QGeoSearchManagerEngine

Since: 1.1

#include <QtLocationSubset/QGeoSearchManagerEngine>

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() and supportsReverseGeocoding() returns false while geocode() and reverseGeocode() cause QGeoSearchReply::UnsupportedOptionError to occur.

If the service provider supports geocoding the subclass should provide an implementation of geocode() and call setSupportsGeocoding(true) at some point in time before geoocode() is called.

Similarly, if the service provider supports reverse geocoding the subclass should provide an implementation reverseGeocode() and call setSupportsReverseGeocoding(true) at some point in time before reverseGeoocode() is called.

The subclass should call setSupportedSearchTypes() at some point in time before search() is called.

If the service supports searching for places the subclass should provide an implementetation of search() and call setSupportedSearchTypes() at some point in time before search() is called.

A subclass of QGeoSearchManagerEngine will often make use of a subclass of 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.


Overview

Public Functions Index

QGeoSearchManagerEngine (const QMap< QString, QVariant > &parameters, QObject *parent=0)
virtual ~QGeoSearchManagerEngine ()
virtual QGeoSearchReply *geocode (const QGeoAddress &address, QGeoBoundingArea *bounds)
QLocalelocale () const
QStringmanagerName () const
intmanagerVersion () const
virtual QGeoSearchReply *reverseGeocode (const QGeoCoordinate &coordinate, QGeoBoundingArea *bounds)
virtual QGeoSearchReply *search (const QString &searchString, QGeoSearchManager::SearchTypes searchTypes, int limit, int offset, QGeoBoundingArea *bounds)
voidsetLocale (const QLocale &locale)
QGeoSearchManager::SearchTypessupportedSearchTypes () const
boolsupportsGeocoding () const
boolsupportsReverseGeocoding () const

Protected Functions Index

voidsetSupportedSearchTypes (QGeoSearchManager::SearchTypes searchTypes)
voidsetSupportsGeocoding (bool supported)
voidsetSupportsReverseGeocoding (bool supported)

Signals Index

voiderror (QGeoSearchReply *reply, QGeoSearchReply::Error error, QString errorString=QString())
voidfinished (QGeoSearchReply *reply)

Public Functions

QGeoSearchManagerEngine (

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

virtual~QGeoSearchManagerEngine ()

Destructor.

virtualQGeoSearchReply * geocode (

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 objects 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 non-null and a valid QGeoBoundingArea 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().

QLocale locale ()

Returns the locale used to hint to this search manager about what language to use for the results.

QString managerName ()

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.

int managerVersion ()

Returns the version of this engine implementation.

The combination of managerName() and managerVersion() should be unique amongst plugin implementations.

virtualQGeoSearchReply * reverseGeocode (

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 supportsReverseGeocoding() 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 objects 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 non-null and a valid QGeoBoundingArea 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().

virtualQGeoSearchReply * search (
  • const QString &searchString,
  • QGeoSearchManager::SearchTypessearchTypes,
  • intlimit,
  • intoffset,
  • QGeoBoundingArea *bounds )

Begins searching for a place matching searchString.

The value of searchTypes normally determines whether the search is for addresses only, for landmarks only or for both. Note that searching for landmarks is not currently supported in this QtLocation module subset.

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 objects represent a combination of coordinate and address data.

If limit is -1 the entire result set will be returned, otherwise at most limit results will be returned.

The offset parameter is used to ask the search service to not return the first offset results.

The limit and offset results are used together to implement paging.

If bounds is non-null and a valid QGeoBoundingArea 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 setLocale (

Sets the locale to be used by this manager to locale.

If this search manager supports returning the results in different languages, they will be returned in the language of locale.

The locale used defaults to the system locale if this is not set.

QGeoSearchManager::SearchTypes supportedSearchTypes ()

Returns the search types supported by the search() with this engine.

bool supportsGeocoding ()

Returns whether this engine supports geocoding.

bool supportsReverseGeocoding ()

Returns whether this engine supports reverse geocoding.

Protected Functions

void setSupportedSearchTypes (
  • QGeoSearchManager::SearchTypessearchTypes)

Sets the search types supported by the search() 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.

void setSupportsGeocoding (
  • boolsupported)

Sets whether geocoding is supported by this engine 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.

void setSupportsReverseGeocoding (
  • boolsupported)

Sets whether reverse geocoding is supported by this engine 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 reverse geocoding.

Signals

void error (

This signal is emitted when an error has been detected in the processing of \a reply.

Note:

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

void finished (

This signal is emitted when \a 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 that QGeoSearchManagerEngine is in the namespace QtMobilitySubset and this signal is not declared by fully qualifying the QGeoSearchReply parameter. Thus care must be taken when declaring a slot for connection to this signal. For a related example see the description for QGeoPositionInfoSource::positionUpdated().

Note:

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

Last modified: 2014-06-24



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