Custom font in swift 4 make Fatal error: Unexpectedly found nil while unwrapping an Optional value

Question

I have to add custom font to my app. I added fonts to my project and listed infolist.

 enum Proxima: String {
        case regular = "Regular"
        func font(size: CGFloat) -> UIFont {
            return UIFont(name: "Proxima-\(rawValue)", size: size)!
        }
    }

Fatal error: Unexpectedly found nil while unwrapping an Optional value while calling

self.headTitle.font = UIFont.Proxima.regular.font(size: 30)

UPDATE

I added the target and also checked the copy bundle resources all are correct but still i got same error.

info.plist

Answer 1

Be sure that your files are added to your target

Also, don't forget to add them into the "Font provided by application" section of the Info.plist