[MacRuby-devel] Crash with NSUInteger in delegate method

[Laurent Sansonetti]

Hi Łukasz,

On May 22, 2009, at 1:58 AM, Łukasz Adamczak wrote:

>> an NSNumber object should do it.
>
> Laurent, thanks for the answer. I believed that was the case.
>
> What about the delegate method case, though? I mean, the framework I'm
> playing with expects a certain delegate method and passes C unsigned
> ints to it:
>
> http://github.com/lukhnos/objectiveflickr/blob/b480aa39fa0e96f40a1b44523e0b6f918b2ed441/Source/ObjectiveFlickr.m#L525
>
> In this case I have no say in the Objective-C side of things. I write
> only Ruby code. The only thing I can do is to not implement the method
> at all (and lose some functionality provided by the framework).
> Obviously in an open-source environment I'm free to patch the library
> to my liking, but that's not optimal and not always possible.
>
> There may be more cases like this. Unless there is a policy on not
> using primitive types in delegates (is there?), more libraries (or
> maybe Cocoa itself?) can have problems with MacRuby.

MacRuby can deal with specialized delegate methods like this one, but  
you need to generate a bridgesupport file for the framework you're  
targeting. Most frameworks that ship with Mac OS X are already  
covered, but in your case you might want to manually cover  
ObjectiveFlickr too.

You can learn more by reading the gen_bridge_metadata(1) or  
BridgeSupport(5) man-pages.

What's going to happen is that informal protocols will be described  
and at runtime MacRuby will appropriately use the right method  
encoding in case the selector matches.

HTH,
Laurent