Zooming function on a QWidget

Question

I have a QWidget where I am drawing some lines and I would like to enable/implement a zooming function so as to better see the picture which I am drawing. And I want to conn

Answer 1

I used this solution before and I have to say that is obsoleted in the las Qt versions. To create this function is all the same except " event->delta()", now it is written "event->angleDelta().y()"