Programmatically Scale selected UIView components on Zoom

Question

Hi,

I have a UIScrollView that nests a UIImage and several symbols that are placed on the image programatically.

When the user zooms I need to scale these symbols up to have them keep the same size, whilst the underlying image is zoomed.

I placed the symbols and the image in a UIView to ensure the symbol position is alidned to image coordinates.

First attempt:

My attempt to do this is to place a routine in the viewForZoomingInScrollview method. But when reading the myScrollView.zoomScale parameter I hit the recursion problem that causes an infinte loop on viewForZoomingInScrollview (see stackoverflow bug report).

I now struggle to find a way to determine the current zoomScale, hence am unable to determine the scale-factor that I need to apply when scaling my symbols.

Any hints how I can do this?