QGIS API Documentation  2.5.0-Master
 All Classes Namespaces Files Functions Variables Typedefs Enumerations Enumerator Friends Macros Modules Pages
Public Member Functions | List of all members
QgsCacheIndexFeatureId Class Reference

#include <qgscacheindexfeatureid.h>

Inheritance diagram for QgsCacheIndexFeatureId:
Inheritance graph
[legend]

Public Member Functions

 QgsCacheIndexFeatureId (QgsVectorLayerCache *)
 
virtual void flushFeature (const QgsFeatureId fid)
 Is called, whenever a feature is removed from the cache. More...
 
virtual void flush ()
 Sometimes, the whole cache changes its state and its easier to just withdraw everything. More...
 
virtual void requestCompleted (QgsFeatureRequest featureRequest, QgsFeatureIds fids)
 Implement this method to update the the indices, in case you need information contained by the request to properly index. More...
 
virtual bool getCacheIterator (QgsFeatureIterator &featureIterator, const QgsFeatureRequest &featureRequest)
 Is called, when a feature request is issued on a cached layer. More...
 
- Public Member Functions inherited from QgsAbstractCacheIndex
 QgsAbstractCacheIndex ()
 
virtual ~QgsAbstractCacheIndex ()
 

Constructor & Destructor Documentation

QgsCacheIndexFeatureId::QgsCacheIndexFeatureId ( QgsVectorLayerCache cachedVectorLayer)

Member Function Documentation

void QgsCacheIndexFeatureId::flush ( )
virtual

Sometimes, the whole cache changes its state and its easier to just withdraw everything.

In this case, this method is issued. Be sure to clear all cache information in here.

Implements QgsAbstractCacheIndex.

void QgsCacheIndexFeatureId::flushFeature ( const QgsFeatureId  fid)
virtual

Is called, whenever a feature is removed from the cache.

You should update your indexes, so they become invalid in case this feature was required to successfuly answer a request.

Implements QgsAbstractCacheIndex.

bool QgsCacheIndexFeatureId::getCacheIterator ( QgsFeatureIterator featureIterator,
const QgsFeatureRequest featureRequest 
)
virtual

Is called, when a feature request is issued on a cached layer.

If this cache index is able to completely answer the feature request, it will return true and write the list of feature ids of cached features to cachedFeatures. If it is not able it will return false and the cachedFeatures state is undefined.

Parameters
featureIteratorA reference to a QgsFeatureIterator. A valid featureIterator will be assigned in case this index is able to answer the request and the return value is true.
featureRequestThe feature request, for which this index is queried.
Returns
True, if this index holds the information to answer the request.

Implements QgsAbstractCacheIndex.

void QgsCacheIndexFeatureId::requestCompleted ( QgsFeatureRequest  featureRequest,
QgsFeatureIds  fids 
)
virtual

Implement this method to update the the indices, in case you need information contained by the request to properly index.

(E.g. spatial index) Does nothing by default

Parameters
featureRequestThe feature request that was answered
fidsThe feature ids that have been returned

Reimplemented from QgsAbstractCacheIndex.


The documentation for this class was generated from the following files: