Swift: Get all subviews of a specific type and add to an array

Question

I have a custom class of buttons in a UIView that I\'d like to add to an array so that they\'re easily accessible. Is there a way to get all subviews of a specific class and

Answer 1

For this case, I think we could use Swift's first.where syntax, which is more efficient than filter.count, filter.isEmpty.

Because when we use filter, it will create a underlying array, thus not effective, imagine we have a large collection.

So just check if a view's subViews collection contains a specific kind of class, we can use this

let containsBannerViewKind = view.subviews.first(where: { $0 is BannerView }) != nil

which equivalent to: find me the first match to BannerView class in this view's subViews collection. So if this is true, we can carry out our further logic.

Reference: https://github.com/realm/SwiftLint/blob/master/Rules.md#first-where