iOS開發(fā)教程之APP內(nèi)部切換語言的實(shí)現(xiàn)方法

+ (void)load {
 static dispatch_once_t onceToken;
 dispatch_once(&onceToken, ^{
  //動態(tài)繼承、交換，方法類似KVO，通過修改[NSBundle mainBundle]對象的isa指針，使其指向它的子類CLBundle，這樣便可以調(diào)用子類的方法；其實(shí)這里也可以使用method_swizzling來交換mainBundle的實(shí)現(xiàn)，來動態(tài)判斷，可以同樣實(shí)現(xiàn)。
  object_setClass([NSBundle mainBundle], [CLBundle class]);
 });
}

- (NSString *)localizedStringForKey:(NSString *)key value:(NSString *)value table:(NSString *)tableName {
 if ([CLBundle cl_mainBundle]) {
  return [[CLBundle cl_mainBundle] localizedStringForKey:key value:value table:tableName];
 } else {
  return [super localizedStringForKey:key value:value table:tableName];
 }
}

+ (NSBundle *)cl_mainBundle {
 if ([NSBundle currentLanguage].length) {
  NSString *path = [[NSBundle mainBundle] pathForResource:[NSBundle currentLanguage] ofType:@"lproj"];
  if (path.length) {
   return [NSBundle bundleWithPath:path];
  }
 }
 return nil;
}

+ (NSString *)currentLanguage {
 return [CLLanguageManager userLanguage] ? : [NSLocale preferredLanguages].firstObject;
}

+ (void)setUserLanguage:(NSString *)userLanguage {
 //跟隨手機(jī)系統(tǒng)
 if (!userLanguage.length) {
  [self resetSystemLanguage];
  return;
 }
 //用戶自定義
 [[NSUserDefaults standardUserDefaults] setValue:userLanguage forKey:CLUserLanguageKey];
 [[NSUserDefaults standardUserDefaults] setValue:@[userLanguage] forKey:@"AppleLanguages"];
 [[NSUserDefaults standardUserDefaults] synchronize];
}

+ (NSString *)userLanguage {
 return [[NSUserDefaults standardUserDefaults] valueForKey:CLUserLanguageKey];
}

/**
 重置系統(tǒng)語言
 */
+ (void)resetSystemLanguage {
 [[NSUserDefaults standardUserDefaults] removeObjectForKey:CLUserLanguageKey];
 [[NSUserDefaults standardUserDefaults] setValue:nil forKey:@"AppleLanguages"];
 [[NSUserDefaults standardUserDefaults] synchronize];
}

[CLLanguageManager setUserLanguage:@"en"];
 CLTabbarController *tabbarController = [[CLTabbarController alloc] init];
tabbarController.selectedIndex = 3;
UINavigationController *navigationController = tabbarController.selectedViewController;
NSMutableArray *viewControllers = navigationController.viewControllers.mutableCopy;
 //取出我的頁面，提前加載，解決返回按鈕不變化
 CLMyController *me = (CLMyController *)[viewControllers firstObject];
[me loadViewIfNeeded];
 //新建設(shè)置語言頁面
CLChangeLanguageController *languageController = [[CLChangeLanguageController alloc] init];
languageController.hidesBottomBarWhenPushed = YES;
[viewControllers addObject:languageController];
 //解決奇怪的動畫bug。
dispatch_async(dispatch_get_main_queue(), ^{
 [UIApplication sharedApplication].keyWindow.rootViewController = tabbarController;
 navigationController.viewControllers = viewControllers;
 CLLog(@"已切換到語言 %@", [NSBundle currentLanguage]);
});