The user will add a new element (or a set of elements) to the set of elements displayed in the Listbox. This is done programmatically. The list can be recreated with no problem at any time. The problem is that this operation is done programmatically in Tcl (embedded in Perl) through Tcl.pm/Tcl::Tk inside a 

$int->Eval();#Tcl code which adds the element to the Listbox goes here

[download]

Unfortunately, me and my collegue were not able to find a way to call a Perl subrutine from inside the Eval code at the moment of adding the new element (I guess it is not possible at all). This is the reason why I am searching for an alternative to call this subrutine when the set of elements changes. It goeas without saying that for the meoment we can not substitute the Tcl code with Perl code, which would make this operation superfluous.

The original code posted in this thread is in Tk because I want(ed) to find a solution to my proposed approach - which is indipendent to Tcl.

In reply to Re^2: Tk programmatically monitor change in Listbox by IB2017
in thread Tk (Tcl::Tk) programmatically monitor change in Listbox by IB2017

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