I am working on a problem for creating a spectrum plot (it is a plot for drawing signal waves). I have decided to use QcustomPlot for this. the spectrum plot is not just for viewing waves, there are some tools I have to add to it. For example, one of the tools is a movable line in axisRect. I used QCPItemLine as a base class, but mouseMoveEvent() and mouseReleaseEvent() do not work for me. I used QcustomPlot event instead.

another problem is when you move mouse fast, the line item stops moving!.