class QgsVectorDataProvider : QgsDataProvider { %TypeHeaderCode #include %End public: // If you add to this, please also add to capabilitiesString() /** * enumeration with capabilities that providers might implement */ enum Capability { NoCapabilities = 0, AddFeatures = 1, DeleteFeatures = 2, ChangeAttributeValues = 4, AddAttributes = 8, DeleteAttributes = 16, SaveAsShapefile = 32, CreateSpatialIndex = 64, SelectAtId = 128, ChangeGeometries = 256, SelectGeometryAtId = 512, RandomSelectGeometryAtId = 1024, SequentialSelectGeometryAtId = 2048 }; /** * Constructor of the vector provider * @param uri uniform resource locator (URI) for a dataset */ QgsVectorDataProvider(QString uri = QString()); /** * Destructor */ virtual ~QgsVectorDataProvider(); /** * Returns the permanent storage type for this layer as a friendly name. */ virtual QString storageType() const; /** Select features based on a bounding rectangle. Features can be retrieved with calls to getNextFeature. * @param fetchAttributes list of attributes which should be fetched * @param rect spatial filter * @param fetchGeometry true if the feature geometry should be fetched * @param useIntersect true if an accurate intersection test should be used, * false if a test based on bounding box is sufficient */ virtual void select(QList fetchAttributes = QList(), QgsRect rect = QgsRect(), bool fetchGeometry = true, bool useIntersect = false) = 0; /** * Update the feature count based on current spatial filter. If not * overridden in the data provider this function returns -1 */ virtual long updateFeatureCount(); /** * Gets the feature at the given feature ID. * @param featureId id of the feature * @param feature feature which will receive the data * @param fetchGeoemtry if true, geometry will be fetched from the provider * @param fetchAttributes a list containing the indexes of the attribute fields to copy * @return True when feature was found, otherwise false */ virtual bool getFeatureAtId(int featureId, QgsFeature& feature, bool fetchGeometry = true, QList fetchAttributes = QList()); /** * Get the next feature resulting from a select operation. * @param feature feature which will receive data from the provider * @return true when there was a feature to fetch, false when end was hit */ virtual bool getNextFeature(QgsFeature& feature) = 0; /** * Get feature type. * @return int representing the feature type */ virtual QGis::WKBTYPE geometryType() const = 0; /** * Number of features in the layer * @return long containing number of features */ virtual long featureCount() const = 0; /** * Number of attribute fields for a feature in the layer */ virtual uint fieldCount() const = 0; /** * Return a map of indexes with field names for this layer * @return map of fields */ virtual const QMap & fields() const = 0; /** * Return a short comment for the data that this provider is * providing access to (e.g. the comment for postgres table). */ virtual QString dataComment() const; /** Restart reading features from previous select operation */ virtual void reset() = 0; /** * Returns the minimum value of an attributs * @param index the index of the attribute * * Default implementation walks all numeric attributes and caches minimal * and maximal values. If provider has facilities to retreive minimal * value directly, override this function. */ virtual QVariant minValue(int index); /** * Returns the maximum value of an attributs * @param index the index of the attribute * * Default implementation walks all numeric attributes and caches minimal * and maximal values. If provider has facilities to retreive maximal * value directly, override this function. */ virtual QVariant maxValue(int index); /** * Return unique values of an attribute * @param index the index of the attribute * @param values reference to the list to fill * * Default implementation simply iterates the features */ virtual void getUniqueValues(int index, QStringList &uniqueValues); /** * Adds a list of features * @return true in case of success and false in case of failure */ virtual bool addFeatures(QList & flist /In,Out/); /** * Deletes a feature * @param id list containing feature ids to delete * @return true in case of success and false in case of failure */ virtual bool deleteFeatures(const QSet & id); /** * Adds new attributes * @param attributes map with attribute name as key and type as value * @return true in case of success and false in case of failure */ virtual bool addAttributes(const QMap & attributes); /** * Deletes existing attributes * @param attributes a set containing indexes of attributes * @return true in case of success and false in case of failure */ virtual bool deleteAttributes(const QSet & attributes); /** * Changes attribute values of existing features. * @param attr_map a map containing changed attributes * @return true in case of success and false in case of failure */ virtual bool changeAttributeValues(const QMap > & attr_map); /** * Returns the default value for field specified by @c fieldId */ virtual QVariant getDefaultValue(int fieldId); /** * Changes geometries of existing features * @param geometry_map A std::map containing the feature IDs to change the geometries of. * the second map parameter being the new geometries themselves * @return true in case of success and false in case of failure */ virtual bool changeGeometryValues(QMap & geometry_map); /** * Creates a spatial index on the datasource (if supported by the provider type). * @return true in case of success */ virtual bool createSpatialIndex(); /** Returns a bitmask containing the supported capabilities Note, some capabilities may change depending on whether a spatial filter is active on this provider, so it may be prudent to check this value per intended operation. */ virtual int capabilities() const; /** * Returns the above in friendly format. */ QString capabilitiesString() const; /** * Set encoding used for accessing data from layer */ virtual void setEncoding(const QString& e); /** * Get encoding which is used for accessing data */ QString encoding() const; /** * Returns the index of a field name or -1 if the field does not exist */ int indexFromFieldName(const QString& fieldName) const; /** * Return list of indexes to fetch all attributes in getNextFeature() */ QList allAttributesList(); /**Returns the names of the numerical types*/ const QSet& supportedNativeTypes() const; /** * Set whether provider should return also features that don't have * associated geometry. FALSE by default */ void setFetchFeaturesWithoutGeom(bool fetch); };