Re: [Rubycocoa-talk] Ruby/Cocoa and CoreData

[Sean L. <se...@da...>]

On 13 Sep 2005, at 14:43, Free (rupert.barrow) wrote:
> Has anyone got Ruby/RubyCocoa and CoreData working ?
> Are there any examples out there, of Apps (with GUI) and/or Tools  
> (without GUI).

This isn't quite the same, but bindings/KVO are used by CoreData, so  
this may be useful to you.

I've been working on enhancing RubyCocoa's handling of Key-Value  
observance to allow binding driven applications. I've written a  
little helper that allows code like this:

class Controller < OSX::NSObject

     attr_accessor  :status, :timeConnected
     cocoa_property :status, :timeConnected

     cocoa_depends  :status,          
[ :statusText, :isConnecting, :isConnected,
                                                          :isDisconnecti 
ng, :isDisconnected, :isWorking ]
     cocoa_depends  :timeConnected,  [ :timeConnectedText ]

end

(this was from a little proof-of-concept app I wrote to handle  
activating a PPP connection on my  server from by PB)

The cocoa_property class method creates wrappers for the setter  
methods for those properties that trigger KVO notifications. Note  
this is necessary even with the CVS HEAD RubyCocoa, even with the  
property support in there. That support will only trigger the  
notifications when the property is updated from the other side of the  
ObjC bridge. My code ensures that Ruby code that updates the property  
also triggers the notifications.

The cocoa_depends class method defines dependencies. This is  
necessary because the bridge seems to prevent the  
setKeys:triggerChangeNotificationsForDependentKey: class method on  
NSObject from operating correctly. (I haven't investigated why, but I  
can guess it's to do with the RubyCocoa wrapper for Ruby classes).

If you're interested I can post this, alternately is there any  
interest in getting these into the trunk? Is there perhaps a more  
elegant way of achieving this?

Sean

-- 
Sean Legassick
se...@da...