diff --git a/src/gui/symbology-ng/qgsrendererv2widget.cpp b/src/gui/symbology-ng/qgsrendererv2widget.cpp
@@ -1,11 +1,142 @@
 #include "qgsrendererv2widget.h"
+#include "qgssymbolv2.h"
+#include "qgsvectorlayer.h"
+#include <QColorDialog>
+#include <QInputDialog>
+#include <QMenu>
 
 
 QgsRendererV2Widget::QgsRendererV2Widget( QgsVectorLayer* layer, QgsStyleV2* style )
     : QWidget(), mLayer( layer ), mStyle( style )
 {
 }
 
+void QgsRendererV2Widget::contextMenuViewCategories( const QPoint& p )
+{
+  QMenu contextMenu;
+  contextMenu.addAction( tr( "Change color" ), this, SLOT( changeSymbolColor( ) ) );
+  contextMenu.addAction( tr( "Change transparency" ), this, SLOT( changeSymbolTransparency() ) );
+  contextMenu.addAction( tr( "Change output unit" ), this, SLOT( changeSymbolUnit() ) );
+
+  if ( mLayer && mLayer->geometryType() == QGis::Line )
+  {
+    contextMenu.addAction( tr( "Change width" ), this, SLOT( changeSymbolWidth() ) );
+  }
+  else if ( mLayer && mLayer->geometryType() == QGis::Point )
+  {
+    contextMenu.addAction( tr( "Change size" ), this, SLOT( changeSymbolSize() ) );
+  }
+
+  contextMenu.exec( QCursor::pos() );
+}
+
+void QgsRendererV2Widget::changeSymbolColor()
+{
+  QList<QgsSymbolV2*> symbolList = selectedSymbols();
+  if ( symbolList.size() < 1 )
+  {
+    return;
+  }
+
+  QColor color = QColorDialog::getColor( symbolList.at( 0 )->color(), this );
+  if ( color.isValid() )
+  {
+    QList<QgsSymbolV2*>::iterator symbolIt = symbolList.begin();
+    for ( ; symbolIt != symbolList.end(); ++symbolIt )
+    {
+      ( *symbolIt )->setColor( color );
+    }
+    //populateCategories();
+  }
+}
+
+void QgsRendererV2Widget::changeSymbolTransparency()
+{
+  QList<QgsSymbolV2*> symbolList = selectedSymbols();
+  if ( symbolList.size() < 1 )
+  {
+    return;
+  }
+
+  bool ok;
+  double transparency = QInputDialog::getDouble( this, tr( "Transparency" ), tr( "Change symbol transparency" ), 1 - symbolList.at( 0 )->alpha(), 0.0, 1.0, 1, &ok );
+  if ( ok )
+  {
+    QList<QgsSymbolV2*>::iterator symbolIt = symbolList.begin();
+    for ( ; symbolIt != symbolList.end(); ++symbolIt )
+    {
+      ( *symbolIt )->setAlpha( 1 - transparency );
+    }
+    refreshSymbolView();
+  }
+}
+
+void QgsRendererV2Widget::changeSymbolUnit()
+{
+  QList<QgsSymbolV2*> symbolList = selectedSymbols();
+  if ( symbolList.size() < 1 )
+  {
+    return;
+  }
+
+  bool ok;
+  int currentUnit = ( symbolList.at( 0 )->outputUnit() == QgsSymbolV2::MM ) ? 0 : 1;
+  QString item = QInputDialog::getItem( this, tr( "Symbol unit" ), tr( "Select symbol unit" ), QStringList() << tr( "Millimeter" ) << tr( "Map unit" ), currentUnit, false, &ok );
+  if ( ok )
+  {
+    QgsSymbolV2::OutputUnit unit = ( item.compare( tr( "Millimeter" ) ) == 0 ) ? QgsSymbolV2::MM : QgsSymbolV2::MapUnit;
+
+    QList<QgsSymbolV2*>::iterator symbolIt = symbolList.begin();
+    for ( ; symbolIt != symbolList.end(); ++symbolIt )
+    {
+      ( *symbolIt )->setOutputUnit( unit );
+    }
+    refreshSymbolView();
+  }
+}
+
+void QgsRendererV2Widget::changeSymbolWidth()
+{
+  QList<QgsSymbolV2*> symbolList = selectedSymbols();
+  if ( symbolList.size() < 1 )
+  {
+    return;
+  }
+
+  bool ok;
+  double width = QInputDialog::getDouble( this, tr( "Width" ), tr( "Change symbol width" ), dynamic_cast<QgsLineSymbolV2*>( symbolList.at( 0 ) )->width(), 0.0, 999999, 1, &ok );
+  if ( ok )
+  {
+    QList<QgsSymbolV2*>::iterator symbolIt = symbolList.begin();
+    for ( ; symbolIt != symbolList.end(); ++symbolIt )
+    {
+      dynamic_cast<QgsLineSymbolV2*>( *symbolIt )->setWidth( width );
+    }
+    refreshSymbolView();
+  }
+}
+
+void QgsRendererV2Widget::changeSymbolSize()
+{
+  QList<QgsSymbolV2*> symbolList = selectedSymbols();
+  if ( symbolList.size() < 1 )
+  {
+    return;
+  }
+
+  bool ok;
+  double size = QInputDialog::getDouble( this, tr( "Size" ), tr( "Change symbol size" ), dynamic_cast<QgsMarkerSymbolV2*>( symbolList.at( 0 ) )->size(), 0.0, 999999, 1, &ok );
+  if ( ok )
+  {
+    QList<QgsSymbolV2*>::iterator symbolIt = symbolList.begin();
+    for ( ; symbolIt != symbolList.end(); ++symbolIt )
+    {
+      dynamic_cast<QgsMarkerSymbolV2*>( *symbolIt )->setSize( size );
+    }
+    refreshSymbolView();
+  }
+}
+
 
 
 ////////////

diff --git a/src/gui/symbology-ng/qgsrendererv2widget.h b/src/gui/symbology-ng/qgsrendererv2widget.h
@@ -22,6 +22,7 @@ class QgsSymbolV2SelectorDialog;
 */
 class GUI_EXPORT QgsRendererV2Widget : public QWidget
 {
+    Q_OBJECT
   public:
     QgsRendererV2Widget( QgsVectorLayer* layer, QgsStyleV2* style );
 
@@ -33,6 +34,24 @@ class GUI_EXPORT QgsRendererV2Widget : public QWidget
   protected:
     QgsVectorLayer* mLayer;
     QgsStyleV2* mStyle;
+
+    /**Subclasses may provide the capability of changing multiple symbols at once by implementing the following two methods
+      and by connecting the slot contextMenuViewCategories(const QPoint&)*/
+    virtual QList<QgsSymbolV2*> selectedSymbols() { return QList<QgsSymbolV2*>(); }
+    virtual void refreshSymbolView() {}
+
+  protected slots:
+    void contextMenuViewCategories( const QPoint& p );
+    /**Change color of selected symbols*/
+    void changeSymbolColor();
+    /**Change opacity of selected symbols*/
+    void changeSymbolTransparency();
+    /**Change units mm/map units of selected symbols*/
+    void changeSymbolUnit();
+    /**Change line widths of selected symbols*/
+    void changeSymbolWidth();
+    /**Change marker sizes of selected symbols*/
+    void changeSymbolSize();
 };
 
 

diff --git a/src/ui/qgsgraduatedsymbolrendererv2widget.ui b/src/ui/qgsgraduatedsymbolrendererv2widget.ui
@@ -153,6 +153,9 @@
    </item>
    <item>
     <widget class="QTreeView" name="viewGraduated">
+     <property name="contextMenuPolicy">
+      <enum>Qt::CustomContextMenu</enum>
+     </property>
      <property name="rootIsDecorated">
       <bool>false</bool>
      </property>