快速改变语言

Question

现在我知道苹果不推荐这个。

  

通常，您不应在应用程序中更改iOS系统语言（通过使用AppleLanguages pref键）。这违反了在Settings应用程序中切换语言的基本iOS用户模型，并且还使用了未记录的首选项密钥，这意味着在将来的某个时刻，密钥名称可能会更改，这会破坏您的应用程序。

然而，这是一个应用程序，即时更改语言是有道理的，只要相信我。我也知道这个问题在这里被问到：Changing language on the fly, in running iOS, programmatically。然而，这已经老了，我想知道是否有更新，更好或更简单的方法来做到这一点。目前在我的应用程序中，我有一个语言选择屏幕。单击此视图中的按钮将使用与该按钮关联的语言调用以下函数：

 func changeLang(language: String) {

    if language != (currentLang as! String?)! {
        func handleCancel(alertView: UIAlertAction!)
        {

        }
        var alert = UIAlertController(title: NSLocalizedString("language", comment: "Language"), message: NSLocalizedString("languageWarning", comment: "Warn User of Language Change Different Than Defaults"), preferredStyle: UIAlertControllerStyle.Alert)

        alert.addAction(UIAlertAction(title: "Cancel", style: UIAlertActionStyle.Cancel, handler:handleCancel))
        alert.addAction(UIAlertAction(title: "Yes", style: UIAlertActionStyle.Default, handler:{ (UIAlertAction) in

            NSUserDefaults.standardUserDefaults().setObject([language], forKey: "AppleLanguages")
            NSUserDefaults.standardUserDefaults().synchronize()
            println(self.currentLang)

            let alert = UIAlertView()
            alert.title = NSLocalizedString("language", comment: "Sign In Failed")
            alert.message = NSLocalizedString("languageChangeNotification", comment: "Notify of language change")
            alert.addButtonWithTitle(NSLocalizedString("ok", comment: "Okay"))
            alert.show()

            self.performSegueWithIdentifier("welcome", sender: AnyObject?())


        }))
        self.presentViewController(alert, animated: true, completion: {
        })
    } else {
        self.performSegueWithIdentifier("welcome", sender: AnyObject?())
    }

}

示例：

@IBAction func english(sender: UIButton) {
        changeLang("en")

    }

如果用户选择的语言与他们自己的语言不同，则会收到确认提示，然后请求重新启动设备。这就是我想要改变的。在应用程序重新启动之前，NSUSerDefaults的这一部分似乎不会同步。证据：

let currentLang: AnyObject? = NSLocale.preferredLanguages()[0]
println(currentLang)
// Prints english
changeLang("zh-Hans")
println(currentLang)
// Prints english still until restart 

Apple目前的国际化系统很棒，我打算使用它。但是，如何通过强制更新NSUSerDefaults来动态更改语言？

修改：我建议现在使用此library执行此操作。祝你好运！

Answer 1

基本上你必须教你如何通过加载不同的捆绑文件来捆绑语言。

我将Objective-C code翻译成斯威夫特 - 并保持NSBundle类别不变。

结果是一个视图控制器类，它提供了一个languageDidChange()方法来覆盖。

一个NSBundle + Language.h

#import <Foundation/Foundation.h>

@interface NSBundle (Language)
+(void)setLanguage:(NSString*)language;

@end

一个NSBundle + Language.m

#import "NSBundle+Language.h"
#import <objc/runtime.h>

static const char associatedLanguageBundle=0;

@interface PrivateBundle : NSBundle
@end

@implementation PrivateBundle
-(NSString*)localizedStringForKey:(NSString *)key
                            value:(NSString *)value
                            table:(NSString *)tableName
{
    NSBundle* bundle=objc_getAssociatedObject(self, &associatedLanguageBundle);
    return bundle ? [bundle localizedStringForKey:key
                                            value:value
                                            table:tableName] : [super localizedStringForKey:key
                                                                                      value:value
                                                                                      table:tableName];
}
@end

@implementation NSBundle (Language)
+(void)setLanguage:(NSString*)language
{
    static dispatch_once_t onceToken;
    dispatch_once(&onceToken, ^{
        object_setClass([NSBundle mainBundle],[PrivateBundle class]);
    });

    objc_setAssociatedObject([NSBundle mainBundle], &associatedLanguageBundle, language ?
                             [NSBundle bundleWithPath:[[NSBundle mainBundle] pathForResource:language ofType:@"lproj"]] : nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}
@end

AppDelegate.swift

import UIKit

@UIApplicationMain
class AppDelegate: UIResponder, UIApplicationDelegate {

    var window: UIWindow?


    func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {

        NSNotificationCenter.defaultCenter().addObserver(self, selector: "languageWillChange:", name: "LANGUAGE_WILL_CHANGE", object: nil)

        let targetLang = NSUserDefaults.standardUserDefaults().objectForKey("selectedLanguage") as? String

        NSBundle.setLanguage((targetLang != nil) ? targetLang : "en")
        return true
    }

    func languageWillChange(notification:NSNotification){
        let targetLang = notification.object as! String
        NSUserDefaults.standardUserDefaults().setObject(targetLang, forKey: "selectedLanguage")
        NSBundle.setLanguage(targetLang)
        NSNotificationCenter.defaultCenter().postNotificationName("LANGUAGE_DID_CHANGE", object: targetLang)
    }    
}

BaseViewController.swift

import UIKit



class BaseViewController: UIViewController {

    @IBOutlet weak var englishButton: UIButton!
    @IBOutlet weak var spanishButton: UIButton!

    deinit{
        NSNotificationCenter.defaultCenter().removeObserver(self)
    }
    override func viewDidLoad() {
        super.viewDidLoad()
        NSNotificationCenter.defaultCenter().addObserver(self, selector: "languageDidChangeNotification:", name: "LANGUAGE_DID_CHANGE", object: nil)
        languageDidChange()

    }

    override func didReceiveMemoryWarning() {
        super.didReceiveMemoryWarning()
        // Dispose of any resources that can be recreated.
    }

    @IBAction func switchLanguage(sender: UIButton) {

        var localeString:String?
        switch sender {
        case englishButton: localeString = "en"
        case spanishButton: localeString = "es"
        default: localeString = nil
        }


        if localeString != nil {
            NSNotificationCenter.defaultCenter().postNotificationName("LANGUAGE_WILL_CHANGE", object: localeString)
        }
    }


    func languageDidChangeNotification(notification:NSNotification){
        languageDidChange()
    }

    func languageDidChange(){

    }


}

ViewController.swift

import UIKit

class ViewController: BaseViewController {

    @IBOutlet weak var helloLabel: UILabel!
    override func viewDidLoad() {
        super.viewDidLoad()
    }

    override func languageDidChange() {
        super.languageDidChange()
        self.helloLabel.text = NSLocalizedString("Hello", comment: "")

    }
}

而不是使用BaseViewController的子类，您的viewcontrollers也可以发布“LANGUAGE_WILL_CHANGE”并监听“LANGUAGE_DID_CHANGE”

我在这里推送完整的项目：ImmediateLanguageSwitchSwift

Answer 2

对我来说，“Swift Localize”库解决了即时语言切换。

Answer 3

如上面“ vikingosegundo ”所回答，在Objective c中具有类别 这是Swift extension版本

import ObjectiveC

private var associatedLanguageBundle:Character = "0"

class PrivateBundle: Bundle {
    override func localizedString(forKey key: String, value: String?, table tableName: String?) -> String {
        let bundle: Bundle? = objc_getAssociatedObject(self, &associatedLanguageBundle) as? Bundle
        return (bundle != nil) ? (bundle!.localizedString(forKey: key, value: value, table: tableName)) : (super.localizedString(forKey: key, value: value, table: tableName))

    }
}

extension Bundle {
    class func setLanguage(_ language: String) {
        var onceToken: Int = 0

        if (onceToken == 0) {
            /* TODO: move below code to a static variable initializer (dispatch_once is deprecated) */
            object_setClass(Bundle.main, PrivateBundle.self)
        }
        onceToken = 1
        objc_setAssociatedObject(Bundle.main, &associatedLanguageBundle, (language != nil) ? Bundle(path: Bundle.main.path(forResource: language, ofType: "lproj") ?? "") : nil, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
    }
}

剩余代码将与“ vikingosegundo”中提到的相同

始终欢迎更正：）

Answer 4

使用此行代码，它将更改布局而无需关闭应用程序。 从右到左

<?php
public function store(Request $request)
{
    $this->validate($request, array(
    'date_input' => 'required|date',
    'number_of_mortality' => 'required|numeric',
    ) );

    $cycle = Cycle::select('id', 'date_start_raise')
        ->where('date_start_raise','<=',$request->get('date_input'))
        ->where('date_end_raise','>=',$request->get('date_input'))
        ->orderBy('date_end_raise desc') //not sure, I've never used laravel
        ->limit(1) //not sure, I've never used laravel
        ->get();

    $id = 0;
    $chickenAge = 0;
    foreach($cycle as $value){
        $id = $value->id;
    }
    if ($id) {
        $start = new Carbon($value->date_start_raise);
        $chickenAge = $start->diffInDays(request('date_input')) ;
    }

    return Mortality::create([
        'date_input' => request('date_input'),
        'number_of_mortality' => request('number_of_mortality'),
        'chicken_age' => $chickenAge,
        'cause_of_death' => request('cause_of_death'),
        'cycle_id'  => $id,
        'user_id'  => Auth::id()
    ]);
}

从左向右翻转

console.clear();

const array = [
  {id: 1, parent: 0},
  {id: 2, parent: 1},
  {id: 3, parent: 1},
  {id: 4, parent: 1}
];

const newArray = array.filter(el => el.id === 2 && {...el});
const newArray2 = array.map(el => ({...el}));
newArray[0].children = 3; // mutation of initial array
const newEl = {...array[2]};

console.log('Array: ', array);
console.log('newArray2: ', newArray2);
console.log('array[1] === newArray[0]: ', array[1] === newArray[0]); // WTF???
console.log('array[1] === newArray2[1]: ', array[1] === newArray2[1]);
console.log('newEl === array[2]: ', newEl === array[2]);

，如果您想更改文本字段布局或更改文本，请使用此代码，因为我遇到了这个问题。 textfield的文本未更改布局。检查此代码以更改文本字段文本的布局。

UIView.appearance().semanticContentAttribute = .forceRightToLeft