Important: Please read the Qt Code of Conduct -

For itemchange of QGraphicsLineItem

  • When you run the setLine function of QGraphicsLineItem, not called is itemchange function .

    If you change the shape of the line in setLine function , Will it not be a itemchange?

    Either way there is to know that the shape has been changed in the setLine?

  • There is no way to be notified about a shape change. An attempt to add that notification was made once, but it proved complicated, and GraphicsView is only maintained, not extended anymore.

    Best solution in your case is probably to write your own line item. Then you have full control.

  • Early answer Thank you .
    I try to implement their own line class .