What is an IBOutletCollection in iOS??

When we try to create a new IBOutlet or new IBAction, a third option shows up named IBOutletCollection. I always wondered what it is, but never got a chance to check that out. If you already know what it is, then please skip this article.

As the name says, an IBOutletCollection is a collection of IBOutlets. It can either be a collection of UI elements.

An IBOutletCollection of UIButton in code will look like this :

@IBOutlet var starButtons: [UIButton]!

It will be an array of UIButton objects.

There are two rather curious things to note about an IBOutletCollection array:

• Its order is not necessarily guaranteed. The order of an outlet collection appears to be roughly the order in which their connections are established in Interface Builder. However, there are numerous reports of that order changing across versions of Xcode, or as a natural consequence of version control. Nonetheless, having code rely on a fixed order is strongly discouraged.
• No matter what type is declared for the property, an IBOutletCollection is always an NSArray