Your problem is here: -listcmd      => $self->LoadDS, What this does is assign the result of calling $self->LoadDS() to the key -listcmd. To create a callback, you need to pass -listcmd a sub reference, something like: -listcmd => sub { $self->LoadDS }

In reply to Re: OO Perl & Tk - problem with callbacks. by BUU
in thread OO Perl & Tk - problem with callbacks. by jdtoronto

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