[Brass]

I guess I just don't understand how NSTextView's are supposed to be configured for opacity with Interface Builder.

By default, they are 100% opaque. You can change the opacity of the background to whatever you want, so I've changed the opacity to 0% (ie, totally transparent, or so I thought). However, this just makes it entirely black (at run time, not in interface builder).

What am I doing wrong? How do I make my NSTextView transparent?

[Brass]

well I've tried passing the NSTextView the message:

setBackgroundColor:[NSColor clearColor]

and I've tried passing the same message to it's enclosingScrollView, and tried doing both, but I'm still just getting a black rectange for the NSTextView, even though the object(s) behind it are all white.

Any ideas anyone?

[Mac Boy]

Originally posted by Brass:
What am I doing wrong? How do I make my NSTextView transparent?

Most likely it is black because the NSTextView class tells the Quartz engine that it is opaque, and that nothing can show through it. You indicate this to Quartz by return YES from the function -(BOOL)isOpaque in the class. This is used to speed up drawing elements that are solid (as Quartz will not bother to draw anything below it).

The solution would be to create a subclass of NSTextView (say NSTransparentTextView) override the isOpaque method to return NO, and use this class in place of the regular TextView class.