QPlaceSearchRequest Class

The QPlaceSearchRequest class represents the set of parameters for a search request. 更多...

头: #include <QPlaceSearchRequest>
qmake: QT += location
Since: Qt 5.6

该类在 Qt 5.6 引入。

公共类型

enum RelevanceHint { UnspecifiedHint, DistanceHint, LexicalPlaceNameHint }

公共函数

QPlaceSearchRequest (const QPlaceSearchRequest & other )
QPlaceSearchRequest ()
QPlaceSearchRequest & operator= (const QPlaceSearchRequest & other )
~QPlaceSearchRequest ()
QList<QPlaceCategory> categories () const
void clear ()
int limit () const
QString recommendationId () const
QPlaceSearchRequest::RelevanceHint relevanceHint () const
QGeoShape searchArea () const
QVariant searchContext () const
QString searchTerm () const
void setCategories (const QList<QPlaceCategory> & categories )
void setCategory (const QPlaceCategory & category )
void setLimit (int limit )
void setRecommendationId (const QString & placeId )
void setRelevanceHint (QPlaceSearchRequest::RelevanceHint hint )
void setSearchArea (const QGeoShape & area )
void setSearchContext (const QVariant & context )
void setSearchTerm (const QString & term )
void setVisibilityScope (QLocation::VisibilityScope scope )
QLocation::VisibilityScope visibilityScope () const
bool operator!= (const QPlaceSearchRequest & other ) const
bool operator== (const QPlaceSearchRequest & other ) const

详细描述

A typical search request may look like the following:

QPlaceSearchRequest searchRequest;
searchRequest.setSearchTerm("Fast food"); //search term for what we are interested in
//set a search center
searchRequest.setSearchArea(QGeoCircle(QGeoCoordinate(2.3, 48.87)));
//set a distance hint as a relevancy hint.
//closer places have greater weighting in the ranking of results.
searchRequest.setRelevanceHint(QPlaceSearchRequest::DistanceHint);
//use limit to adjust pagination.
//this limits the number of place results to 5 per page.
searchRequest.setLimit(5);
//provide some categories to narrow down search
QList<QPlaceCategory> categories;
categories << diner << restaurant;
searchRequest.setCategories(categories);
					

Note that specifying a search center can be done by setting a circular search area that has a center but no radius. The default radius is set to -1, which indicates an undefined radius. The provider will interpret this as being free to choose its own default radius.

The QPlaceSearchRequest is primarily used with the QPlaceManager to search for places , however it is also used to provide parameters for generating search term suggestions . Note that in this context only some of the parameters may be relevant. For example, the search area is useful in narrowing down relevant search suggestions, while other parameters such as relevance hint are not so applicable.

Also be aware that providers may vary by which parameters they support for example some providers may not support paging while others do, some providers may honor relevance hints while others may completely ignore them, see the plugin documentation 了解更多细节。

成员类型文档编制

enum QPlaceSearchRequest:: RelevanceHint

Defines hints to help rank place results.

常量 描述
QPlaceSearchRequest::UnspecifiedHint 0 No explicit hint has been specified.
QPlaceSearchRequest::DistanceHint 1 Distance to a search center is relevant for the user. Closer places are more highly weighted. This hint is only useful if a circular search area is used in the query.
QPlaceSearchRequest::LexicalPlaceNameHint 2 Alphabetic ordering of places according to name is relevant to the user.

成员函数文档编制

QPlaceSearchRequest:: QPlaceSearchRequest (const QPlaceSearchRequest & other )

构造副本为 other .

QPlaceSearchRequest:: QPlaceSearchRequest ()

Default constructor. Constructs an new request object.

QPlaceSearchRequest &QPlaceSearchRequest:: operator= (const QPlaceSearchRequest & other )

赋值 other to this search request and returns a reference to this search request.

QPlaceSearchRequest:: ~QPlaceSearchRequest ()

Destroys the request object.

QList < QPlaceCategory > QPlaceSearchRequest:: categories () const

Return the categories to be used in the search request. Places need only to belong to one of the categories to be considered a match by the request.

另请参阅 setCategories ().

void QPlaceSearchRequest:: clear ()

Clears the search request.

int QPlaceSearchRequest:: limit () const

Returns the maximum number of search results to retrieve.

A negative value for limit means that it is undefined. It is left up to the backend provider to choose an appropriate number of results to return. The default limit is -1.

另请参阅 setLimit ().

QString QPlaceSearchRequest:: recommendationId () const

Returns the place id which will be used to search for recommendations for similar places.

另请参阅 setRecommendationId ().

QPlaceSearchRequest::RelevanceHint QPlaceSearchRequest:: relevanceHint () const

Returns the relevance hint of the request. The hint is given to the provider to help but not dictate the ranking of results. For example providing a distance hint may give closer places a higher ranking but it doesn't necessarily mean that he results will be ordered strictly according to distance.

另请参阅 setRelevanceHint ().

QGeoShape QPlaceSearchRequest:: searchArea () const

Returns the search area which will be used to limit search results. The default search area is an invalid QGeoShape , indicating that no specific search area is defined.

另请参阅 setSearchArea ().

QVariant QPlaceSearchRequest:: searchContext () const

Returns backend specific additional search context associated with this place search request. The search context is typically set as part of a proposed search results .

另请参阅 setSearchContext ().

QString QPlaceSearchRequest:: searchTerm () const

Returns the search term.

另请参阅 setSearchTerm ().

void QPlaceSearchRequest:: setCategories (const QList < QPlaceCategory > & categories )

Sets the search request to search from the list of given categories . Any places returned during the search will match at least one of the categories .

另请参阅 categories () 和 setCategory ().

void QPlaceSearchRequest:: setCategory (const QPlaceCategory & category )

Sets the search request to search by a single category

另请参阅 setCategories ().

void QPlaceSearchRequest:: setLimit ( int limit )

Set the maximum number of search results to retrieve to limit .

另请参阅 limit ().

void QPlaceSearchRequest:: setRecommendationId (const QString & placeId )

设置 placeId which will be used to search for recommendations.

另请参阅 recommendationId ().

void QPlaceSearchRequest:: setRelevanceHint ( QPlaceSearchRequest::RelevanceHint hint )

Sets the relevance hint to be used when searching for a place.

另请参阅 relevanceHint ().

void QPlaceSearchRequest:: setSearchArea (const QGeoShape & area )

Sets the search request to search within the given area .

另请参阅 searchArea ().

void QPlaceSearchRequest:: setSearchContext (const QVariant & context )

Sets the search context to context .

注意: This method is intended to be used by geo service plugins when returning search results of type QPlaceSearchResult::ProposedSearchResult .

The search context is used by backends to store additional search context related to the search request. Other relevant fields should also be filled in. For example, if the search context encodes a text search the search term should also be set with setSearchTerm (). The search context allows additional search context to be kept which is not directly accessible via the Qt Location API.

The search context can be of any type storable in a QVariant . The value of the search context is not intended to be use directly by applications.

另请参阅 searchContext ().

void QPlaceSearchRequest:: setSearchTerm (const QString & term )

Sets the search term .

另请参阅 searchTerm ().

void QPlaceSearchRequest:: setVisibilityScope ( QLocation::VisibilityScope scope )

Sets the visibility scope used when searching for places.

另请参阅 visibilityScope ().

QLocation::VisibilityScope QPlaceSearchRequest:: visibilityScope () const

Returns the visibility scope used when searching for places. The default value is QLocation::UnspecifiedVisibility meaning that no explicit scope has been assigned. Places of any scope may be returned during the search.

另请参阅 setVisibilityScope ().

bool QPlaceSearchRequest:: operator!= (const QPlaceSearchRequest & other ) const

返回 true 若 other is not equal to this search request, otherwise returns false.

bool QPlaceSearchRequest:: operator== (const QPlaceSearchRequest & other ) const

返回 true 若 other is equal to this search request, otherwise returns false.