QGeoSearchManagerEngine Class Reference
The QGeoSearchManagerEngine class provides an interface and convenience methods to implementers of QGeoServiceProvider plugins who want to provide support for searching operations related to geographic data. More...
#include <QGeoSearchManagerEngine>
Public Functions
Signals
void | error ( QGeoSearchReply * reply, QGeoSearchReply::Error error, QString errorString = QString() ) |
void | finished ( QGeoSearchReply * reply ) |
Protected Functions
Detailed Description
The QGeoSearchManagerEngine class provides an interface and convenience methods to implementers of QGeoServiceProvider plugins who want to provide support for searching operations related to geographic data.
In the default implementation, supportsGeocoding() returns false while geocode(const QGeoAddress &address,const QGeoBoundingBox &bounds) and geocode(const QGeoCoordinate &coordinate,const QGeoBoundingBox &bounds) cause QGeoSearchReply::UnsupportedOptionError to occur.
If the service provider supports geocoding the subclass should provide implementations of geocode(const QGeoAddress &address, const QGeoBoundingBox &bounds) and geocode(const QGeoCoordinate &coordinate, const QGeoBoundingBox &bounds) and and call setSupportsGeocoding(true) at some point in time before either of the geoocode() methods are called.
The placeSearch() function will make use of the QLandmarkManager instances returned by additionalLandmarkManagers(). If a QLandmarkManager is used internally to query the service providers landmark data the QLandmarkManager can be made available to the users with setDefaultLandmarkManager().
The subclass should call setSupportedSearchTypes() at some point in time before placeSearch() is called.
If the service supports searching for places the subclass should provide an implementetation of placeSearch() and call setSupportedSearchTypes() at some point in time before placeSearch() is called.
The functions setSupportsGeocoding() and setSupportedSearchTypes() are used to configure the reported capabilities of the engine. If the capabilities of an engine differ from the default values these functions should be used so that the reported capabilies are accurate.
It is important that this is done before geocode(const QGeoAddress &address,const QGeoBoundingBox &bounds), geocode(const QGeoCoordinate &coordinate,const QGeoBoundingBox &bounds), placeSearch(const QString &searchString, QGeoSearchManager::SearchTypes searchTypes, constQGeoBoundingBox &bounds or any of the capability reporting functions are used to prevent incorrect or inconsistent behaviour.
A subclass of QGeoSearchManagerEngine will often make use of a subclass fo QGeoSearchReply internally, in order to add any engine-specific data (such as a QNetworkReply object for network-based services) to the QGeoSearchReply instances used by the engine.
See also QGeoSearchManager.
Member Function Documentation
QGeoSearchManagerEngine::QGeoSearchManagerEngine ( const QMap<QString, QString> & parameters, QObject * parent = 0 )
Constructs a new engine with the specified parent, using parameters to pass any implementation specific data to the engine.
QGeoSearchManagerEngine::~QGeoSearchManagerEngine () [virtual]
Destroys this engine.
void QGeoSearchManagerEngine::addAdditionalLandmarkManager ( QLandmarkManager * landmarkManager )
Adds landmarkManager to the list of landmark managers that will be used with placeSearch().
These landmark managers will be used along with the landmark manager returned by defaultLandmarkManager().
QList<QLandmarkManager *> QGeoSearchManagerEngine::additionalLandmarkManagers () const
Returns the landmark managers that will be used with placeSearch().
These landmark managers will be used along with the landmark manager returned by defaultLandmarkManager().
See also setAdditionalLandmarkManagers().
QLandmarkManager * QGeoSearchManagerEngine::defaultLandmarkManager () const
Returns the landmark manager provided by the service provider for use with placeSearch().
Will return 0 if the no landmark manager is associated with the service provider. This does not indicate that placeSearch() does not support landmark searching, only that any landmark searching which occurs within in placeSearch() is done without the use of a QLandmarkManager.
See also setDefaultLandmarkManager().
void QGeoSearchManagerEngine::error ( QGeoSearchReply * reply, QGeoSearchReply::Error error, QString errorString = QString() ) [signal]
This signal is emitted when an error has been detected in the processing of reply. The QGeoSearchManagerEngine::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.
This signal and QGeoSearchReply::error() will be emitted at the same time.
Note: Do no delete the reply object in the slot connected to this signal. Use deleteLater() instead.
void QGeoSearchManagerEngine::finished ( QGeoSearchReply * reply ) [signal]
This signal is emitted when reply has finished processing.
If reply::error() equals QGeoSearchReply::NoError then the processing finished successfully.
This signal and QGeoSearchReply::finished() will be emitted at the same time.
Note: Do no delete the reply object in the slot connected to this signal. Use deleteLater() instead.
Begins the geocoding of address. Geocoding is the process of finding a coordinate that corresponds to a given address.
A QGeoSearchReply object will be returned, which can be used to manage the geocoding operation and to return the results of the operation.
This engine and the returned QGeoSearchReply object will emit signals indicating if the operation completes or if errors occur.
If supportsGeocoding() returns false an QGeoSearchReply::UnsupportedOptionError will occur.
Once the operation has completed, QGeoSearchReply::places() can be used to retrieve the results, which will consist of a list of QGeoPlace objects. These object represent a combination of coordinate and address data.
The address data returned in the results may be different from address. This will usually occur if the geocoding service backend uses a different canonical form of addresses or if address was only partially filled out.
If bounds is a valid QGeoBoundingBox it will be used to limit the results to those that are contained by bounds. This is particularly useful if address is only partially filled out, as the service will attempt to geocode all matches for the specified data.
The user is responsible for deleting the returned reply object, although this can be done in the slot connected to QGeoSearchManagerEngine::finished(), QGeoSearchManagerEngine::error(), QGeoSearchReply::finished() or QGeoSearchReply::error() with deleteLater().
Begins the reverse geocoding of coordinate. Reverse geocoding is the process of finding an address that corresponds to a given coordinate.
A QGeoSearchReply object will be returned, which can be used to manage the reverse geocoding operation and to return the results of the operation.
This engine and the returned QGeoSearchReply object will emit signals indicating if the operation completes or if errors occur.
If supportsGeocoding() returns false an QGeoSearchReply::UnsupportedOptionError will occur.
At that point QGeoSearchReply::places() can be used to retrieve the results, which will consist of a list of QGeoPlace objects. These object represent a combination of coordinate and address data.
The coordinate data returned in the results may be different from coordinate. This will usually occur if the reverse geocoding service backend shifts the coordinates to be closer to the matching addresses, or if the backend returns results at multiple levels of detail.
If multiple results are returned by the reverse geocoding service backend they will be provided in order of specificity. This normally occurs if the backend is configured to reverse geocode across multiple levels of detail. As an example, some services will return address and coordinate pairs for the street address, the city, the state and the country.
If bounds is a valid QGeoBoundingBox it will be used to limit the results to those that are contained by bounds.
The user is responsible for deleting the returned reply object, although this can be done in the slot connected to QGeoSearchManagerEngine::finished(), QGeoSearchManagerEngine::error(), QGeoSearchReply::finished() or QGeoSearchReply::error() with deleteLater().
QString QGeoSearchManagerEngine::managerName () const
Returns the name which this engine implementation uses to distinguish itself from the implementations provided by other plugins.
The combination of managerName() and managerVersion() should be unique amongst plugin implementations.
QMap<QString, QString> QGeoSearchManagerEngine::managerParameters () const
Returns the parameters used in the creation of this engine object.
int QGeoSearchManagerEngine::managerVersion () const
Returns the version of this engine implementation.
The combination of managerName() and managerVersion() should be unique amongst plugin implementations.
Begins searching for a place matching searchString. The value of searchTypes will determine whether the search is for addresses only, for landmarks only or for both.
A QGeoSearchReply object will be returned, which can be used to manage the geocoding operation and to return the results of the operation.
This engine and the returned QGeoSearchReply object will emit signals indicating if the operation completes or if errors occur.
If supportsGeocoding() returns false and searchTypes is QGeoSearchManagerEngine::SearchGeocode an QGeoSearchReply::UnsupportedOptionError will occur.
Once the operation has completed, QGeoSearchReply::places() can be used to retrieve the results, which will consist of a list of QGeoPlace objects. These object represent a combination of coordinate and address data.
If any of the QGeoPlace instances in the results have landmark associated data, QGeoPlace::type() will return QGeoPlace::LandmarkType and QLandmark::QLandmark(const QGeoPlace &place) can be used to convert the QGeoPlace instance into a QLandmark instance.
If searchTypes is QGeoSearchManagerEngine::SearchLandmarks or QGeoSearchManagerEngine::SearchAll, a free text landmark search will be performed. The results will be a combination of the backend specific landmark search and the same free text search applied to each of the QLandmarkManager instances in additionalLandmarkManagers().
If bounds is a valid QGeoBoundingBox it will be used to limit the results to those that are contained by bounds.
The user is responsible for deleting the returned reply object, although this can be done in the slot connected to QGeoSearchManagerEngine::finished(), QGeoSearchManagerEngine::error(), QGeoSearchReply::finished() or QGeoSearchReply::error() with deleteLater().
void QGeoSearchManagerEngine::setAdditionalLandmarkManagers ( const QList<QLandmarkManager *> & landmarkManagers )
Sets the landmark managers to be used with placeSearch() to landmarkManagers.
These landmark managers will be used along with the landmark manager returned by defaultLandmarkManager().
See also additionalLandmarkManagers().
void QGeoSearchManagerEngine::setDefaultLandmarkManager ( QLandmarkManager * landmarkManager ) [protected]
Sets the landmark manager provided by the service provider for use with placeSearch() to landmarkManager.
This should only be set if placeSearch() makes use of a QLandmarkManager instance to provide landmark searching functionality.
It is important that subclasses use this method to ensure that the engine is able to carry out landmark searches. If this function is not used the engine will not be able to use or return the default landmark manager.
See also defaultLandmarkManager().
void QGeoSearchManagerEngine::setSupportedSearchTypes ( QGeoSearchManager::SearchTypes searchTypes ) [protected]
Sets the search types supported by the placeSearch() with this engine to searchTypes.
It is important that subclasses use this method to ensure that the engine reports its capabilities correctly. If this function is not used the engine will report that it does not support any search types.
See also supportedSearchTypes().
void QGeoSearchManagerEngine::setSupportsGeocoding ( bool supported ) [protected]
Sets whether this engine supports geocoding operations to supported.
It is important that subclasses use this method to ensure that the engine reports its capabilities correctly. If this function is not used the engine will report that it does not support geocoding operations.
See also supportsGeocoding().
Returns the search types supported by the placeSearch() with this engine.
See also setSupportedSearchTypes().
bool QGeoSearchManagerEngine::supportsGeocoding () const
Returns whether this engine supports geocoding operations.
See also setSupportsGeocoding().