iOS Design Patterns: The Builder

One of the things I’d like improve in 2016 is my knowledge of software engineering design patterns, with a particular emphasis on iOS. I’ll be posting a quick summary of each one I stumble across on the blog so that my future self can find things again easily.

Today’s pattern is called ‘The Builder’. The intent of the pattern is to make it easy to create objects with a lot of initial configurations, without bloating your code with a bunch of long initializers. The main difference between the builder and the factory design pattern is the complexity of the object being created (great answer here).

The Builder Pattern in Objective-C, by Klass Pieter provides an excellent example implementation. Creating an object with his builder implementation looks like this:

Pizza *pizza = [Pizza pizzaWithBlock:^(PizzaBuilder *builder]) { builder.size = 12; builder.pepperoni = YES; builder.mushrooms = YES; }];

I encourage you to read the whole post for further details and to keep this one in your back pocket the next time you type out multiple, magnificently long initializers.