AppController.rb

#  AppController.rb
#  test
require 'osx/cocoa'
OSX.ns_import :MyObject

class AppController < OSX::NSObject
  include OSX
  
  def initialize
    @tester = MyObject.alloc.init;
  end
  
  # Objective-Cのメソッドを呼び出し
  def doTest(sender)
    puts "doTest:"
    @tester.methodA_from(false, self)
  end
  ib_action :doTest
  
  # Objective-C側から呼び出してもらうコールバックメソッド
  objc_method :callback, [:BOOL, :BOOL]
  def callback(para)
    puts "callback:"
    puts "para is #{para}"
    puts "callback return <false>"
    return false
  end
end

MyObject.h

//  MyObject.h
//  test
#import <Cocoa/Cocoa.h>

@interface MyObject : NSObject {
}
- (void)methodA:(bool)param from:(id)caller;
@end

MyObject.m

//  MyObject.m
//  test
#import "MyObject.h"

@implementation MyObject : NSObject
- (void)methodA:(bool)param from:(id)caller
{
  NSLog(@"*** Call from RubyCocoa > param: %d", param);
  
  BOOL ret = [caller callback:false];
  NSLog(@"*** callback returned [%d]", ret);
  if (ret) {
    NSLog(@"*** callback returned <TRUE>");
  }
  else {
    NSLog(@"*** callback returned <FALSE>");
  }
  return;
}
@end