qgsfeature.h

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/***************************************************************************
                      qgsfeature.h - Spatial Feature Class
                     --------------------------------------
Date                 : 09-Sep-2003
Copyright            : (C) 2003 by Gary E.Sherman
email                : sherman at mrcc.com
 ***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/

#ifndef QGSFEATURE_H
#define QGSFEATURE_H

#include <QMap>
#include <QString>
#include <QVariant>
#include <QList>
#include <QHash>
#include <QVector>
#include <QSet>

class QgsGeometry;
class QgsRectangle;
class QgsFeature;
class QgsFields;
class QgsFeaturePrivate;

// feature id class (currently 64 bit)
#if 0
#include <limits>

class QgsFeatureId
{
  public:
    QgsFeatureId( qint64 id = 0 ) : mId( id ) {}
    QgsFeatureId( QString str ) : mId( str.toLongLong() ) {}
    QgsFeatureId &operator=( const QgsFeatureId &other ) { mId = other.mId; return *this; }
    QgsFeatureId &operator++() { mId++; return *this; }
    QgsFeatureId operator++( int ) { QgsFeatureId pId = mId; ++( *this ); return pId; }

    bool operator==( const QgsFeatureId &id ) const { return mId == id.mId; }
    bool operator!=( const QgsFeatureId &id ) const { return mId != id.mId; }
    bool operator<( const QgsFeatureId &id ) const { return mId < id.mId; }
    bool operator>( const QgsFeatureId &id ) const { return mId > id.mId; }
    operator QString() const { return QString::number( mId ); }

    bool isNew() const
    {
      return mId < 0;
    }

    qint64 toLongLong() const
    {
      return mId;
    }

  private:
    qint64 mId;

    friend uint qHash( const QgsFeatureId &id );
};

CORE_EXPORT QDataStream& operator<<( QDataStream& out, const QgsFeatureId& featureId );
CORE_EXPORT QDataStream& operator>>( QDataStream& in, QgsFeatureId& featureId );

inline uint qHash( const QgsFeatureId &id )
{
  return qHash( id.mId );
}

#define FID_IS_NEW(fid)     (fid).isNew()
#define FID_TO_NUMBER(fid)  (fid).toLongLong()
#define FID_TO_STRING(fid)  static_cast<QString>(fid)
#define STRING_TO_FID(str)  QgsFeatureId(str)
#endif

// 64 bit feature ids
#if 1
typedef qint64 QgsFeatureId;
#define FID_IS_NEW(fid)     (fid<0)
#define FID_TO_NUMBER(fid)  static_cast<qint64>(fid)
#define FID_TO_STRING(fid)  QString::number( fid )
#define STRING_TO_FID(str)  (str).toLongLong()
#endif

// 32 bit feature ids
#if 0
typedef int QgsFeatureId;
#define FID_IS_NEW(fid)     (fid<0)
#define FID_TO_NUMBER(fid)  static_cast<int>(fid)
#define FID_TO_STRING(fid)  QString::number( fid )
#define STRING_TO_FID(str)  (str).toLong()
#endif


// key = field index, value = field value
typedef QMap<int, QVariant> QgsAttributeMap;

/***************************************************************************
 * This class is considered CRITICAL and any change MUST be accompanied with
 * full unit tests in testqgsfeature.cpp.
 * See details in QEP #17
 ****************************************************************************/

class CORE_EXPORT QgsAttributes : public QVector<QVariant>
{
  public:
    QgsAttributes()
        : QVector<QVariant>()
    {}
    QgsAttributes( int size )
        : QVector<QVariant>( size )
    {}
    QgsAttributes( int size, const QVariant& v )
        : QVector<QVariant>( size, v )
    {}

    QgsAttributes( const QVector<QVariant>& v )
        : QVector<QVariant>( v )
    {}

    bool operator==( const QgsAttributes &v ) const
    {
      if ( size() != v.size() )
        return false;
      const QVariant* b = constData();
      const QVariant* i = b + size();
      const QVariant* j = v.constData() + size();
      while ( i != b )
        if ( !( *--i == *--j && i->isNull() == j->isNull() ) )
          return false;
      return true;
    }

    inline bool operator!=( const QgsAttributes &v ) const { return !( *this == v ); }
};

class QgsField;

#include "qgsfield.h"

/***************************************************************************
 * This class is considered CRITICAL and any change MUST be accompanied with
 * full unit tests in testqgsfeature.cpp.
 * See details in QEP #17
 ****************************************************************************/

class CORE_EXPORT QgsFeature
{
  public:

    QgsFeature( QgsFeatureId id = QgsFeatureId() );

    QgsFeature( const QgsFields& fields, QgsFeatureId id = QgsFeatureId() );

    QgsFeature( const QgsFeature & rhs );

    QgsFeature & operator=( QgsFeature const & rhs );

    virtual ~QgsFeature();

    QgsFeatureId id() const;

    void setFeatureId( QgsFeatureId id );

    QgsAttributes attributes() const;

    void setAttributes( const QgsAttributes& attrs );

    bool setAttribute( int field, const QVariant& attr );

    void initAttributes( int fieldCount );

    void deleteAttribute( int field );

    bool isValid() const;

    void setValid( bool validity );

    QgsGeometry* geometry();

    const QgsGeometry* constGeometry() const;

    Q_DECL_DEPRECATED QgsGeometry *geometryAndOwnership();

    void setGeometry( const QgsGeometry& geom );

    void setGeometry( QgsGeometry* geom );

    Q_DECL_DEPRECATED void setGeometryAndOwnership( unsigned char * geom, int length );

    Q_DECL_DEPRECATED void setFields( const QgsFields* fields, bool initAttributes = false );

    void setFields( const QgsFields& fields, bool initAttributes = false );

    const QgsFields* fields() const;

    bool setAttribute( const QString& name, const QVariant& value );

    bool deleteAttribute( const QString& name );

    QVariant attribute( const QString& name ) const;

    QVariant attribute( int fieldIdx ) const;

    int fieldNameIndex( const QString& fieldName ) const;

    operator QVariant() const
    {
      return QVariant::fromValue( *this );
    }

  private:

    QExplicitlySharedDataPointer<QgsFeaturePrivate> d;

}; // class QgsFeature

CORE_EXPORT QDataStream& operator<<( QDataStream& out, const QgsFeature& feature );
CORE_EXPORT QDataStream& operator>>( QDataStream& in, QgsFeature& feature );

// key = feature id, value = changed attributes
typedef QMap<QgsFeatureId, QgsAttributeMap> QgsChangedAttributesMap;

// key = feature id, value = changed geometry
typedef QMap<QgsFeatureId, QgsGeometry> QgsGeometryMap;

typedef QSet<QgsFeatureId> QgsFeatureIds;

// key = field index, value = field name
typedef QMap<int, QString> QgsFieldNameMap;

typedef QList<QgsFeature> QgsFeatureList;

Q_DECLARE_METATYPE( QgsFeature )
Q_DECLARE_METATYPE( QgsFeatureList )

#endif