Introduction to RubyMotion

The Cool Way to Build iOS Apps

By Gant Laborde

@GantLaborde

Avid Rubyist and generally immature guy

Co-Founder of IconoclastLabs.com

Author of Numerous RubyMotion projects and Pull Requests

Author of the book RubyMotion App Development
by Packt Publishing.

Motion Meetup Organizer

RubyMotion's Monthly Meetup

meetup.RubyMotion.com

Matt Garrison

@mattsgarrison

RubyMotion

RubyMotion - Wat?

/ˈro͞obē-mōSHən/

noun trademark
1. A proprietary toolchain, created by HipByte SPRL, for developing native iOS and OS X applications on Apple devices and computers by statically compiling the Ruby programming language.

Apps the Ruby Way

Quick Example

Objective-C button tap


  [button addTarget:self action:@selector(buttonTapped:) 
      forControlEvents: UIControlEventTouchUpInside];

  //  Elsewhere
  - (void)buttonTapped:(id)sender {
      self.view.backgroundColor = [UIColor redColor];
  }

RubyMotion button tap


  button.addTarget(self, action:'button_tapped', 
      forControlEvents:UIControlEventTouchUpInside)

  # Elsewhere
  def button_tapped
    self.view.backgroundColor = UIColor.redColor
  end

Better Example

Objective-C button tap


  [button addTarget:self action:@selector(buttonTapped:) 
      forControlEvents: UIControlEventTouchUpInside];

  //  Elsewhere

  - (void)buttonTapped:(id)sender {
      self.view.backgroundColor = [UIColor redColor];
  }

RubyMotion button tap (with sugarcube gem)


  button.on(:touch) do
    self.view.backgroundColor = :red.uicolor
  end

lessLike:objectiveC:

and more like_ruby

- Clay Allsopp

What's So Great About RubyMotion?

In my opinion

Gems and Community
Editor Independence
Testing!
Readability
Natively Compiled
The REPL

RubyMotion Analogy

RubyMotion is to Objective-C

As Coffeescript is to Javascript

... plus gems are kind of like jQuery plugins

... plus MacBacon has spec tests like Jasmine would

... plus the REPL lets you live-modify like developer tools

... plus it compiles and obfuscates your final codebase

... OK, this analogy got out of control

Let's Look At Code!

Classic - Hello World
Full App - Ruby Trivia
Games!

Hello World


  $ motion create test

Tests will fail


  class AppDelegate
    def application(application, didFinishLaunchingWithOptions:launchOptions)
      @window = UIWindow.alloc.initWithFrame(UIScreen.mainScreen.bounds)
      @window.rootViewController = HelloWorldController.new
      @window.makeKeyAndVisible
      true
    end
  end


  class HelloWorldController < UIViewController
    def viewDidLoad
      p "Hai"
    end
  end

Now tests pass!

Hello World - REPL


  main_view = UIApplication.sharedApplication.windows[0].rootViewController.view
  main_view.backgroundColor = UIColor.blueColor

OR, just command click the view!


  # REPL input
  self.backgroundColor = UIColor.whiteColor
  @label = UILabel.new
  @label.text = "Hello World"
  @label.sizeToFit
  self.addSubview(@label)
  
  # get down from there!
  @label.center = [100, 100]

OR, use sugarcube-repl's tree command.