Swift之本地国际化与App内切换语言

添加语言库

• 点击项目 -> PROJECT -> Info -> Localizations -> + , 添加需要的语言;

• 添加好的语言库如下所示:

• 创建Localizable.strings

• 然后选择新创建的 Localizable.string, 选中所需要的语言;

Localizable.strings 文件写入

• 添加语言库成功之后, Localizable.strings就生成了English、Chinese Simplified、Chinese Traditional三个语言文件;
• Localizable.strings 文件中写入, 以"key" = “value”; 这样的格式;
• English:

INTERNATIONALIZATION = "Internationalization";
CHANGE = "switch";
HANDSOME = "Handsome Boy";

• Chinese Simplified

INTERNATIONALIZATION = "国际化";
CHANGE = "切换";
HANDSOME = "帅哥";

• Chinese Traditional

INTERNATIONALIZATION = "國際化";
CHANGE = "切換";
HANDSOME = "帥哥";

YDWLocalizationHelper

import UIKit

class YDWLocalizationHelper: NSObject {

    fileprivate static let kSharedSettingsKey = "DefaultUserSettings"
    
    var language: Language
    
    enum Language: String {
        case Chinese = "zh-Hans"
        case English = "en"
        case Tradition = "zh-Hant"
        case Vietnamese = "vi"
        
        var code: String {
            return rawValue
        }
    }

    // MARK: 创建单例
    static let shared: YDWLocalizationHelper = {
        let appSettings: YDWLocalizationHelper
        if let savedData = UserDefaults.standard.object(forKey: YDWLocalizationHelper.kSharedSettingsKey) as? Data,
            let defaultSettings = NSKeyedUnarchiver.unarchiveObject(with: savedData) as? YDWLocalizationHelper {
            appSettings = defaultSettings
        } else {
            appSettings = YDWLocalizationHelper()
        }
        return appSettings
    }()
    
    // MARK: 获取键值
    func valueWithKey(key: String!) -> String {
        let str = NSLocalizedString(key, comment: "")
        return str
    }

    // MARK: - 保存用户当前语言
    static func saveSharedInstance() {
        let data = NSKeyedArchiver.archivedData(withRootObject: YDWLocalizationHelper.shared)
        UserDefaults.standard.set(data, forKey: YDWLocalizationHelper.kSharedSettingsKey)
    }

    static func localeIsChinese() -> Language {
        if let lang = Locale.preferredLanguages.first {
            if lang.hasPrefix("zh") {
                if lang.contains("Hant") || lang.contains("Trad") {
                    return .Tradition
                }
                return .Chinese
            } else if lang.contains("en") {
                return .English
            } else if lang.hasPrefix("viet") {
                return .Vietnamese
            } else {
                return .English
            }
        } else {
            return .English
        }
    }

    // MARK: 首次进入语言
    override init() {
        language = YDWLocalizationHelper.localeIsChinese()
        super.init()
    }

}

private var bundleByLanguageCode: [String: Foundation.Bundle] = [:]

extension YDWLocalizationHelper.Language {
    var bundle: Foundation.Bundle? {
        if let bundle = bundleByLanguageCode[code] {
            return bundle
        } else {
            let mainBundle = Foundation.Bundle.main
            if let path = mainBundle.path(forResource: code, ofType: "lproj"),
                let bundle = Foundation.Bundle(path: path) {
                bundleByLanguageCode[code] = bundle
                return bundle
            } else {
                return nil
            }
        }
    }
}

class Bundle: Foundation.Bundle {
    override func localizedString(forKey key: String, value: String?, table tableName: String?) -> String {
        if let bundle = YDWLocalizationHelper.shared.language.bundle {
            return bundle.localizedString(forKey: key, value: value, table: tableName)
        } else {
            return super.localizedString(forKey: key, value: value, table: tableName)
        }
    }
}

语言切换

• AppDelegate中:

	func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
        object_setClass(Foundation.Bundle.main, Bundle.self)
        return true
	}

• 使用:设定时只需要在控件上, 通过YDWLocalizationHelper.shared.valueWithKey(key: “INTERNATIONALIZATION”)来设定即可; 而切换语言只需要桶设定YDWLocalizationHelper.shared.language = .Chinese即可;(其中valueWithKey和YDWLocalizationHelper.shared.language实现如下)

// comment 是传参, 假如value中需要外界来决定内容,可以用%@,然后comment传参
NSLocalizedString("key", comment: "")

// 切换语言时,只要设置就可以:
AppSettings.shared.language = .English //  .Chinese 

• 最后重载RootViewController即可:

	let appDelegate = UIApplication.shared.delegate as! AppDelegate
    appDelegate.setupRootViewController()

• 对于story 中的国际化, 需要重设一下RootViewController

    func resetRootViewController() {
        if let appdelegate = UIApplication.shared.delegate {
            let storyBoard = UIStoryboard.init(name: "Main", bundle: nil)
            if let mainController = storyBoard.instantiateViewController(withIdentifier: "rootViewController") as? UINavigationController {
                appdelegate.window??.rootViewController = mainController
            }
        }
    }

效果展示

完整示例

Swift之Internationalization本地国际化和App内切换语言