Will Jessop spnkr

Using Obj-C with MacRuby/Rubymotion

This little post aims to help you to translate Objective-C Blocks into Ruby blocks. Let's start by taking a look at few examples of iOS API call where blocks are used for animations and enumeration

Ruby Lambda Syntaxes:

Im Rubymotion and MacRuby you can use all the Ruby Lambda syntaxes that are:

block = lambda { |param|  ... }

Here's A handy helper for showing loading cells in iOS Apps with Rubymotion

To use, simply include the class in your project and then from within your controller:

# in my controller

def tableView(tableView, cellForRowAtIndexPath: indexPath)
  # return a loading cell
 LoadingCell.loadingCellWithTableView(self.tableView)

	Each YouTube video has 4 generated images. They are predictably formatted as follows:

	http://img.youtube.com/vi/<insert-youtube-video-id-here>/0.jpg
	http://img.youtube.com/vi/<insert-youtube-video-id-here>/1.jpg
	http://img.youtube.com/vi/<insert-youtube-video-id-here>/2.jpg
	http://img.youtube.com/vi/<insert-youtube-video-id-here>/3.jpg

	The first one in the list is a full size image and others are thumbnail images. The default thumbnail image (ie. one of 1.jpg, 2.jpg, 3.jpg) is:

	http://img.youtube.com/vi/<insert-youtube-video-id-here>/default.jpg

	module Formotion
	module RowType
	class PickerWithSearchRow < PickerRow
	include RowType::ItemsMapper

	def after_build(cell)
	super
	@items_for_search = items
	keyboardDoneButtonView = UIToolbar.new
	keyboardDoneButtonView.barStyle = UIBarStyleBlack

	BW::Location.get(distance_filter: 10, desired_accuracy: :nearest_ten_meters) do \|result\|
	geocoder = CLGeocoder.alloc.init
	geocoder.reverseGeocodeLocation result[:to], completionHandler: lambda {\|location, x\|
	alert = UIAlertView.alloc.init

	alert.message = "#{location[0].locality} : #{location[0].postalCode}"
	alert.show
	}
	end

	- (void)controllerWillChangeContent:(NSFetchedResultsController *)controller
	{
	self.shouldReloadCollectionView = NO;
	self.blockOperation = [[NSBlockOperation alloc] init];
	}

	- (void)controller:(NSFetchedResultsController *)controller didChangeSection:(id<NSFetchedResultsSectionInfo>)sectionInfo
	atIndex:(NSUInteger)sectionIndex forChangeType:(NSFetchedResultsChangeType)type
	{
	__weak UICollectionView *collectionView = self.collectionView;

	module Base62
	BASE_CHARS = '0SKVnQFHhGs9qo7p8cRW54duMYNXTCErx2tDmwO3kabfUB1elLvjiIgyJAZ6Pz'.split('')
	BASE = BASE_CHARS.length
	BASE_ENCODED_MIN_LENGTH = 1

	def self.decode(number)
	# assure string
	number = number.to_s.reverse.split('')

	decoded = 0

	class MyController < UIViewController

	def viewDidLoad
	self.view.backgroundColor = UIColor.whiteColor
	alert.show
	end

	# ==============
	# = Properties =
	# ==============

	$:.unshift("/Library/RubyMotion/lib")

	require File.join(File.dirname(__FILE__), 'version')

	require 'motion/project'

	require 'bundler'

	Bundler.require

	class AppDelegate
	def application(application, didFinishLaunchingWithOptions:launchOptions)
	@window = UIWindow.alloc.initWithFrame(UIScreen.mainScreen.bounds)
	@window.rootViewController = ExampleViewController.alloc.init

	@window.makeKeyAndVisible
	true
	end
	end