src/core/qgsvectordataprovider.h

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/***************************************************************************
    qgsvectordataprovider.h - DataProvider Interface for vector layers
     --------------------------------------
    Date                 : 23-Sep-2004
    Copyright            : (C) 2004 by Marco Hugentobler
    email                : marco.hugentobler@autoform.ch
 ***************************************************************************
 *                                                                         *
 *   This program is free software; you can redistribute it and/or modify  *
 *   it under the terms of the GNU General Public License as published by  *
 *   the Free Software Foundation; either version 2 of the License, or     *
 *   (at your option) any later version.                                   *
 *                                                                         *
 ***************************************************************************/
/* $Id: qgsvectordataprovider.h 9781 2008-12-13 11:07:45Z jef $ */
#ifndef QGSVECTORDATAPROVIDER_H
#define QGSVECTORDATAPROVIDER_H


class QTextCodec;

#include <QList>
#include <QSet>
#include <QMap>

//QGIS Includes
#include "qgis.h"
#include "qgsdataprovider.h"
#include "qgsvectorlayer.h"
#include "qgsfield.h"

typedef QMap<QString, QString> QgsNewAttributesMap;
typedef QMap<QString, QVariant::Type> QgsNativeTypeMap;

class CORE_EXPORT QgsVectorDataProvider : public QgsDataProvider
{
  public:

    // If you add to this, please also add to capabilitiesString()
    enum Capability
    {
      NoCapabilities =                     0,
      AddFeatures =                        1,
      DeleteFeatures =               1 <<  1,
      ChangeAttributeValues =        1 <<  2,
      AddAttributes =                1 <<  3,
      DeleteAttributes =             1 <<  4,
      SaveAsShapefile =              1 <<  5,
      CreateSpatialIndex =           1 <<  6,
      SelectAtId =                   1 <<  7,
      ChangeGeometries =             1 <<  8,
      SelectGeometryAtId =           1 <<  9,
      RandomSelectGeometryAtId =     1 << 10,
      SequentialSelectGeometryAtId = 1 << 11
    };

    const static int EditingCapabilities = AddFeatures | DeleteFeatures |
                                           ChangeAttributeValues | ChangeGeometries | AddAttributes | DeleteAttributes;

    QgsVectorDataProvider( QString uri = QString() );

    virtual ~QgsVectorDataProvider();

    virtual QString storageType() const;

    virtual void select( QgsAttributeList fetchAttributes = QgsAttributeList(),
                         QgsRectangle rect = QgsRectangle(),
                         bool fetchGeometry = true,
                         bool useIntersect = false ) = 0;

    virtual long updateFeatureCount();

    virtual bool featureAtId( int featureId,
                              QgsFeature& feature,
                              bool fetchGeometry = true,
                              QgsAttributeList fetchAttributes = QgsAttributeList() );

    virtual bool nextFeature( QgsFeature& feature ) = 0;

    virtual QGis::WkbType geometryType() const = 0;


    virtual long featureCount() const = 0;


    virtual uint fieldCount() const = 0;

    virtual const QgsFieldMap &fields() const = 0;

    virtual QString dataComment() const;

    virtual void rewind() = 0;

    virtual QVariant minimumValue( int index );

    virtual QVariant maximumValue( int index );

    virtual void uniqueValues( int index, QList<QVariant> &uniqueValues );

    virtual bool addFeatures( QgsFeatureList &flist );

    virtual bool deleteFeatures( const QgsFeatureIds &id );

    virtual bool addAttributes( const QgsNewAttributesMap & attributes );

    virtual bool deleteAttributes( const QgsAttributeIds& attributes );

    virtual bool changeAttributeValues( const QgsChangedAttributesMap & attr_map );

    virtual QVariant defaultValue( int fieldId );

    virtual bool changeGeometryValues( QgsGeometryMap & geometry_map );

    virtual bool createSpatialIndex();

    virtual int capabilities() const;

    QString capabilitiesString() const;

    virtual void setEncoding( const QString& e );

    QString encoding() const;

    int fieldNameIndex( const QString& fieldName ) const;

    QMap<QString, int> fieldNameMap() const;

    virtual QgsAttributeList attributeIndexes();

    const QgsNativeTypeMap &supportedNativeTypes() const;

    void enableGeometrylessFeatures( bool fetch );

  protected:
    QVariant convertValue( QVariant::Type type, QString value );

    void fillMinMaxCache();

    bool mCacheMinMaxDirty;
    QMap<int, QVariant> mCacheMinValues, mCacheMaxValues;

    QTextCodec* mEncoding;

    bool mFetchFeaturesWithoutGeom;

    bool mFetchGeom;

    QgsAttributeList mAttributesToFetch;

    QgsNativeTypeMap mSupportedNativeTypes;
};

#endif

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