如何混合 Objective-C 与 Ruby 编程 已翻译 100%

// CYAlert.h
#import <UIKit/UIKit.h>@interface  CYAlert : NSObject

+ (void)show;@end 
// CYAlert.m
#import "CYAlert.h"

@implementation CYAlert

+ (void)show {
    UIAlertView *alert = [[UIAlertView alloc] init];
    alert.title = @"This is Objective-C";
    alert.message = @"Mixing and matching!";
    [alert addButtonWithTitle:@"OK"];
    [alert show];
    [alert release];
}@end 

为了在RubyMotion应用中能正常使用，这里需要将CYAlert的两个文件都放置到类似 ./vendor/CYAlert 里面，然后在 Rakefile: 中告诉 RubyMotion 使用vendor_project创建那个文件夹。

Motion::Project::App.setup do |app|
  # Use `rake config' to see complete project settings.
  app.name = 'MixingExample'

  # ./vendor/CYAlert contains CYAlert.h and CYAlert.m
  app.vendor_project('vendor/CYAlert', :static)
end

class AppDelegate
  def application(application, didFinishLaunchingWithOptions:launchOptions)
    CYAlert.show
    true
  end
end

require 'motion-cocoapods'

Motion::Project::App.setup do |app|
  # ...
  app.pods do
    pod 'JSONKit'
  end
end

Ruby in Objective-C

# ./app/CYAlert.rb

class CYAlert
  def self.show
    alert = UIAlertView.alloc.init
    alert.title = "This is Ruby"
    alert.message = "Mixing and matching!"
    alert.addButtonWithTitle "OK"
    alert.show
  end
end

如果运行 rake static，将会把项目编译成静态库 ./build/<app name>-universal.a。下面我们通过几个步骤看看如何在Xcode项目中使用它：

// main.m

int main(int argc, char *argv[])
{
  @autoreleasepool {
      void RubyMotionInit(int, char **);
      RubyMotionInit(argc, argv);
      ...
  }
}

// CYAlert.h@interface  CYAlert : NSObject
+ (void)show;@end 

@implementation CYAlert
// Empty on purpose@end 

// ExampleDelegate.m

#import "CYAlert.h"

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    ...

    [CYAlert show];
    return YES;
}

所以，如果你觉得写Objective-C代码很痛苦的话（译者：觉得它比任何其他语言都痛苦），完全可以使用Ruby来写相同的功能，最后转换一下就OK。