUrl QPlaceManagerEngine::constructIconUrl(const QPlaceIcon &icon, const QSize &size) const

QUrl QPlaceManagerEngine::constructIconUrl(const QPlaceIcon &icon, const QSize &size)

Constructs an icon url from a given icon, size. The URL of the icon image that most closely matches the given parameters is returned.

### `[signal]` void QPlaceManagerEngine::dataChanged()

*

This signal is emitted by the engine if there are large scale changes to its underlying datastore and the engine considers these changes radical enough to require clients to reload all data.

If the signal is emitted, no other signals will be emitted for the associated changes.

### `[signal]` void QPlaceManagerEngine::errorOccurred(QPlaceReply *reply, QPlaceReply::Error error, const QString &errorString = QString())

This signal is emitted when an error has been detected in the processing of reply. The QPlaceManager::finished() signal will probably follow.

The error will be described by the error code error. If errorString is not empty it will contain a textual description of the error meant for developers and not end users.

This signal and QPlaceReply::errorOccurred() will be emitted at the same time.

Note: Do not delete the reply object in the slot connected to this signal. Use deleteLater() instead.

### `[signal]` void QPlaceManagerEngine::finished(QPlaceReply *reply)

This signal is emitted when reply has finished processing.

If reply->error() equals QPlaceReply::NoError then the processing finished successfully.

This signal and QPlaceReply::finished() will be emitted at the same time.

Note: Do not delete the reply object in the slot connected to this signal. Use deleteLater() instead.

### `[virtual]` QPlaceContentReply *QPlaceManagerEngine::getPlaceContent(const QPlaceContentRequest &request)

Retrieves content for a place according to the parameters specified in request.

### `[virtual]` QPlaceDetailsReply *QPlaceManagerEngine::getPlaceDetails(const QString &placeId)

Retrieves details of place corresponding to the given placeId.

### `[virtual]` QPlaceReply *QPlaceManagerEngine::initializeCategories()

Initializes the categories of the manager engine.

### `[virtual]` QList<QLocale> QPlaceManagerEngine::locales() const

Returns a list of preferred locales. The locales are used as a hint to the manager engine for what language place and category details should be returned in.

If the first specified locale cannot be accommodated, the manager engine falls back to the next and so forth.

Support for locales may vary from provider to provider. For those that do support it, by default, the global default locale will be used. If the manager engine has no locales assigned to it, it implicitly uses the global default locale. For engines that do not support locales, the locale list is always empty.

See also setLocales().

### `[protected]` QPlaceManager *QPlaceManagerEngine::manager() const

Returns the manager instance used to create this engine.

### QString QPlaceManagerEngine::managerName() const

Returns the name which this engine implementation uses to distinguish itself from the implementations provided by other plugins.

The manager name is automatically set to be the same as the QGeoServiceProviderFactory::providerName().

### int QPlaceManagerEngine::managerVersion() const

Returns the version of this engine implementation.

The manager version is automatically set to be the same as the QGeoServiceProviderFactory::providerVersion().

### `[virtual]` QPlaceMatchReply *QPlaceManagerEngine::matchingPlaces(const QPlaceMatchRequest &request)

Returns a reply which contains a list of places which correspond/match those specified in request.

### `[virtual]` QString QPlaceManagerEngine::parentCategoryId(const QString &categoryId) const

Returns the parent category identifier of the category corresponding to categoryId.

### `[signal]` void QPlaceManagerEngine::placeAdded(const QString &placeId)

This signal is emitted if a place has been added to the manager engine's datastore. The particular added place is specified by placeId.

This signal is only emitted by manager engines that support the QPlaceManager::NotificationsFeature.

See also dataChanged().

### `[signal]` void QPlaceManagerEngine::placeRemoved(const QString &placeId)

This signal is emitted if a place has been removed from the manager engine's datastore. The particular place that has been removed is specified by placeId.

This signal is only emitted by manager engines that support the QPlaceManager::NotificationsFeature.

See also dataChanged().

### `[signal]` void QPlaceManagerEngine::placeUpdated(const QString &placeId)

This signal is emitted if a place has been modified in the manager engine's datastore. The particular modified place is specified by placeId.

This signal is only emitted by manager engines that support the QPlaceManager::NotificationsFeature.

See also dataChanged().

### `[virtual]` QPlaceIdReply *QPlaceManagerEngine::removeCategory(const QString &categoryId)

Removes the category corresponding to categoryId from the manager engine's datastore.

### `[virtual]` QPlaceIdReply *QPlaceManagerEngine::removePlace(const QString &placeId)

Removes the place corresponding to placeId from the manager engine's datastore.

### `[virtual]` QPlaceIdReply *QPlaceManagerEngine::saveCategory(const QPlaceCategory &category, const QString &parentId)

Saves a category that is a child of the category specified by parentId. An empty parentId means category is saved as a top level category.

### `[virtual]` QPlaceIdReply *QPlaceManagerEngine::savePlace(const QPlace &place)

Saves a specified place to the manager engine's datastore.

### `[virtual]` QPlaceSearchReply *QPlaceManagerEngine::search(const QPlaceSearchRequest &request)

Searches for places according to the parameters specified in request.

### `[virtual]` QPlaceSearchSuggestionReply *QPlaceManagerEngine::searchSuggestions(const QPlaceSearchRequest &request)

Requests a set of search term suggestions according to the parameters specified in request.

### `[virtual]` void QPlaceManagerEngine::setLocales(const QList<QLocale> &locales)

Set the list of preferred locales.

See also locales().