/** \ingroup core
* A convenience class for writing vector files to disk.
There are two possibilities how to use this class:
1. static call to QgsVectorFileWriter::writeAsShapefile(...) which saves the whole vector layer
2. create an instance of the class and issue calls to addFeature(...)
Currently supports only writing to shapefiles, but shouldn't be a problem to add capability
to support other OGR-writable formats.
*/
class QgsVectorFileWriter
{
%TypeHeaderCode
#include <qgsvectorfilewriter.h>
#include <qgsfield.h>
%End
public:
enum OptionType
{
Set,
String,
Int,
Hidden
};
class Option
{
public:
Option( const QString& docString, QgsVectorFileWriter::OptionType type );
virtual ~Option();
QString docString;
QgsVectorFileWriter::OptionType type;
};
class SetOption : QgsVectorFileWriter::Option
{
public:
SetOption( const QString& docString, const QStringList& values, const QString& defaultValue, bool allowNone = false );
QSet<QString> values;
QString defaultValue;
bool allowNone;
};
class StringOption: QgsVectorFileWriter::Option
{
public:
StringOption( const QString& docString, const QString& defaultValue = QString() );
QString defaultValue;
};
class IntOption: QgsVectorFileWriter::Option
{
public:
IntOption( const QString& docString, int defaultValue );
int defaultValue;
};
class BoolOption : QgsVectorFileWriter::SetOption
{
public:
BoolOption( const QString& docString, bool defaultValue );
};
class HiddenOption : QgsVectorFileWriter::Option
{
public:
HiddenOption( const QString& value );
QString mValue;
};
struct MetaData
{
MetaData();
MetaData( const QString& longName, const QString& trLongName, const QString& glob, const QString& ext, const QMap<QString, QgsVectorFileWriter::Option*>& driverOptions, const QMap<QString, QgsVectorFileWriter::Option*>& layerOptions );
QString longName;
QString trLongName;
QString glob;
QString ext;
QMap<QString, QgsVectorFileWriter::Option*> driverOptions;
QMap<QString, QgsVectorFileWriter::Option*> layerOptions;
};
enum WriterError
{
NoError,
ErrDriverNotFound,
ErrCreateDataSource,
ErrCreateLayer,
ErrAttributeTypeUnsupported,
ErrAttributeCreationFailed,
ErrProjection,
ErrFeatureWriteFailed,
ErrInvalidLayer,
};
enum SymbologyExport
{
NoSymbology, //export only data
FeatureSymbology, //Keeps the number of features and export symbology per feature
SymbolLayerSymbology //Exports one feature per symbol layer (considering symbol levels)
};
/** Write contents of vector layer to an (OGR supported) vector formt
* @param layer layer to write
* @param fileName file name to write to
* @param fileEncoding encoding to use
* @param destCRS pointer to CRS to reproject exported geometries to
* @param driverName OGR driver to use
* @param onlySelected write only selected features of layer
* @param errorMessage pointer to buffer fo error message
* @param datasourceOptions list of OGR data source creation options
* @param layerOptions list of OGR layer creation options
* @param skipAttributeCreation only write geometries
* @param newFilename QString pointer which will contain the new file name created (in case it is different to fileName).
* @param symbologyExport symbology to export
* @param symbologyScale scale of symbology
* @param filterExtent if not a null pointer, only features intersecting the extent will be saved (added in QGIS 2.4)
* @param overrideGeometryType set to a valid geometry type to override the default geometry type for the layer. This parameter
* allows for conversion of geometryless tables to null geometries, etc (added in QGIS 2.14)
* @param forceMulti set to true to force creation of multi* geometries (added in QGIS 2.14)
* @param includeZ set to true to include z dimension in output. This option is only valid if overrideGeometryType is set. (added in QGIS 2.14)
* @param attributes attributes to export (empty means all unless skipAttributeCreation is set)
*/
static WriterError writeAsVectorFormat( QgsVectorLayer* layer,
const QString& fileName,
const QString& fileEncoding,
const QgsCoordinateReferenceSystem *destCRS,
const QString& driverName = "ESRI Shapefile",
bool onlySelected = false,
QString *errorMessage = 0,
const QStringList &datasourceOptions = QStringList(),
const QStringList &layerOptions = QStringList(),
bool skipAttributeCreation = false,
QString *newFilename = 0,
SymbologyExport symbologyExport = NoSymbology,
double symbologyScale = 1.0,
const QgsRectangle* filterExtent = 0,
QgsWKBTypes::Type overrideGeometryType = QgsWKBTypes::Unknown,
bool forceMulti = false,
bool includeZ = false,
QgsAttributeList attributes = QgsAttributeList()
);
/** Writes a layer out to a vector file.
* @param layer layer to write
* @param fileName file name to write to
* @param fileEncoding encoding to use
* @param ct pointer to coordinate transform to reproject exported geometries with
* @param driverName OGR driver to use
* @param onlySelected write only selected features of layer
* @param errorMessage pointer to buffer fo error message
* @param datasourceOptions list of OGR data source creation options
* @param layerOptions list of OGR layer creation options
* @param skipAttributeCreation only write geometries
* @param newFilename QString pointer which will contain the new file name created (in case it is different to fileName).
* @param symbologyExport symbology to export
* @param symbologyScale scale of symbology
* @param filterExtent if not a null pointer, only features intersecting the extent will be saved (added in QGIS 2.4)
* @param overrideGeometryType set to a valid geometry type to override the default geometry type for the layer. This parameter
* allows for conversion of geometryless tables to null geometries, etc (added in QGIS 2.14)
* @param forceMulti set to true to force creation of multi* geometries (added in QGIS 2.14)
* @param includeZ set to true to include z dimension in output. This option is only valid if overrideGeometryType is set. (added in QGIS 2.14)
* @param attributes attributes to export (empty means all unless skipAttributeCreation is set)
* @note added in 2.2
*/
static WriterError writeAsVectorFormat( QgsVectorLayer* layer,
const QString& fileName,
const QString& fileEncoding,
const QgsCoordinateTransform* ct,
const QString& driverName = "ESRI Shapefile",
bool onlySelected = false,
QString *errorMessage = 0,
const QStringList &datasourceOptions = QStringList(),
const QStringList &layerOptions = QStringList(),
bool skipAttributeCreation = false,
QString *newFilename = 0,
SymbologyExport symbologyExport = NoSymbology,
double symbologyScale = 1.0,
const QgsRectangle* filterExtent = 0,
QgsWKBTypes::Type overrideGeometryType = QgsWKBTypes::Unknown,
bool forceMulti = false,
bool includeZ = false,
QgsAttributeList attributes = QgsAttributeList()
);
/** Create a new vector file writer */
QgsVectorFileWriter( const QString& vectorFileName,
const QString& fileEncoding,
const QgsFields& fields,
QGis::WkbType geometryType,
const QgsCoordinateReferenceSystem* srs,
const QString& driverName = "ESRI Shapefile",
const QStringList &datasourceOptions = QStringList(),
const QStringList &layerOptions = QStringList(),
QString *newFilename = nullptr,
SymbologyExport symbologyExport = NoSymbology
);
/** Create a new vector file writer */
QgsVectorFileWriter( const QString& vectorFileName,
const QString& fileEncoding,
const QgsFields& fields,
QgsWKBTypes::Type geometryType,
const QgsCoordinateReferenceSystem* srs,
const QString& driverName = "ESRI Shapefile",
const QStringList &datasourceOptions = QStringList(),
const QStringList &layerOptions = QStringList(),
QString *newFilename = nullptr,
SymbologyExport symbologyExport = NoSymbology
);
/** Returns map with format filter string as key and OGR format key as value*/
static QMap< QString, QString> supportedFiltersAndFormats();
/** Returns driver list that can be used for dialogs. It contains all OGR drivers
* + some additional internal QGIS driver names to distinguish between more
* supported formats of the same OGR driver
*/
static QMap< QString, QString> ogrDriverList();
/** Returns filter string that can be used for dialogs*/
static QString fileFilterString();
/** Creates a filter for an OGR driver key*/
static QString filterForDriver( const QString& driverName );
/** Converts codec name to string passed to ENCODING layer creation option of OGR Shapefile*/
static QString convertCodecNameForEncodingOption( const QString &codecName );
/** Checks whether there were any errors in constructor */
WriterError hasError();
/** Retrieves error message */
QString errorMessage();
/** Add feature to the currently opened data source */
bool addFeature( QgsFeature& feature, QgsFeatureRendererV2* renderer = 0, QGis::UnitType outputUnit = QGis::Meters );
//! @note not available in python bindings
// QMap<int, int> attrIdxToOgrIdx();
/** Close opened shapefile for writing */
~QgsVectorFileWriter();
/** Delete a shapefile (and its accompanying shx / dbf / prf)
* @param theFileName /path/to/file.shp
* @return bool true if the file was deleted successfully
*/
static bool deleteShapeFile( const QString& theFileName );
SymbologyExport symbologyExport() const;
void setSymbologyExport( SymbologyExport symExport );
double symbologyScaleDenominator() const;
void setSymbologyScaleDenominator( double d );
static bool driverMetadata( const QString& driverName, MetaData& driverMetadata );
protected:
//! @note not available in python bindings
// OGRGeometryH createEmptyGeometry( QGis::WkbType wkbType );
private:
QgsVectorFileWriter( const QgsVectorFileWriter& rh );
};