C++ QgsVectorLayer::addFeature方法代码示例

void QgsMapToolOffsetCurve::canvasReleaseEvent( QMouseEvent * e )
{
  Q_UNUSED( e );
  QgsVectorLayer* vlayer = currentVectorLayer();
  if ( !vlayer )
  {
    deleteRubberBandAndGeometry();
    return;
  }

  if ( !mGeometryModified )
  {
    deleteRubberBandAndGeometry();
    vlayer->destroyEditCommand();
    return;
  }

  if ( mMultiPartGeometry )
  {
    mModifiedGeometry.convertToMultiType();
  }

  vlayer->beginEditCommand( tr( "Offset curve" ) );

  bool editOk;
  if ( mSourceLayerId == vlayer->id() && !mForceCopy )
  {
    editOk = vlayer->changeGeometry( mModifiedFeature, &mModifiedGeometry );
  }
  else
  {
    QgsFeature f;
    f.setGeometry( mModifiedGeometry );

    //add empty values for all fields (allows inserting attribute values via the feature form in the same session)
    QgsAttributes attrs( vlayer->pendingFields().count() );
    const QgsFields& fields = vlayer->pendingFields();
    for ( int idx = 0; idx < fields.count(); ++idx )
    {
      attrs[idx] = QVariant();
    }
    f.setAttributes( attrs );
    editOk = vlayer->addFeature( f );
  }

  if ( editOk )
  {
    vlayer->endEditCommand();
  }
  else
  {
    vlayer->destroyEditCommand();
  }

  deleteRubberBandAndGeometry();
  deleteDistanceItem();
  delete mSnapVertexMarker; mSnapVertexMarker = 0;
  mForceCopy = false;
  mCanvas->refresh();
}

QgsVectorLayer *QgsAuxiliaryLayer::toSpatialLayer() const
{
  QgsVectorLayer *layer = QgsMemoryProviderUtils::createMemoryLayer( QStringLiteral( "auxiliary_layer" ), fields(), mLayer->wkbType(), mLayer->crs() );

  QString pkField = mJoinInfo.targetFieldName();
  QgsFeature joinFeature;
  QgsFeature targetFeature;
  QgsFeatureIterator it = getFeatures();

  layer->startEditing();
  while ( it.nextFeature( joinFeature ) )
  {
    QString filter = QgsExpression::createFieldEqualityExpression( pkField, joinFeature.attribute( AS_JOINFIELD ) );

    QgsFeatureRequest request;
    request.setFilterExpression( filter );

    mLayer->getFeatures( request ).nextFeature( targetFeature );

    if ( targetFeature.isValid() )
    {
      QgsFeature newFeature( joinFeature );
      newFeature.setGeometry( targetFeature.geometry() );
      layer->addFeature( newFeature );
    }
  }
  layer->commitChanges();

  return layer;
}

static QgsVectorLayer* make_layer( const QStringList& wkts )
{
  QgsVectorLayer* vl = new QgsVectorLayer( "LineString", "x", "memory" );
  Q_ASSERT( vl->isValid() );

  vl->startEditing();
  Q_FOREACH ( const QString& wkt, wkts )
  {
    QgsFeature f( make_feature( wkt ) );
    vl->addFeature( f, false );
  }

void RgShortestPathWidget::exportPath()
{
  RgExportDlg dlg( this );
  if ( !dlg.exec() )
    return;

  QgsVectorLayer *vl = dlg.mapLayer();
  if ( vl == NULL )
    return;

  QgsPoint p1, p2;
  QgsGraph *path = getPath( p1, p2 );
  if ( path == NULL )
    return;

  QgsCoordinateTransform ct( mPlugin->iface()->mapCanvas()->mapRenderer()->destinationCrs(),
                             vl->crs() );

  int startVertexIdx = path->findVertex( p1 );
  int stopVertexIdx  = path->findVertex( p2 );

  QgsPolyline p;
  while ( startVertexIdx != stopVertexIdx )
  {
    QgsGraphArcIdList l = path->vertex( stopVertexIdx ).inArc();
    if ( l.empty() )
      break;
    const QgsGraphArc& e = path->arc( l.front() );
    p.push_front( ct.transform( path->vertex( e.inVertex() ).point() ) );
    stopVertexIdx = e.outVertex();
  }
  p.push_front( ct.transform( p1 ) );

  vl->startEditing();
  QgsFeature f;
  f.setGeometry( QgsGeometry::fromPolyline( p ) );
  vl->addFeature( f );
  vl->updateExtents();

  mPlugin->iface()->mapCanvas()->update();
  delete path;
}

//.........这里部分代码省略.........

    closePolygon();

    vlayer->beginEditCommand( tr( "Ring added and filled" ) );
    QList< QgsPoint > pointList = points();

    QgsFeatureId modifiedFid;
    int addRingReturnCode = vlayer->addRing( pointList, &modifiedFid );
    if ( addRingReturnCode != 0 )
    {
      QString errorMessage;
      //todo: open message box to communicate errors
      if ( addRingReturnCode == 1 )
      {
        errorMessage = tr( "a problem with geometry type occured" );
      }
      else if ( addRingReturnCode == 2 )
      {
        errorMessage = tr( "the inserted Ring is not closed" );
      }
      else if ( addRingReturnCode == 3 )
      {
        errorMessage = tr( "the inserted Ring is not a valid geometry" );
      }
      else if ( addRingReturnCode == 4 )
      {
        errorMessage = tr( "the inserted Ring crosses existing rings" );
      }
      else if ( addRingReturnCode == 5 )
      {
        errorMessage = tr( "the inserted Ring is not contained in a feature" );
      }
      else
      {
        errorMessage = tr( "an unknown error occured" );
      }
      emit messageEmitted( tr( "could not add ring since %1." ).arg( errorMessage ), QgsMessageBar::CRITICAL );
      vlayer->destroyEditCommand();
    }
    else
    {
      // find parent feature and get it attributes
      double xMin, xMax, yMin, yMax;
      QgsRectangle bBox;

      xMin = std::numeric_limits<double>::max();
      xMax = -std::numeric_limits<double>::max();
      yMin = std::numeric_limits<double>::max();
      yMax = -std::numeric_limits<double>::max();

      Q_FOREACH ( const QgsPoint& point, pointList )
      {
        xMin = qMin( xMin, point.x() );
        xMax = qMax( xMax, point.x() );
        yMin = qMin( yMin, point.y() );
        yMax = qMax( yMax, point.y() );
      }

      bBox.setXMinimum( xMin );
      bBox.setYMinimum( yMin );
      bBox.setXMaximum( xMax );
      bBox.setYMaximum( yMax );

      QgsFeatureIterator fit = vlayer->getFeatures( QgsFeatureRequest().setFilterFid( modifiedFid ) );

      QgsFeature f;
      bool res = false;
      if ( fit.nextFeature( f ) )
      {
        //create QgsFeature with wkb representation
        QgsFeature* ft = new QgsFeature( vlayer->fields(), 0 );

        ft->setGeometry( QgsGeometry::fromPolygon( QgsPolygon() << pointList.toVector() ) );
        ft->setAttributes( f.attributes() );

        if ( QApplication::keyboardModifiers() == Qt::ControlModifier )
        {
          res = vlayer->addFeature( *ft );
        }
        else
        {
          QgsAttributeDialog *dialog = new QgsAttributeDialog( vlayer, ft, false, NULL, true );
          dialog->setIsAddDialog( true );
          res = dialog->exec(); // will also add the feature
        }

        if ( res )
        {
          vlayer->endEditCommand();
        }
        else
        {
          delete ft;
          vlayer->destroyEditCommand();
        }
        res = false;
      }
    }
    stopCapturing();
  }

//.........这里部分代码省略.........
        errorMessage = tr( "A problem with geometry type occured" );
      }
      else if ( addRingReturnCode == 2 )
      {
        errorMessage = tr( "The inserted Ring is not closed" );
      }
      else if ( addRingReturnCode == 3 )
      {
        errorMessage = tr( "The inserted Ring is not a valid geometry" );
      }
      else if ( addRingReturnCode == 4 )
      {
        errorMessage = tr( "The inserted Ring crosses existing rings" );
      }
      else if ( addRingReturnCode == 5 )
      {
        errorMessage = tr( "The inserted Ring is not contained in a feature" );
      }
      else
      {
        errorMessage = tr( "An unknown error occured" );
      }
      QMessageBox::critical( 0, tr( "Error, could not add ring" ), errorMessage );
      vlayer->destroyEditCommand();
    }
    else
    {
      // find parent feature and get it attributes
      double xMin, xMax, yMin, yMax;
      QgsRectangle bBox;

      xMin = std::numeric_limits<double>::max();
      xMax = -std::numeric_limits<double>::max();
      yMin = std::numeric_limits<double>::max();
      yMax = -std::numeric_limits<double>::max();

      for ( QList<QgsPoint>::const_iterator it = points().constBegin(); it != points().constEnd(); ++it )
      {
        if ( it->x() < xMin )
        {
          xMin = it->x();
        }
        if ( it->x() > xMax )
        {
          xMax = it->x();
        }
        if ( it->y() < yMin )
        {
          yMin = it->y();
        }
        if ( it->y() > yMax )
        {
          yMax = it->y();
        }
      }
      bBox.setXMinimum( xMin );
      bBox.setYMinimum( yMin );
      bBox.setXMaximum( xMax );
      bBox.setYMaximum( yMax );

      QgsFeatureIterator fit = vlayer->getFeatures( QgsFeatureRequest().setFilterRect( bBox ).setFlags( QgsFeatureRequest::ExactIntersect ) );

      QgsFeature f;
      bool res = false;
      while ( fit.nextFeature( f ) )
      {
        //create QgsFeature with wkb representation
        QgsFeature* ft = new QgsFeature( vlayer->pendingFields(),  0 );

        QgsGeometry *g;
        g = QgsGeometry::fromPolygon( QgsPolygon() << points().toVector() );
        ft->setGeometry( g );
        ft->setAttributes( f.attributes() );

        if ( QgsApplication::keyboardModifiers() == Qt::ControlModifier )
        {
          res = vlayer->addFeature( *ft );
        }
        else
        {
          QgsAttributeDialog *dialog = new QgsAttributeDialog( vlayer, ft, false, NULL, true );
          dialog->setIsAddDialog( true );
          res = dialog->exec(); // will also add the feature
        }

        if ( res )
        {
          vlayer->endEditCommand();
        }
        else
        {
          delete ft;
          vlayer->destroyEditCommand();
        }
        res = false;
      }
    }
    stopCapturing();
  }
}

//.........这里部分代码省略.........
    // add new layer
    QgsVectorLayer* newLayer = new QgsVectorLayer( QString( "dbname='%1' table='%2'(Geometry) sql=" )
        .arg( offlineDbPath ).arg( tableName ), tableName + " (offline)", "spatialite" );
    if ( newLayer->isValid() )
    {
      // mark as offline layer
      newLayer->setCustomProperty( CUSTOM_PROPERTY_IS_OFFLINE_EDITABLE, true );

      // store original layer source
      newLayer->setCustomProperty( CUSTOM_PROPERTY_REMOTE_SOURCE, layer->source() );
      newLayer->setCustomProperty( CUSTOM_PROPERTY_REMOTE_PROVIDER, layer->providerType() );

      // copy style
      bool hasLabels = layer->hasLabelsEnabled();
      if ( !hasLabels )
      {
        // NOTE: copy symbology before adding the layer so it is displayed correctly
        copySymbology( layer, newLayer );
      }

      // register this layer with the central layers registry
      QgsMapLayerRegistry::instance()->addMapLayers(
        QList<QgsMapLayer *>() << newLayer );

      if ( hasLabels )
      {
        // NOTE: copy symbology of layers with labels enabled after adding to project, as it will crash otherwise (WORKAROUND)
        copySymbology( layer, newLayer );
      }

      // TODO: layer order

      // copy features
      newLayer->startEditing();
      QgsFeature f;

      // NOTE: force feature recount for PostGIS layer, else only visible features are counted, before iterating over all features (WORKAROUND)
      layer->setSubsetString( "" );

      QgsFeatureIterator fit = layer->getFeatures();

      emit progressModeSet( QgsOfflineEditing::CopyFeatures, layer->featureCount() );
      int featureCount = 1;

      QList<QgsFeatureId> remoteFeatureIds;
      while ( fit.nextFeature( f ) )
      {
        remoteFeatureIds << f.id();

        // NOTE: Spatialite provider ignores position of geometry column
        // fill gap in QgsAttributeMap if geometry column is not last (WORKAROUND)
        int column = 0;
        QgsAttributes attrs = f.attributes();
        QgsAttributes newAttrs( attrs.count() );
        for ( int it = 0; it < attrs.count(); ++it )
        {
          newAttrs[column++] = attrs[it];
        }
        f.setAttributes( newAttrs );

        newLayer->addFeature( f, false );

        emit progressUpdated( featureCount++ );
      }
      if ( newLayer->commitChanges() )
      {
        emit progressModeSet( QgsOfflineEditing::ProcessFeatures, layer->featureCount() );
        featureCount = 1;

        // update feature id lookup
        int layerId = getOrCreateLayerId( db, newLayer->id() );
        QList<QgsFeatureId> offlineFeatureIds;

        QgsFeatureIterator fit = newLayer->getFeatures( QgsFeatureRequest().setFlags( QgsFeatureRequest::NoGeometry ).setSubsetOfAttributes( QgsAttributeList() ) );
        while ( fit.nextFeature( f ) )
        {
          offlineFeatureIds << f.id();
        }

        // NOTE: insert fids in this loop, as the db is locked during newLayer->nextFeature()
        sqlExec( db, "BEGIN" );
        int remoteCount = remoteFeatureIds.size();
        for ( int i = 0; i < remoteCount; i++ )
        {
          addFidLookup( db, layerId, offlineFeatureIds.at( i ), remoteFeatureIds.at( remoteCount - ( i + 1 ) ) );
          emit progressUpdated( featureCount++ );
        }
        sqlExec( db, "COMMIT" );
      }
      else
      {
        showWarning( newLayer->commitErrors().join( "\n" ) );
      }

      // remove remote layer
      QgsMapLayerRegistry::instance()->removeMapLayers(
        QStringList() << layer->id() );
    }
  }
}

void QgsMapToolOffsetCurve::applyOffset()
{
  QgsVectorLayer* layer = currentVectorLayer();
  if ( !layer )
  {
    deleteRubberBandAndGeometry();
    notifyNotVectorLayer();
    return;
  }

  // no modification
  if ( !mGeometryModified )
  {
    deleteRubberBandAndGeometry();
    layer->destroyEditCommand();
    deleteDistanceWidget();
    return;
  }

  if ( mMultiPartGeometry )
  {
    mModifiedGeometry.convertToMultiType();
  }

  layer->beginEditCommand( tr( "Offset curve" ) );

  bool editOk;
  if ( mSourceLayerId == layer->id() && !mForceCopy )
  {
    editOk = layer->changeGeometry( mModifiedFeature, &mModifiedGeometry );
  }
  else
  {
    QgsFeature f;
    f.setGeometry( mModifiedGeometry );

    //add empty values for all fields (allows inserting attribute values via the feature form in the same session)
    QgsAttributes attrs( layer->fields().count() );
    const QgsFields& fields = layer->fields();
    for ( int idx = 0; idx < fields.count(); ++idx )
    {
      attrs[idx] = QVariant();
    }
    f.setAttributes( attrs );
    editOk = layer->addFeature( f );
  }

  if ( editOk )
  {
    layer->endEditCommand();
  }
  else
  {
    layer->destroyEditCommand();
  }

  deleteRubberBandAndGeometry();
  deleteDistanceWidget();
  delete mSnapVertexMarker;
  mSnapVertexMarker = nullptr;
  mForceCopy = false;
  mCanvas->refresh();
}