Well, first of all... when you do

data => \&gotodata,
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you're doing essentially the same thing as:

data => sub { gotodata(@_) },
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(they aren't the same thing, exactly, but they're functionally equivalent for your purposes, one is a named referrence and the other is an anonomous referrence to essentially the same thing). I bother to point that out because then it's easier to see the transition to what you should be doing for method calls, which is this:

data => sub { $self->gotodata(@_) },
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That is: creating an anonomous subroutine reference for a closure around the method call.