Hello, everyone.

So, I have a class called TwoDotsGraphicsScene which subclasses QGraphicsScene. In some place I add a QGraphicsGroup to it, where one of the items is QGraphicsLineItem:

Qt Code: 
  1. //some code....
  2.  
  3.     secondPoint = new QGraphicsItemGroup(0);
  4.     QLineF perpendicLine(QLineF(firstPoint->scenePos(), point).normalVector().unitVector());
  5.     perpendicLine.setLength(200);
  6.     QPointF centerPoint = perpendicLine.pointAt(0.5);
  7.     perpendicLine.translate(-centerPoint.x(), -centerPoint.y());
  8.  
  9.     perpLine = new QGraphicsLineItem(perpendicLine);
  10.     perpLine->setPen(QPen(Qt::red));
  11.     secondPointGroup->addToGroup(perpLine);
  12.  
  13.     this->addItem(secondPoint);
  14.  
  15.     //some code....
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perpLine - is a class public variable.

Next. This class has a slot correctLineAngle(int angle), in which I'd like to change a line's angle:

Qt Code: 
  1. void TwoDotsGraphicsScene::correctLineAngle(int angle)
  2. {
  3.     if(secondPoint == NULL)
  4.         return;
  5.  
  6.     qDebug() << "agnle " << angle;
  7.     perpLine->line().setAngle(angle);
  8.     qDebug() << "lineAngle " << perpLine->line().angle();
  9.  
  10.     calculateDistance();
  11. }
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But debug output is kind of like:
lineAngle 93.7022
agnle 121
lineAngle 93.7022
agnle 127
lineAngle 93.7022
agnle 133
lineAngle 93.7022
agnle 136
lineAngle 93.7022
So, I guess setAngle not having an effect. What should I do?