addItem(_secondColHandle);
_secondColHandle->setXPos(_secondColHandlePos);
connect(_secondColHandle, SIGNAL(positionChanged(qreal)), this, SLOT(secondHandlePositionChanged(qreal)));
addItem(_secondColHandle);
_secondColHandle->setXPos(_secondColHandlePos);
connect(_secondColHandle, SIGNAL(positionChanged(qreal)), this, SLOT(secondHandlePositionChanged(qreal)));