29  view()->horizontalScrollBar()->setValue( 
view()->horizontalScrollBar()->value() - ( event->x() - mLastMousePos.x() ) );
 
   30  view()->verticalScrollBar()->setValue( 
view()->verticalScrollBar()->value() - ( event->y() - mLastMousePos.y() ) );
 
   31  mLastMousePos = 
event->pos();
 
 
   36  if ( event->button() == Qt::MiddleButton )
 
   38    view()->setTool( mPreviousViewTool );
 
 
   44  mLastMousePos = 
view()->mapFromGlobal( QCursor::pos() );
 
   45  mPreviousViewTool = 
view()->tool();
 
 
A QgsModelViewMouseEvent is the result of a user interaction with the mouse on a QgsModelGraphicsView...