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class QgsFeatureRequest
{
%TypeHeaderCode
#include <qgsfeaturerequest.h>
%End
public:
enum Flag
{
NoFlags,
NoGeometry, //!< Geometry is not required. It may still be returned if e.g. required for a filter condition.
SubsetOfAttributes, //!< Fetch only a subset of attributes (setSubsetOfAttributes sets this flag)
ExactIntersect //!< Use exact geometry intersection (slower) instead of bounding boxes
};
typedef QFlags<QgsFeatureRequest::Flag> Flags;
enum FilterType
{
FilterNone, //!< No filter is applied
FilterRect, //!< Filter using a rectangle, no need to set NoGeometry
FilterFid, //!< Filter using feature ID
FilterExpression, //!< Filter using expression
FilterFids //!< Filter using feature IDs
};
//! construct a default request: for all features get attributes and geometries
QgsFeatureRequest();
//! construct a request with feature ID filter
explicit QgsFeatureRequest( QgsFeatureId fid );
//! construct a request with rectangle filter
explicit QgsFeatureRequest( const QgsRectangle& rect );
//! construct a request with a filter expression
explicit QgsFeatureRequest( const QgsExpression& expr );
FilterType filterType() const;
//! Set rectangle from which features will be taken. Empty rectangle removes the filter.
//!
QgsFeatureRequest& setFilterRect( const QgsRectangle& rect );
const QgsRectangle& filterRect() const;
//! Set feature ID that should be fetched.
QgsFeatureRequest& setFilterFid( qint64 fid );
qint64 filterFid() const;
//! Set feature ID that should be fetched.
QgsFeatureRequest& setFilterFids( QgsFeatureIds fids );
const QgsFeatureIds& filterFids() const;
//! Set filter expression. {@see QgsExpression}
QgsFeatureRequest& setFilterExpression( const QString& expression );
QgsExpression* filterExpression() const;
//! Set flags that affect how features will be fetched
QgsFeatureRequest& setFlags( Flags flags );
const Flags& flags() const;
//! Set a subset of attributes that will be fetched. Empty list means that all attributes are used.
//! To disable fetching attributes, reset the FetchAttributes flag (which is set by default)
QgsFeatureRequest& setSubsetOfAttributes( const QgsAttributeList& attrs );
const QgsAttributeList& subsetOfAttributes() const;
//! Set a subset of attributes by names that will be fetched
QgsFeatureRequest& setSubsetOfAttributes( const QStringList& attrNames, const QgsFields& fields );
//! Set a simplification method for geometries that will be fetched
//! @note added in 2.2
QgsFeatureRequest& setSimplifyMethod( const QgsSimplifyMethod& simplifyMethod );
//! Get simplification method for geometries that will be fetched
//! @note added in 2.2
const QgsSimplifyMethod& simplifyMethod() const;
/**
* Check if a feature is accepted by this requests filter
*
* @param feature The feature which will be tested
*
* @return true, if the filter accepts the feature
*
* @note added in 2.1
*/
bool acceptFeature( const QgsFeature& feature );
};
/** base class that can be used for any class that is capable of returning features
* @note added in 2.4
*/
class QgsAbstractFeatureSource
{
%TypeHeaderCode
#include <qgsfeaturerequest.h>
%End
public:
virtual ~QgsAbstractFeatureSource();
virtual QgsFeatureIterator getFeatures( const QgsFeatureRequest& request ) = 0;
protected:
void iteratorOpened( QgsAbstractFeatureIterator* it );
void iteratorClosed( QgsAbstractFeatureIterator* it );
};
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