#iOS#Swift Localized String For Xib File

XibLocalized.swift

public protocol Localizable {
    func localize()
}

public extension Localizable {
    
    public func localize(_ string: String?) -> String? {
        guard let term = string, term.hasPrefix("@") else {
            return string
        }
        guard !term.hasPrefix("@@") else {
            return term.substring(from: term.index(after: term.startIndex))
        }
        return NSLocalizedString(term.substring(from: term.index(after: term.startIndex)), comment: "")
    }
    
    public func localize(_ string: String?, _ setter: (String?) -> Void) {
        setter(localize(string))
    }

    public func localize(_ getter: (UIControlState) -> String?, _ setter: (String?, UIControlState) -> Void) {
        setter(localize(getter(.normal)), .normal)
        setter(localize(getter(.selected)), .selected)
        setter(localize(getter(.highlighted)), .highlighted)
        setter(localize(getter(.disabled)), .disabled)
    }
}

extension UIView: Localizable {
    public func localize() {
        subviews.forEach { $0.localize() }
    }
}

public extension UILabel {
    public override func localize() {
        super.localize()
        localize(text) { text = $0 }
    }
}

public extension UIButton {
    public override func localize() {
        super.localize()
        localize(title(for:), setTitle(_:for:))
    }
}

extension UIBarItem: Localizable {
    public func localize() {
        localize(title) { title = $0 }
    }
}

public extension UIBarButtonItem {
    public override func localize() {
        super.localize()
        customView?.localize()
    }
}

extension UINavigationItem: Localizable {
    public func localize() {
        localize(title) { title = $0 }
        localize(prompt) { prompt = $0 }
        titleView?.localize()
        leftBarButtonItems?.forEach { $0.localize() }
        rightBarButtonItems?.forEach { $0.localize() }
    }
}

extension UIViewController: Localizable {
    public func localize() {
        localize(title) { title = $0 }
        navigationItem.localize()
        tabBarItem?.localize()
        view.localize()
    }
}

// Create Localizable.strings files for support multi language
// In xib file, if you want to set localized text = "This is text" to the button, input in the button title text "@This is text", it will auto localized