Video Tutorial: Objective-C Blocks

Challenge

Your challenge is to download the challenge starter project and follow the instructions in AppDelegate.m. Basically, use block syntax to order some soup using order:withCompletionHandler: on the Ray class. Also be sure to read and understand all the code in the project.

Download demo code

Download challenge solution

Helpful links

• Why must blocks be copied and not retained?
• WWDC 2011 video: Blocks and Grand Central Dispatch in Practice
• How to Use Blocks in iOS 5 Tutorial, Part 2

Errata

• The diagram on the “Declaring a Block” slide has the angle bracket (^) for the variable name outside the parenthesis, but it should be inside the parenthesis like in the code example below the diagram.