How to write an Objective-C Completion Block

Question

I\'m in a situation where need to call a class method from my view controller, have it do it\'s thing, but then perform some actions ONLY AFTER the class method has complete

Answer 1

Regarding to http://goshdarnblocksyntax.com/

As a local variable:

returnType (^blockName)(parameterTypes) = ^returnType(parameters) {...};

As a property:

@property (nonatomic, copy) returnType (^blockName)(parameterTypes);

As a method parameter:

- (void)someMethodThatTakesABlock:(returnType (^)(parameterTypes))blockName;

As an argument to a method call:

[someObject someMethodThatTakesABlock:^returnType (parameters) {...}];

As a typedef:

typedef returnType (^TypeName)(parameterTypes);
TypeName blockName = ^returnType(parameters) {...};