// // Copyright (c) 2018 Open Whisper Systems. All rights reserved. // // This view can be used to safely fill a region of a table // or collection view cell. These cells change the background // colors of their subviews when selected. This can inadvertently // change the color of filled subviews. This view will // reject a new background once its background has been set. @objc class NeverClearView: UIView { override var backgroundColor: UIColor? { didSet { if backgroundColor?.cgColor.alpha == 0 { backgroundColor = oldValue } } } }