C++ QgsVectorLayer类代码示例

RgExportDlg::RgExportDlg( QWidget* parent, Qt::WFlags fl )
    : QDialog( parent, fl )
{
  // create base widgets;
  setWindowTitle( tr( "Export feature" ) );
  QVBoxLayout *v = new QVBoxLayout( this );

  QHBoxLayout *h = new QHBoxLayout();
  QLabel *l = new QLabel( tr( "Select destination layer" ), this );
  h->addWidget( l );
  mcbLayers = new QComboBox( this );
  h->addWidget( mcbLayers );
  v->addLayout( h );

  QDialogButtonBox *bb = new QDialogButtonBox( QDialogButtonBox::Ok | QDialogButtonBox::Cancel, Qt::Horizontal, this );
  connect( bb, SIGNAL( accepted() ), this, SLOT( on_buttonBox_accepted() ) );
  connect( bb, SIGNAL( rejected() ), this, SLOT( on_buttonBox_rejected() ) );
  v->addWidget( bb );

  //fill list of layers
  mcbLayers->insertItem( 0, tr( "New temporary layer" ), QVariant( "-1" ) );

  QMap<QString, QgsMapLayer*> mapLayers = QgsMapLayerRegistry::instance()->mapLayers();
  QMap<QString, QgsMapLayer*>::iterator layer_it = mapLayers.begin();

  for ( ; layer_it != mapLayers.end(); ++layer_it )
  {
    QgsVectorLayer* vl = dynamic_cast<QgsVectorLayer*>( layer_it.value() );
    if ( !vl )
      continue;
    if ( vl->geometryType() != QGis::Line )
      continue;
    mcbLayers->insertItem( 0, vl->name(), QVariant( vl->id() ) );
  }

} // RgSettingsDlg::RgSettingsDlg()

void QgsComposerAttributeTableWidget::changeLayer( QgsMapLayer *layer )
{
  if ( !mComposerTable )
  {
    return;
  }

  QgsVectorLayer* vl = dynamic_cast<QgsVectorLayer*>( layer );
  if ( !vl )
  {
    return;
  }

  QgsComposition* composition = mComposerTable->composition();
  if ( composition )
  {
    composition->beginMultiFrameCommand( mComposerTable, tr( "Table layer changed" ) );
  }
  mComposerTable->setVectorLayer( vl );
  mComposerTable->update();
  if ( composition )
  {
    composition->endMultiFrameCommand();
  }

  if ( vl->geometryType() == QGis::NoGeometry )
  {
    //layer has no geometry, so uncheck & disable controls which require geometry
    mShowOnlyVisibleFeaturesCheckBox->setChecked( false );
    mShowOnlyVisibleFeaturesCheckBox->setEnabled( false );
  }
  else
  {
    mShowOnlyVisibleFeaturesCheckBox->setEnabled( true );
  }
}

void QgsVectorLayerJoinBuffer::cacheJoinLayer( QgsVectorJoinInfo& joinInfo )
{
  //memory cache not required or already done
  if ( !joinInfo.memoryCache || joinInfo.cachedAttributes.size() > 0 )
  {
    return;
  }

  QgsVectorLayer* cacheLayer = dynamic_cast<QgsVectorLayer*>( QgsMapLayerRegistry::instance()->mapLayer( joinInfo.joinLayerId ) );
  if ( cacheLayer )
  {
    int joinFieldIndex = cacheLayer->pendingFields().indexFromName( joinInfo.joinFieldName );

    joinInfo.cachedAttributes.clear();

    QgsFeatureIterator fit = cacheLayer->getFeatures( QgsFeatureRequest().setFlags( QgsFeatureRequest::NoGeometry ) );
    QgsFeature f;
    while ( fit.nextFeature( f ) )
    {
      const QgsAttributes& attrs = f.attributes();
      joinInfo.cachedAttributes.insert( attrs[joinFieldIndex].toString(), attrs );
    }
  }
}

void QgsComposerAttributeTableV2::resetColumns()
{
  QgsVectorLayer* source = sourceLayer();
  if ( !source )
  {
    return;
  }

  //remove existing columns
  qDeleteAll( mColumns );
  mColumns.clear();

  //rebuild columns list from vector layer fields
  int idx = 0;
  Q_FOREACH ( const QgsField& field, source->fields() )
  {
    QString currentAlias = source->attributeDisplayName( idx );
    QgsComposerTableColumn* col = new QgsComposerTableColumn;
    col->setAttribute( field.name() );
    col->setHeading( currentAlias );
    mColumns.append( col );
    idx++;
  }
}

void QgsServerProjectParser::addLayerProjectSettings( QDomElement& layerElem, QDomDocument& doc, QgsMapLayer* currentLayer ) const
{
  if ( !currentLayer )
  {
    return;
  }

  if ( currentLayer->type() == QgsMapLayer::VectorLayer )
  {
    QgsVectorLayer* vLayer = static_cast<QgsVectorLayer*>( currentLayer );
    const QSet<QString>& excludedAttributes = vLayer->excludeAttributesWMS();
    QString displayField = vLayer->displayField();

    //attributes
    QDomElement attributesElem = doc.createElement( "Attributes" );
    const QgsFields& layerFields = vLayer->pendingFields();
    for ( int idx = 0; idx < layerFields.count(); ++idx )
    {
      const QgsField& field = layerFields[idx];
      if ( excludedAttributes.contains( field.name() ) )
      {
        continue;
      }
      // field alias in case of displayField
      if ( field.name() == displayField )
      {
        displayField = vLayer->attributeDisplayName( idx );
      }
      QDomElement attributeElem = doc.createElement( "Attribute" );
      attributeElem.setAttribute( "name", field.name() );
      attributeElem.setAttribute( "type", QVariant::typeToName( field.type() ) );
      attributeElem.setAttribute( "typeName", field.typeName() );
      QString alias = vLayer->attributeAlias( idx );
      if ( !alias.isEmpty() )
      {
        attributeElem.setAttribute( "alias", alias );
      }

      //edit type to text
      attributeElem.setAttribute( "editType", vLayer->editorWidgetV2( idx ) );
      attributeElem.setAttribute( "comment", field.comment() );
      attributeElem.setAttribute( "length", field.length() );
      attributeElem.setAttribute( "precision", field.precision() );
      attributesElem.appendChild( attributeElem );
    }
    //displayfield
    layerElem.setAttribute( "displayField", displayField );
    layerElem.appendChild( attributesElem );
  }
}

int QgsSymbol::readFieldName( QDomNode &synode, QString name, const QgsVectorLayer &vl )
{
  QDomNode node = synode.namedItem( name + "name" );

  if ( !node.isNull() )
  {
    const QgsFieldMap &fields = vl.pendingFields();
    QString name = node.toElement().text();

    for ( QgsFieldMap::const_iterator it = fields.begin(); it != fields.end(); it++ )
      if ( it->name() == name )
        return it.key();

    return -1;
  }

  node = synode.namedItem( name );

  return node.isNull() ? -1 : node.toElement().text().toInt();
}

void QgsSymbolLegendNode::toggleAllItems()
{
  QgsVectorLayer *vlayer = qobject_cast<QgsVectorLayer *>( mLayerNode->layer() );
  if ( !vlayer || !vlayer->renderer() )
    return;

  const QgsLegendSymbolList symbolList = vlayer->renderer()->legendSymbolItems();
  for ( const auto &item : symbolList )
  {
    vlayer->renderer()->checkLegendSymbolItem( item.ruleKey(), ! vlayer->renderer()->legendSymbolItemChecked( item.ruleKey() ) );
  }

  emit dataChanged();
  vlayer->triggerRepaint();
}

bool QgsMapLayerProxyModel::filterAcceptsRow( int source_row, const QModelIndex &source_parent ) const
{
  if ( mFilters.testFlag( All ) && mExceptList.isEmpty() )
    return true;

  QModelIndex index = sourceModel()->index( source_row, 0, source_parent );
  QgsMapLayer* layer = static_cast<QgsMapLayer*>( index.internalPointer() );
  if ( !layer )
    return false;

  if ( mExceptList.contains( layer ) )
    return false;

  // layer type
  if (( mFilters.testFlag( RasterLayer ) && layer->type() == QgsMapLayer::RasterLayer ) ||
      ( mFilters.testFlag( VectorLayer ) && layer->type() == QgsMapLayer::VectorLayer ) ||
      ( mFilters.testFlag( PluginLayer ) && layer->type() == QgsMapLayer::PluginLayer ) )
    return true;

  // geometry type
  bool detectGeometry = mFilters.testFlag( NoGeometry ) ||
                        mFilters.testFlag( PointLayer ) ||
                        mFilters.testFlag( LineLayer ) ||
                        mFilters.testFlag( PolygonLayer ) ||
                        mFilters.testFlag( HasGeometry );
  if ( detectGeometry && layer->type() == QgsMapLayer::VectorLayer )
  {
    QgsVectorLayer* vl = dynamic_cast<QgsVectorLayer*>( layer );
    if ( vl )
    {
      if ( mFilters.testFlag( HasGeometry ) && vl->hasGeometryType() )
        return true;
      if ( mFilters.testFlag( NoGeometry ) && vl->geometryType() == QGis::NoGeometry )
        return true;
      if ( mFilters.testFlag( PointLayer ) && vl->geometryType() == QGis::Point )
        return true;
      if ( mFilters.testFlag( LineLayer ) && vl->geometryType() == QGis::Line )
        return true;
      if ( mFilters.testFlag( PolygonLayer ) && vl->geometryType() == QGis::Polygon )
        return true;
    }
  }

  return false;
}

int QgsMapToolCapture::fetchLayerPoint( const QgsPointLocator::Match &match, QgsPoint &layerPoint )
{
  QgsVectorLayer *vlayer = qobject_cast<QgsVectorLayer *>( mCanvas->currentLayer() );
  QgsVectorLayer *sourceLayer = match.layer();
  if ( match.isValid() && match.hasVertex() && sourceLayer &&
       ( sourceLayer->crs() == vlayer->crs() ) )
  {
    QgsFeature f;
    QgsFeatureRequest request;
    request.setFilterFid( match.featureId() );
    bool fetched = match.layer()->getFeatures( request ).nextFeature( f );
    if ( fetched )
    {
      QgsVertexId vId;
      if ( !f.geometry().vertexIdFromVertexNr( match.vertexIndex(), vId ) )
        return 2;

      layerPoint = f.geometry().constGet()->vertexAt( vId );

      // ZM support depends on the target layer
      if ( !QgsWkbTypes::hasZ( vlayer->wkbType() ) )
      {
        layerPoint.dropZValue();
      }

      if ( !QgsWkbTypes::hasM( vlayer->wkbType() ) )
      {
        layerPoint.dropMValue();
      }

      return 0;
    }
    else
    {
      return 2;
    }
  }
  else
  {
    return 1;
  }
}

bool QgsMapToolLabel::createAuxiliaryFields( LabelDetails &details, QgsPalIndexes &indexes ) const
{
  bool newAuxiliaryLayer = false;
  QgsVectorLayer *vlayer = details.layer;
  QString providerId = details.pos.providerID;

  if ( !vlayer || !vlayer->labelsEnabled() )
    return false;

  if ( !vlayer->auxiliaryLayer() )
  {
    QgsNewAuxiliaryLayerDialog dlg( vlayer );
    dlg.exec();
    newAuxiliaryLayer = true;
  }

  if ( !vlayer->auxiliaryLayer() )
    return false;

  for ( const QgsPalLayerSettings::Property &p : qgis::as_const( mPalProperties ) )
  {
    int index = -1;

    // always use the default activated property
    QgsProperty prop = details.settings.dataDefinedProperties().property( p );
    if ( prop.propertyType() == QgsProperty::FieldBasedProperty && prop.isActive() )
    {
      index = vlayer->fields().lookupField( prop.field() );
    }
    else
    {
      index = QgsAuxiliaryLayer::createProperty( p, vlayer );
    }

    indexes[p] = index;
  }

  details.settings = vlayer->labeling()->settings( providerId );

  return newAuxiliaryLayer;
}

bool QgsMapRendererJob::needTemporaryImage( QgsMapLayer* ml )
{
    if ( ml->type() == QgsMapLayer::VectorLayer )
    {
        QgsVectorLayer* vl = qobject_cast<QgsVectorLayer *>( ml );
        if ( vl->rendererV2() && vl->rendererV2()->forceRasterRender() )
        {
            //raster rendering is forced for this layer
            return true;
        }
        if ( mSettings.testFlag( QgsMapSettings::UseAdvancedEffects ) &&
                (( vl->blendMode() != QPainter::CompositionMode_SourceOver )
                 || ( vl->featureBlendMode() != QPainter::CompositionMode_SourceOver )
                 || ( vl->layerTransparency() != 0 ) ) )
        {
            //layer properties require rasterisation
            return true;
        }
    }

    return false;
}

void QgsServerProjectParser::addLayerProjectSettings( QDomElement& layerElem, QDomDocument& doc, QgsMapLayer* currentLayer ) const
{
  if ( !currentLayer )
  {
    return;
  }
  // Layer tree name
  QDomElement treeNameElem = doc.createElement( "TreeName" );
  QDomText treeNameText = doc.createTextNode( currentLayer->name() );
  treeNameElem.appendChild( treeNameText );
  layerElem.appendChild( treeNameElem );

  if ( currentLayer->type() == QgsMapLayer::VectorLayer )
  {
    QgsVectorLayer* vLayer = static_cast<QgsVectorLayer*>( currentLayer );
    const QSet<QString>& excludedAttributes = vLayer->excludeAttributesWms();

    int displayFieldIdx = -1;
    QString displayField = "maptip";
    QgsExpression exp( vLayer->displayExpression() );
    if ( exp.isField() )
    {
      displayField = static_cast<const QgsExpression::NodeColumnRef*>( exp.rootNode() )->name();
      displayFieldIdx = vLayer->fieldNameIndex( displayField );
    }

    //attributes
    QDomElement attributesElem = doc.createElement( "Attributes" );
    const QgsFields& layerFields = vLayer->pendingFields();
    for ( int idx = 0; idx < layerFields.count(); ++idx )
    {
      QgsField field = layerFields.at( idx );
      if ( excludedAttributes.contains( field.name() ) )
      {
        continue;
      }
      // field alias in case of displayField
      if ( idx == displayFieldIdx )
      {
        displayField = vLayer->attributeDisplayName( idx );
      }
      QDomElement attributeElem = doc.createElement( "Attribute" );
      attributeElem.setAttribute( "name", field.name() );
      attributeElem.setAttribute( "type", QVariant::typeToName( field.type() ) );
      attributeElem.setAttribute( "typeName", field.typeName() );
      QString alias = vLayer->attributeAlias( idx );
      if ( !alias.isEmpty() )
      {
        attributeElem.setAttribute( "alias", alias );
      }

      //edit type to text
      attributeElem.setAttribute( "editType", vLayer->editFormConfig()->widgetType( idx ) );
      attributeElem.setAttribute( "comment", field.comment() );
      attributeElem.setAttribute( "length", field.length() );
      attributeElem.setAttribute( "precision", field.precision() );
      attributesElem.appendChild( attributeElem );
    }
    //displayfield
    layerElem.setAttribute( "displayField", displayField );

    //geometry type
    layerElem.setAttribute( "geometryType", QgsWkbTypes::displayString( vLayer->wkbType() ) );

    layerElem.appendChild( attributesElem );
  }
}

void QgsQuickPrint::scalePointSymbols( int theScaleFactor, SymbolScalingType theDirection )
{
  if ( 0 >= theScaleFactor )
  {
    QgsDebugMsg( "invalid scale factor" );
    return;
  }
  QStringList myLayerSet = mpMapRenderer->layerSet();
  QStringListIterator myLayerIterator( myLayerSet );
  while ( myLayerIterator.hasNext() )
  {
    QString myLayerId = myLayerIterator.next();
    QgsDebugMsg( "Scaling point symbols for print for " + myLayerId );
    QgsMapLayer * mypLayer =
      QgsMapLayerRegistry::instance()->mapLayer( myLayerId );
    if ( mypLayer )
    {
      QgsVectorLayer *mypVectorLayer  =
        qobject_cast<QgsVectorLayer *>( mypLayer );
      if ( mypVectorLayer )
      {
        const QgsRenderer* mypRenderer = mypVectorLayer->renderer();
        const QList<QgsSymbol*> mySymbolList = mypRenderer->symbols();
        //
        // Single symbol
        //
        if ( 1 == mySymbolList.size() )
        {
          QgsSymbol * mypSymbol = mySymbolList.at( 0 );
          if ( mypSymbol->type() == QGis::Point )
          {
            if ( theDirection == ScaleUp )
            {
              mypSymbol->setPointSize( mypSymbol->pointSize() * theScaleFactor );
            }
            else //Scale Down
            {
              mypSymbol->setPointSize( mypSymbol->pointSize() / theScaleFactor );
            }
          }
        }
        else  //class breaks
        {
          QListIterator<QgsSymbol *> myIterator( mySymbolList );
          while ( myIterator.hasNext() )
          {
            QgsSymbol * mypSymbol = myIterator.next();
            if ( mypSymbol->type() == QGis::Point )
            {
              if ( theDirection == ScaleUp )
              {
                mypSymbol->setPointSize( mypSymbol->pointSize() * theScaleFactor );
              }
              else //Scale Down
              {
                mypSymbol->setPointSize( mypSymbol->pointSize() / theScaleFactor );
              }
            }
          } //symbol loop
        } //class breaks
      } //if vectorlayer
    } //if maplayer
  } //layer iterator
}

//.........这里部分代码省略.........
  // drawn into it will appear squashed), but a different origin.
  QRect myOriginalViewport = myPrintPainter.viewport(); //for restoring later
  myOriginX += myMapDimensionX + myHorizontalSpacing;
  myPrintPainter.setViewport( myOriginX,
                              myOriginY,
                              myOriginalViewport.width(),
                              myOriginalViewport.height() );
  //draw a rectangale around the legend frame
  //@TODO make this user settable
  if ( 0 == 1 ) //put some real logic here
  {
    myPrintPainter.drawRect( 0, 0, myLegendDimensionX, myLegendDimensionY );
  }
  //get font metric and other vars needed
  QFontMetrics myLegendFontMetrics( myLegendFont, &myPrinter );
  int myLegendFontHeight = myLegendFontMetrics.height();
  int myLegendXPos = 0;
  int myLegendYPos = 0;
  int myLegendSpacer = myLegendFontHeight / 2; //for vertical and horizontal spacing
  int myLegendVerticalSpacer = myLegendFontHeight / 3; //for vertical between rows
  int myIconWidth = myLegendFontHeight;
  myPrintPainter.setFont( myLegendFont );
  QStringList myLayerSet = mpMapRenderer->layerSet();
  QStringListIterator myLayerIterator( myLayerSet );
  //second clause below is to prevent legend spilling out the bottom
  while ( myLayerIterator.hasNext() &&
          myLegendYPos < myLegendDimensionY )
  {
    QString myLayerId = myLayerIterator.next();
    QgsMapLayer * mypLayer =
      QgsMapLayerRegistry::instance()->mapLayer( myLayerId );
    if ( mypLayer )
    {
      QgsVectorLayer *mypVectorLayer  =
        qobject_cast<QgsVectorLayer *>( mypLayer );
      // TODO: add support for symbology-ng renderers
      if ( mypVectorLayer && mypVectorLayer->renderer() )
      {
        QString myLayerName = mypVectorLayer->name();
        QIcon myIcon;
        QPixmap myPixmap( QSize( myIconWidth, myIconWidth ) );   //square
        //based on code from qgslegendlayer.cpp - see that file for more info
        const QgsRenderer* mypRenderer = mypVectorLayer->renderer();
        const QList<QgsSymbol*> mySymbolList = mypRenderer->symbols();
        //
        // Single symbol
        //
        double widthScale = ( myPrinter.logicalDpiX() + myPrinter.logicalDpiY() ) / 2.0 / 25.4;

        if ( 1 == mySymbolList.size() )
        {
          QgsSymbol * mypSymbol = mySymbolList.at( 0 );
          myPrintPainter.setPen( mypSymbol->pen() );
          myPrintPainter.setBrush( mypSymbol->brush() );
          myLegendXPos = 0 ;
          if ( mypSymbol->type() == QGis::Point )
          {
            QImage myImage;
            myImage = mypSymbol->getPointSymbolAsImage( widthScale );
            myPrintPainter.drawImage( myLegendXPos, myLegendYPos, myImage );
          }
          else if ( mypSymbol->type() == QGis::Line )
          {
            myPrintPainter.drawLine( myLegendXPos, myLegendYPos,
                                     myLegendXPos + myIconWidth,
                                     myLegendYPos + myIconWidth );

void QgsLineVectorLayerDirector::makeGraph( QgsGraphBuilderInterface *builder, const QVector< QgsPoint >& additionalPoints,
    QVector< QgsPoint >& tiedPoint ) const
{
  QgsVectorLayer *vl = mVectorLayer;

  if ( vl == NULL )
    return;

  int featureCount = ( int ) vl->featureCount() * 2;
  int step = 0;

  QgsCoordinateTransform ct;
  ct.setSourceCrs( vl->crs() );
  if ( builder->coordinateTransformationEnabled() )
  {
    ct.setDestCRS( builder->destinationCrs() );
  }
  else
  {
    ct.setDestCRS( vl->crs() );
  }

  tiedPoint = QVector< QgsPoint >( additionalPoints.size(), QgsPoint( 0.0, 0.0 ) );

  TiePointInfo tmpInfo;
  tmpInfo.mLength = std::numeric_limits<double>::infinity();

  QVector< TiePointInfo > pointLengthMap( additionalPoints.size(), tmpInfo );
  QVector< TiePointInfo >::iterator pointLengthIt;

  //Graph's points;
  QVector< QgsPoint > points;

  QgsFeatureIterator fit = vl->getFeatures( QgsFeatureRequest().setSubsetOfAttributes( QgsAttributeList() ) );

  // begin: tie points to the graph
  QgsAttributeList la;
  QgsFeature feature;
  while ( fit.nextFeature( feature ) )
  {
    QgsMultiPolyline mpl;
    if ( feature.constGeometry()->wkbType() == QGis::WKBMultiLineString )
      mpl = feature.constGeometry()->asMultiPolyline();
    else if ( feature.constGeometry()->wkbType() == QGis::WKBLineString )
      mpl.push_back( feature.constGeometry()->asPolyline() );

    QgsMultiPolyline::iterator mplIt;
    for ( mplIt = mpl.begin(); mplIt != mpl.end(); ++mplIt )
    {
      QgsPoint pt1, pt2;
      bool isFirstPoint = true;
      QgsPolyline::iterator pointIt;
      for ( pointIt = mplIt->begin(); pointIt != mplIt->end(); ++pointIt )
      {
        pt2 = ct.transform( *pointIt );
        points.push_back( pt2 );

        if ( !isFirstPoint )
        {
          int i = 0;
          for ( i = 0; i != additionalPoints.size(); ++i )
          {
            TiePointInfo info;
            if ( pt1 == pt2 )
            {
              info.mLength = additionalPoints[ i ].sqrDist( pt1 );
              info.mTiedPoint = pt1;
            }
            else
            {
              info.mLength = additionalPoints[ i ].sqrDistToSegment( pt1.x(), pt1.y(),
                             pt2.x(), pt2.y(), info.mTiedPoint );
            }

            if ( pointLengthMap[ i ].mLength > info.mLength )
            {
              Q_UNUSED( info.mTiedPoint );
              info.mFirstPoint = pt1;
              info.mLastPoint = pt2;

              pointLengthMap[ i ] = info;
              tiedPoint[ i ] = info.mTiedPoint;
            }
          }
        }
        pt1 = pt2;
        isFirstPoint = false;
      }
    }
    emit buildProgress( ++step, featureCount );
  }
  // end: tie points to graph

  // add tied point to graph
  int i = 0;
  for ( i = 0; i < tiedPoint.size(); ++i )
  {
    if ( tiedPoint[ i ] != QgsPoint( 0.0, 0.0 ) )
    {
      points.push_back( tiedPoint [ i ] );
//.........这里部分代码省略.........