Reposition control relative to the charting area

[vgromov]

I'm trying to find a way to reposition floating FMX control relative to the Chart's series area (i.e. virtual rect between axes). Is there any simple way to find its coordinates in terms of TChart control client area?
In addition, to track possible changes to that rectangle, I will need to (correct me if I'm wrong) handle chart's OnResize, OnAdd|Remove series events, providing there is no other sources of possible charting area change, like label font size, label formatting, tick lengths, etc.

[vgromov]

Sometimes I can't help, but feel retarded. The area in question may be requested as:
chart_->ChartRect,
and the right moment to get properly calculated rect is OnBeforeAxedDraw