[Desktop_printing] PageSize vs PageRegion?

[Alexander Larsson]

I'm working on the Gtk+ print dialog, and I have a question about
PageSize and PageRegion. I'm not sure when and how to use these. Reading
the PPD spec it seems like you're supposed to use PageSize if the user
wants a specific page size, and doesn't care from where it comes, and
PageRegion if the user specifies a specific InputSlot (and
RequiresPageRegion for that slot is true).

However, I'm representing InputSlot as a dropdown selection in the UI,
which means that InputSlot is always set (typically to its default
value). In most use cases I think the user just wants to pick a page
size though. In these cases we should ignore the InputSlot and use
PageSize. 

The obvious way to handle this would be to have an "automatic" choice
for InputSlot and use PageSize when that is set. I've been looking at
various existing ppds it looks like some have "Auto" or "AutoSelect"
choices. Is this something i can rely on?

So, if I have both a page size selector and an page source selector in
my print dialog, how do I know whether to use PageRegion or PageSize?

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 Alexander Larsson                                            Red Hat, Inc 
                   alexl at redhat.com    alla at lysator.liu.se 
He's a one-legged ninja waffle chef who must take medication to keep him sane. 
She's a manipulative French-Canadian vampire with the power to bend men's 
minds. They fight crime!