Re: [Rubycocoa-talk] Calling Ruby from existing Cocoa App

[Jonathan P. <jp...@dc...>]

On 31 Jan 2006, at 6:46, Tim Burks wrote:

>> game_controller = OSX::NSDocumentController.sharedDocumentController
>> game = game_controller.documents.objectAtIndex(0)
>
> From there, I could directly call the methods of my object from Ruby:
>> game.start
>> game.sendEvent_forPlayer(10, 0)
>> game.stop

The same should work in the other direction too: assuming you can get  
a reference in objc to one of your ruby objects, you should be able  
to call methods on it. e.g.:

In ruby:

   game.setRubyObject(someobj)

Then in objc:

   [rubyObject someMethod: anArgument];

.. assuming you've got an instance variable called 'rubyObject' of  
type 'id' that has a setter method like:

-(void)setRubyObject:(id)obj
{
    [obj retain];
    [rubyObject autorelease];
    rubyObject = obj;
}


Another, possibly simpler, solution is to define an ObjC class in Ruby:

   class Foo < OSX::NSObject
      # ...
      def myMethod(arg1)
        puts arg1
      end
   end

Then, in objc:

   Class fooClass = NSClassFromString(@"Foo");
   id fooInstance = [[fooClass alloc] init];
   [fooInstance myMethod: @"hello"];
[the above code is untested - I think the idea is right though]



I imagine there'll be various compiler warnings since there are no  
prototypes for the messages being sent to the 'id' variable type. An  
objc interface declaration should fix that.



Cheers,

Jonathan