Menu bar in TCanvas

OK, I have a very basic question:

I would like to inspect a set of histograms written in a root file.
I would like to look at the one or a few histograms in a canvas
and be able to, for example, use the cursor to read coordinates
in 2D histos.

My problem: the canvas menu bar shows up only at the
end of my stepping thru the histograms. How do I turn
on the menu bar starting from the first c1->Update();

Thanks in advance (short root *.C cosde attached)


P.S. Does anybody has good example of a ROOT macro
used to inspect a set of histograms?
run60789.root (679 KB)
autcheck.C (2.79 KB)

You should not use statements like “gets” that block the event loop.
I have simplified your script, removing several lines and adding two.
see attachment.

autcheck.C (2.75 KB)