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C++ QgsVectorLayer::selectedFeaturesIterator方法代码示例

本文整理汇总了C++中QgsVectorLayer::selectedFeaturesIterator方法的典型用法代码示例。如果您正苦于以下问题:C++ QgsVectorLayer::selectedFeaturesIterator方法的具体用法?C++ QgsVectorLayer::selectedFeaturesIterator怎么用?C++ QgsVectorLayer::selectedFeaturesIterator使用的例子?那么, 这里精选的方法代码示例或许可以为您提供帮助。您也可以进一步了解该方法所在QgsVectorLayer的用法示例。


在下文中一共展示了QgsVectorLayer::selectedFeaturesIterator方法的2个代码示例,这些例子默认根据受欢迎程度排序。您可以为喜欢或者感觉有用的代码点赞,您的评价将有助于系统推荐出更棒的C++代码示例。

示例1: canvasPressEvent

void QgsMapToolMoveFeature::canvasPressEvent( QgsMapMouseEvent* e )
{
  delete mRubberBand;
  mRubberBand = nullptr;

  QgsVectorLayer* vlayer = currentVectorLayer();
  if ( !vlayer )
  {
    notifyNotVectorLayer();
    return;
  }

  if ( !vlayer->isEditable() )
  {
    notifyNotEditableLayer();
    return;
  }

  //find first geometry under mouse cursor and store iterator to it
  QgsPoint layerCoords = toLayerCoordinates( vlayer, e->pos() );
  QSettings settings;
  double searchRadius = QgsTolerance::vertexSearchRadius( mCanvas->currentLayer(), mCanvas->mapSettings() );
  QgsRectangle selectRect( layerCoords.x() - searchRadius, layerCoords.y() - searchRadius,
                           layerCoords.x() + searchRadius, layerCoords.y() + searchRadius );

  if ( vlayer->selectedFeatureCount() == 0 )
  {
    QgsFeatureIterator fit = vlayer->getFeatures( QgsFeatureRequest().setFilterRect( selectRect ).setSubsetOfAttributes( QgsAttributeList() ) );

    //find the closest feature
    QgsGeometry* pointGeometry = QgsGeometry::fromPoint( layerCoords );
    if ( !pointGeometry )
    {
      return;
    }

    double minDistance = std::numeric_limits<double>::max();

    QgsFeature cf;
    QgsFeature f;
    while ( fit.nextFeature( f ) )
    {
      if ( f.constGeometry() )
      {
        double currentDistance = pointGeometry->distance( *f.constGeometry() );
        if ( currentDistance < minDistance )
        {
          minDistance = currentDistance;
          cf = f;
        }
      }

    }

    delete pointGeometry;

    if ( minDistance == std::numeric_limits<double>::max() )
    {
      return;
    }

    mMovedFeatures.clear();
    mMovedFeatures << cf.id(); //todo: take the closest feature, not the first one...

    mRubberBand = createRubberBand( vlayer->geometryType() );
    mRubberBand->setToGeometry( cf.constGeometry(), vlayer );
  }
  else
  {
    mMovedFeatures = vlayer->selectedFeaturesIds();

    mRubberBand = createRubberBand( vlayer->geometryType() );
    QgsFeature feat;
    QgsFeatureIterator it = vlayer->selectedFeaturesIterator( QgsFeatureRequest().setSubsetOfAttributes( QgsAttributeList() ) );

    while ( it.nextFeature( feat ) )
    {
      mRubberBand->addGeometry( feat.constGeometry(), vlayer );
    }
  }

  mStartPointMapCoords = toMapCoordinates( e->pos() );
  mRubberBand->setColor( QColor( 255, 0, 0, 65 ) );
  mRubberBand->setWidth( 2 );
  mRubberBand->show();

}
开发者ID:Antoviscomi,项目名称:QGIS,代码行数:87,代码来源:qgsmaptoolmovefeature.cpp

示例2: canvasReleaseEvent


//.........这里部分代码省略.........
    {
      notifyNotEditableLayer();
      return;
    }

    QgsPoint layerCoords = toLayerCoordinates( vlayer, e->pos() );
    double searchRadius = QgsTolerance::vertexSearchRadius( mCanvas->currentLayer(), mCanvas->mapSettings() );
    QgsRectangle selectRect( layerCoords.x() - searchRadius, layerCoords.y() - searchRadius,
                             layerCoords.x() + searchRadius, layerCoords.y() + searchRadius );

    if ( vlayer->selectedFeatureCount() == 0 )
    {
      QgsFeatureIterator fit = vlayer->getFeatures( QgsFeatureRequest().setFilterRect( selectRect ).setSubsetOfAttributes( QgsAttributeList() ) );

      //find the closest feature
      QgsGeometry pointGeometry = QgsGeometry::fromPoint( layerCoords );
      if ( pointGeometry.isEmpty() )
      {
        return;
      }

      double minDistance = std::numeric_limits<double>::max();

      QgsFeature cf;
      QgsFeature f;
      while ( fit.nextFeature( f ) )
      {
        if ( f.hasGeometry() )
        {
          double currentDistance = pointGeometry.distance( f.geometry() );
          if ( currentDistance < minDistance )
          {
            minDistance = currentDistance;
            cf = f;
          }
        }
      }

      if ( minDistance == std::numeric_limits<double>::max() )
      {
        emit messageEmitted( tr( "Could not find a nearby feature in the current layer." ) );
        return;
      }

      QgsRectangle bound = cf.geometry().boundingBox();
      mStartPointMapCoords = toMapCoordinates( vlayer, bound.center() );

      if ( !mAnchorPoint )
      {
        mAnchorPoint = new QgsVertexMarker( mCanvas );
      }
      mAnchorPoint->setIconType( QgsVertexMarker::ICON_CROSS );
      mAnchorPoint->setCenter( mStartPointMapCoords );

      mStPoint = toCanvasCoordinates( mStartPointMapCoords );

      mRotatedFeatures.clear();
      mRotatedFeatures << cf.id(); //todo: take the closest feature, not the first one...

      mRubberBand = createRubberBand( vlayer->geometryType() );
      mRubberBand->setToGeometry( cf.geometry(), vlayer );
    }
    else
    {
      mRotatedFeatures = vlayer->selectedFeaturesIds();

      mRubberBand = createRubberBand( vlayer->geometryType() );

      QgsFeature feat;
      QgsFeatureIterator it = vlayer->selectedFeaturesIterator();
      while ( it.nextFeature( feat ) )
      {
        mRubberBand->addGeometry( feat.geometry(), vlayer );
      }
    }

    mRubberBand->setColor( QColor( 255, 0, 0, 65 ) );
    mRubberBand->setWidth( 2 );
    mRubberBand->show();

    double XDistance = mInitialPos.x() - mAnchorPoint->x();
    double YDistance = mInitialPos.y() - mAnchorPoint->y() ;
    mRotationOffset = atan2( YDistance, XDistance ) * ( 180 / PI );

    createRotationWidget();
    if ( e->modifiers() & Qt::ShiftModifier )
    {
      if ( mRotationWidget )
      {
        mRotationWidget->setMagnet( 45 );
      }
    }

    mRotationActive = true;

    return;
  }

  applyRotation( mRotation );
}
开发者ID:Zakui,项目名称:QGIS,代码行数:101,代码来源:qgsmaptoolrotatefeature.cpp


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