iOS国际化中你可能会用到的一些小技巧

一：系统权限的提示语国际化

1. 在项目内新建名称为 InfoPlist.strings 的文件

2. 选好locallzation

3. 进入info.plist，选择show Raw keys提取key

4. 将key 写入InfoPlist.strings：

   NSAppleMusicUsageDescription = "You need to access media data to store pictures or videos.Do you allow access (yes or no)";
   NSMicrophoneUsageDescription = "Use a microphone to capture sound during live broadcast,Are you allowed to turn on the microphone.";
   NSPhotoLibraryAddUsageDescription = "You need to visit the album to select a picture,Do you allow access.";
   

二：LaunchScreen的国际化

很多时候我们也需要将启动页LaunchScreen国际化，可按照下面的步骤：

1. info.plist内写入key：Launch screen interface file base name(有就不要写了) value：LaunchScreen

2. 新建2个LaunchScree,名称为LaunchScreen_CH和LaunchScreen_EN

3. InfoPlist.strings内对应的语言文件写入

   UILaunchStoryboardName = "LaunchScreen_EN"; (英文)
   UILaunchStoryboardName = "LaunchScreen_CH"; (中文)
   

LaunchScreen本来是可以直接选好locallzation然后国际化的，但是现在应该是苹果的bug，locallzation之后只显示英文，所以我选择用这种创建两个LaunchScreen的方式

三：获取系统当前的语言

NSUserDefaults *defaults = [NSUserDefaults standardUserDefaults];
NSArray *languages = [defaults objectForKey:@"AppleLanguages"];

四：MJRefresh的多语言加载

MJRefresh中添加多语言可以根据具体的业务需求改动，全局搜索这个方法:

+ (NSString *)mj_localizedStringForKey:(NSString *)key value:(NSString *)value

五：设置APP语言的工具类

# import <Foundation/Foundation.h>

@interface NSBundle (Language)

+ (void)setLanguage:(NSString *)language;

@end

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

static const char _bundle = 0;

@interface BundleEx : NSBundle

@end

@implementation BundleEx

- (NSString *)localizedStringForKey:(NSString *)key value:(NSString *)value table:(NSString *)tableName {
    NSBundle *bundle = objc_getAssociatedObject(self, &_bundle);
    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], [BundleEx class]);
    });
    
    objc_setAssociatedObject([NSBundle mainBundle], &_bundle, language ? [NSBundle bundleWithPath:[[NSBundle mainBundle] pathForResource:language ofType:@"lproj"]] : nil, OBJC_ASSOCIATION_RETAIN_NONATOMIC);
}

@end

使用方法：

[NSBundle setLanguage:@"zh-Hans"];