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  //reenable wfs with extent setting: pass canvas info to source select

  wfss->setProperty( "MapExtent", mMapCanvas->extent().toString() );

  if ( mMapCanvas->mapRenderer()->hasCrsTransformEnabled() )

  { //if "on the fly" reprojection is active, pass canvas CRS

    wfss->setProperty( "MapCRS", mMapCanvas->mapRenderer()->destinationCrs().authid() );

  }

    progressDialog = new QProgressDialog( tr( "Loading WFS data\n%1" ).arg( mTypeName ), tr( "Abort" ), 0, 0, mainWindow );

#include "qgis.h"

#include "qgsmaplayerregistry.h"

    mGeometryAttribute( 0 ),

    mWKBType( QGis::WKBUnknown ),

    mValid( true ),

    mLayer( 0 ),

    mGetRenderedOnly( false ),

    mInitGro( false ),

    mGetExtent()

  //Local url or HTTP?  [WBC 111221] refactored from getFeature()

  if ( uri.startsWith( "http" ) )

  {

    mEncoding = QgsWFSProvider::GET;

  }

  else

  {

    mEncoding = QgsWFSProvider::FILE;

  }

  //create mSourceCRS from url if possible [WBC 111221] refactored from GetFeatureGET()

  QString srsname = parameterFromUrl( "SRSNAME" );

  if ( !srsname.isEmpty() )

  {

    mSourceCRS.createFromOgcWmsCrs( srsname );

  }

  //fetch attributes of layer and type of its geometry attribute

  //WBC 111221: extracting geometry type here instead of getFeature allows successful

  //layer creation even when no features are retrieved (due to, e.g., BBOX or FILTER)

  if ( describeFeatureType( uri, mGeometryAttribute, mFields, mWKBType ) )

  {

    mValid = false;

    QgsDebugMsg( QString( "describeFeatureType failed, URI=%1" ).arg( uri ) );

    QMessageBox( QMessageBox::Warning, "DescribeFeatureType failed!",

                 QString( "Layer cannot be created from\n%1" ).arg( uri ) );

    return;

  }

  if ( ! uri.contains("BBOX") )

  { //"Cache Features" option; get all features in layer immediately

    reloadData();

  } //otherwise, defer feature retrieval until layer is first rendered

  if ( rect.isEmpty() )

  { //select all features

    mSpatialFilter = mExtent;

  { //select features intersecting caller's extent

    QString dsURI = dataSourceUri();

    //first time through, initialize GetRenderedOnly args

    //ctor cannot initialize because layer object not available then

    if ( ! mInitGro )

    { //did user check "Cache Features" in WFS layer source selection?

      if ( dsURI.contains( "BBOX" ) )

      { //no: initialize incremental getFeature

        if ( initGetRenderedOnly( rect ) )

        {

          mGetRenderedOnly = true;

        }

        else

        { //initialization failed;

          QgsDebugMsg( QString( "GetRenderedOnly initialization failed; incorrect operation may occur\n%1" )

                                .arg( dataSourceUri() ) );

          QMessageBox( QMessageBox::Warning, "Non-Cached layer initialization failed!",

                       QString( "Incorrect operation may occur:\n%1" ).arg( dataSourceUri() ) );

        }

      }

      mInitGro = true;

    }

    if ( mGetRenderedOnly )

    { //"Cache Features" was not selected for this layer

      //has rendered extent expanded beyond last-retrieved WFS extent?

      //NB: "intersect" instead of "contains" tolerates rounding errors;

      //    avoids unnecessary second fetch on zoom-in/zoom-out sequences

      QgsRectangle olap( rect );

      olap = olap.intersect( &mGetExtent );

      if ( doubleNear( rect.width(), olap.width() ) && doubleNear ( rect.height(), olap.height() ) )

      { //difference between canvas and layer extents is within rounding error: do not re-fetch

        QgsDebugMsg( QString( "Layer %1 GetRenderedOnly: no fetch required" ).arg( mLayer->name() ) );

      }

      else

      { //combined old and new extents might speed up local panning & zooming

        mGetExtent.combineExtentWith( &rect );

        //but see if the combination is useless or too big

        double pArea = mGetExtent.width() * mGetExtent.height();

        double cArea = rect.width() * rect.height();

        if ( olap.isEmpty() || pArea > ( cArea * 4.0 ) )

        { //new canvas extent does not overlap or combining old and new extents would

          //fetch > 4 times the area to be rendered; get only what will be rendered

          mGetExtent = rect;

        }

        QgsDebugMsg( QString( "Layer %1 GetRenderedOnly: fetching extent %2" )

                   .arg( mLayer->name(), mGetExtent.asWktCoordinates() ) );

        dsURI = dsURI.replace( QRegExp( "BBOX=[^&]*" ),

                               QString( "BBOX=%1,%2,%3,%4" )

                               .arg( mGetExtent.xMinimum(), 0, 'f' )

                               .arg( mGetExtent.yMinimum(), 0, 'f' )

                               .arg( mGetExtent.xMaximum(), 0, 'f' )

                               .arg( mGetExtent.yMaximum(), 0, 'f' ) );

        //TODO: BBOX may not be combined with FILTER. WFS spec v. 1.1.0, sec. 14.7.3 ff.

        //      if a FILTER is present, the BBOX must be merged into it, capabilities permitting.

        //      Else one criterion must be abandoned and the user warned.  [WBC 111221]

        setDataSourceUri( dsURI );

        reloadData();

        mLayer->updateExtents();

      }

    mSpatialFilter = rect;

    mSelectedFeatures = mSpatialIndex->intersects( mSpatialFilter );

  else  //local file

int QgsWFSProvider::describeFeatureType( const QString& uri, QString& geometryAttribute,

                                         QgsFieldMap& fields, QGis::WkbType& geomType )

//NB: also called from QgsWFSSourceSelect::on_treeWidget_itemDoubleClicked() to build filters.

//    a temporary provider object is constructed with a null URI, which bypasses much provider

//    instantiation logic: refresh(), getFeature(), etc.  therefore, many provider class members

//    are only default values or uninitialized when running under the source select dialog!

  //Local url or HTTP?  WBC111221 refactored here from getFeature()

  switch( mEncoding )

  {

     case QgsWFSProvider::GET:

     {

       return describeFeatureTypeGET( uri, geometryAttribute, fields, geomType );

     }

     case QgsWFSProvider::FILE:

     {

       return describeFeatureTypeFile( uri, geometryAttribute, fields, geomType );

     }

  }

  QgsDebugMsg( "SHOULD NOT OCCUR: mEncoding undefined" );

int QgsWFSProvider::describeFeatureTypeGET( const QString& uri, QString& geometryAttribute, QgsFieldMap& fields, QGis::WkbType& geomType )

  QString describeFeatureUri = uri;

  describeFeatureUri.replace( QString( "GetFeature" ), QString( "DescribeFeatureType" ) );

  QNetworkRequest request( describeFeatureUri );

  if ( readAttributesFromSchema( describeFeatureDocument,

                                 geometryAttribute, fields, geomType ) != 0 )

    QgsDebugMsg( QString( "FAILED: readAttributesFromSchema" ) );

int QgsWFSProvider::describeFeatureTypeFile( const QString& uri, QString& geometryAttribute, QgsFieldMap& fields, QGis::WkbType& geomType)

    if ( readAttributesFromSchema( schemaDoc, geometryAttribute, fields, geomType ) != 0 )

int QgsWFSProvider::readAttributesFromSchema( QDomDocument& schemaDoc, QString& geometryAttribute, QgsFieldMap& fields, QGis::WkbType& geomType )

    QRegExp gmlPT( "gml:(.*)PropertyType" );

    if ( type.indexOf( gmlPT ) == 0 || name.isEmpty() )

      geomType = geomTypeFromPropertyType(geometryAttribute, gmlPT.cap(1) );

//initialization for getRenderedOnly option

//(formerly "Only request features overlapping the current view extent")

bool QgsWFSProvider::initGetRenderedOnly( const QgsRectangle rect )

{ //find our layer

  QMap<QString, QgsMapLayer*> layers = QgsMapLayerRegistry::instance()->mapLayers();

  QMap<QString, QgsMapLayer*>::const_iterator layersIt = layers.begin();

  for ( ; layersIt != layers.end() ; ++layersIt )

  {

    if ( ( mLayer = dynamic_cast<QgsVectorLayer*>( layersIt.value() ) ) )

    {

      if ( mLayer->dataProvider() == this )

      {

        QgsDebugMsg( QString( "found layer %1" ).arg( mLayer->name() ) );

        break;

      }

    }

  }

  if ( layersIt == layers.end() )

  {

    QgsDebugMsg( "SHOULD NOT OCCUR: initialize() did not find layer." );

    return false;

  }

  return true;

}

QGis::WkbType QgsWFSProvider::geomTypeFromPropertyType( QString attName, QString propType )

{

  const QStringList geomTypes = ( QStringList ()

    //all GML v.2.1.3 _geometryProperty group members, except MultiGeometryPropertyType

    //sequence must exactly match enum Qgis::WkbType

    << ""  // unknown geometry, enum 0

    << "Point"

    << "LineString"

    << "Polygon"

    << "MultiPoint"

    << "MultiLineString"

    << "MultiPolygon" );

  QgsDebugMsg( QString( "DescribeFeatureType geometry attribute \"%1\" type is \"%2\"" )

                       .arg( attName, propType ) );

  int i = geomTypes.indexOf( propType );

  if ( i <= 0 )

  { // feature type missing or unknown

    i = (int) QGis::WKBUnknown;

  }

  return (QGis::WkbType) i;

}

#include "qgsmaplayer.h"

#include "qgsvectorlayer.h"

    /**Collects information about the field types. Is called internally from QgsWFSProvider ctor. The method delegates the work to request specific ones and gives back the name of the geometry attribute and the thematic attributes with their types*/

    int describeFeatureType( const QString& uri, QString& geometryAttribute,

                             QgsFieldMap& fields, QGis::WkbType& geomType );

    /**GetRenderedOnly: layer asociated with this provider*/

    QgsVectorLayer *mLayer;

    /**GetRenderedOnly: fetch only features within canvas extent to be rendered*/

    bool mGetRenderedOnly;

    /**GetRenderedOnly initializaiton flat*/

    bool mInitGro;

    /**if GetRenderedOnly, extent specified in WFS getFeatures; else empty (no constraint)*/

    QgsRectangle mGetExtent;

    int describeFeatureTypeGET( const QString& uri, QString& geometryAttribute, QgsFieldMap& fields, QGis::WkbType& geomType );

    int describeFeatureTypeFile( const QString& uri, QString& geometryAttribute, QgsFieldMap& fields, QGis::WkbType& geomType );

    int readAttributesFromSchema( QDomDocument& schemaDoc, QString& geometryAttribute, QgsFieldMap& fields, QGis::WkbType& geomType );

    /**Initializes "Cache Features" inactive processing*/

    bool initGetRenderedOnly( QgsRectangle );

    /**Converts DescribeFeatureType schema geometry property type to WKBType*/

    QGis::WkbType geomTypeFromPropertyType( QString attName, QString propType );

#include "qgscoordinatetransform.h"

  QgsWFSConnection conn( cmbConnections->currentText() );

  QString pCrsString( labelCoordRefSys->text() );

  QgsCoordinateReferenceSystem pCrs( pCrsString );

  //prepare canvas extent info for layers with "cache features" option not set

  QgsRectangle extent;

  QVariant extentVariant = property( "MapExtent" );

  if ( extentVariant.isValid() )

    QString crs;

    QgsCoordinateTransform xform;

    QString extentString = extentVariant.toString();

    QStringList minMaxSplit = extentString.split( ":" );

    if ( minMaxSplit.size() > 1 )

      QStringList xyMinSplit = minMaxSplit[0].split( "," );

      QStringList xyMaxSplit = minMaxSplit[1].split( "," );

      if ( xyMinSplit.size() > 1 && xyMaxSplit.size() > 1 )

      {

        extent.set( xyMinSplit[0].toDouble(), xyMinSplit[1].toDouble(),

                    xyMaxSplit[0].toDouble(), xyMaxSplit[1].toDouble() );

      }

    }

    //does canvas have "on the fly" reprojection set?

    QVariant crsVariant = property( "MapCRS" );

    if ( crsVariant.isValid() )

    { //transform between provider CRS set in source select dialog and canvas CRS

      QgsCoordinateReferenceSystem cCrs( crsVariant.toString() );

      if ( pCrs.isValid() && cCrs.isValid() )

      {

        QgsCoordinateTransform xform( pCrs, cCrs );

        extent = xform.transformBoundingBox( extent, QgsCoordinateTransform::ReverseTransform );

        QgsDebugMsg( QString("canvas transform: Canvas CRS=%1, Provider CRS=%2, BBOX=%3")

                             .arg(cCrs.authid(), pCrs.authid(), extent.asWktCoordinates() ) );

      }

  }

  //create layers that user selected from this WFS source

  for ( ; sIt != selectedItems.constEnd(); ++sIt )

  { //add a wfs layer to the map

    QString typeName = ( *sIt )->text( 1 );  //WFS repository's name for layer

    QString filter = ( *sIt )->text( 4 );    //optional filter specified by user

    //is "cache features" checked?

    if ( ( *sIt )->checkState( 3 ) == Qt::Checked )

    { //yes: entire WFS layer will be retrieved and cached

      mUri = conn.uriGetFeature( typeName, pCrsString, filter );

    }

    else

    { //no: include BBOX of current canvas extent in URI

      mUri = conn.uriGetFeature( typeName, pCrsString, filter, extent );

    }

    emit addWfsLayer( mUri, typeName );

    QgsWFSProvider p( "" );  //bypasses most provider instantiation logic

    QGis::WkbType geomType;

    if ( p.describeFeatureType( uri, geometryAttribute, fields, geomType ) != 0 )

    QString mUri;            // data source URI

    <width>592</width>

     <attribute name="headerMinimumSectionSize">

      <number>27</number>

     </attribute>

     <attribute name="headerMinimumSectionSize">

      <number>27</number>

     </attribute>

       <string>Cache

Features</string>

      </property>

      <property name="textAlignment">

       <set>AlignHCenter|AlignVCenter|AlignCenter</set>