Xcode: Using custom fonts inside Dynamic framework

I'm here a bit late, but I took PetahChristian's solution and created a Swift version in the form of an extension. This is working for me. I've found that when you try to get a font using a font name and a size using the regular way that it always looks in the main bundle for the font file, and there's no method that takes a bundle identifier as a parameter. It would be nice if Apple would make one.

Swift:

public extension UIFont {

    public static func jbs_registerFont(withFilenameString filenameString: String, bundle: Bundle) {

        guard let pathForResourceString = bundle.path(forResource: filenameString, ofType: nil) else {
            print("UIFont+:  Failed to register font - path for resource not found.")
            return
        }

        guard let fontData = NSData(contentsOfFile: pathForResourceString) else {
            print("UIFont+:  Failed to register font - font data could not be loaded.")
            return
        }

        guard let dataProvider = CGDataProvider(data: fontData) else {
            print("UIFont+:  Failed to register font - data provider could not be loaded.")
            return
        }

        guard let font = CGFont(dataProvider) else {
            print("UIFont+:  Failed to register font - font could not be loaded.")
            return
        }

        var errorRef: Unmanaged<CFError>? = nil
        if (CTFontManagerRegisterGraphicsFont(font, &errorRef) == false) {
            print("UIFont+:  Failed to register font - register graphics font failed - this font may have already been registered in the main bundle.")
        }
    }

}

Usage Example:

UIFont.jbs_registerFont(
    withFilenameString: "Boogaloo-Regular.ttf",
    bundle: Bundle(identifier: "com.JBS.JBSFramework")!
)