> I am learning cocoa slowly and right now I am trying to learn about
> building custom interfaces. One thing I cannot seem to find any
[quoted text clipped - 6 lines]
> files in Disco.app. Can anyone point me in the right direction to
> look? Thank you very much.
Certainly, but you're thinking about the problem in kind of the wrong way.
Nibs just give you objects. You can't load one nib "into" another one,
because the nib doesn't exist once it's loaded. A nib is just a file on
disk. After you load it, you no longer have a nib. Instead, you have a
window, some views, etc.
So you have one nib with a CustomView and another nib with another views.
After you've loaded them both, you have an NSView and then a bunch of
other NSViews. Can you add these other NSViews to your first NSView?
Absolutely. A perusal of the NSView documentation would be in order, but
you'll find methods like -addSubview: will get you where you want to go.

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Michael Ash
Rogue Amoeba Software