qgsgpxprovider.h

一个非常好的GIS开源新版本

/***************************************************************************
      qgsgpxprovider.h  -  Data provider for GPS eXchange files
                             -------------------
    begin                : 2004-04-14
    copyright            : (C) 2004 by Lars Luthman
    email                : [e-mail]

    Partly based on qgsdelimitedtextprovider.h, (C) 2004 Gary E. Sherman
 ***************************************************************************/

/***************************************************************************
 *                                                                         *
 *   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.                                   *
 *                                                                         *
 ***************************************************************************/


#include "qgsvectordataprovider.h"
#include "gpsdata.h"


class QgsFeature;
class QgsField;
class QFile;
class QDomDocument;
class GPSData;


/**
\class QgsGPXProvider
\brief Data provider for GPX (GPS eXchange) files
* This provider adds the ability to load GPX files as vector layers.
* 
*/
class QgsGPXProvider : public QgsVectorDataProvider
{
  
public:
  
  QgsGPXProvider(QString uri = QString());
  virtual ~QgsGPXProvider();
  
  /* Functions inherited from 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(QgsAttributeList fetchAttributes = QgsAttributeList(),
                      QgsRect rect = QgsRect(),
                      bool fetchGeometry = true,
                      bool useIntersect = false);

  /**
   * 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);
  
  /**
   * Get feature type.
   * @return int representing the feature type
   */
  virtual QGis::WKBTYPE geometryType() const;

  /**
   * Number of features in the layer
   * @return long containing number of features
   */
  virtual long featureCount() const;
    
  /** 
   * Get the number of fields in the layer
   */
  virtual uint fieldCount() const;

  /**
   * Get the field information for the layer
   */
  virtual const QgsFieldMap & fields() const;
  
  /** Restart reading features from previous select operation */
  virtual void reset();
    
  /**
   * Adds a list of features
   * @return true in case of success and false in case of failure
   */
  virtual bool addFeatures(QgsFeatureList & flist);

  /** 
   * 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 QgsFeatureIds & id);
  
  /**
   * 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 QgsChangedAttributesMap & attr_map);
  
  virtual int capabilities() const;
  
  /**
   * Returns the default value for field specified by @c fieldId
   */
  virtual QVariant getDefaultValue(int fieldId);
  
  
  /* Functions inherited from QgsDataProvider */
  
  /** Return the extent for this data layer
   */
  virtual QgsRect extent();
  
  /**Returns true if this is a valid delimited file
   */
  virtual bool isValid();

  /** return a provider name */
  virtual QString name() const;

  /** return description */
  virtual QString description() const;

  virtual QgsSpatialRefSys getSRS();
  
  
  /* new functions */

  void changeAttributeValues(GPSObject& obj, 
                             const QgsAttributeMap& attrs);
  
  /** Adds one feature (used by addFeatures()) */
  bool addFeature(QgsFeature& f);
  
  /**
   * Check to see if the point is withn the selection
   * rectangle
   * @param x X value of point
   * @param y Y value of point
   * @return True if point is within the rectangle
   */
  bool boundsCheck(double x, double y);


private:
  
  GPSData* data;
  
  //! Fields
  QgsFieldMap attributeFields;
  
  QString mFileName;

  enum { WaypointType, RouteType, TrackType } mFeatureType;
  enum Attribute { NameAttr = 0, EleAttr, SymAttr, NumAttr, 
		   CmtAttr, DscAttr, SrcAttr, URLAttr, URLNameAttr };
  static const char* attr[];
  //! Current selection rectangle
  QgsRect *mSelectionRectangle;
  bool mValid;
  long mNumberFeatures;
  
  //! Current waypoint iterator
  GPSData::WaypointIterator mWptIter;
  //! Current route iterator
  GPSData::RouteIterator mRteIter;
  //! Current track iterator
  GPSData::TrackIterator mTrkIter;

  struct wkbPoint{
    char byteOrder;
    unsigned wkbType;
    double x;
    double y;
  };
  wkbPoint mWKBpt;
  
};