NSBundle+MJRefresh.h 2020-11-17

//
//  NSBundle+MJRefresh.m
//  MJRefreshExample
//
//  Created by MJ Lee on 16/6/13.
//  Copyright © 2016年 小码哥. All rights reserved.
//

#import "NSBundle+MJRefresh.h"
#import "MJRefreshComponent.h"
#import "MJRefreshConfig.h"

@implementation NSBundle (MJRefresh)
+ (instancetype)mj_refreshBundle
{
    static NSBundle *refreshBundle = nil;
    if (refreshBundle == nil) {
        // 这里不使用mainBundle是为了适配pod 1.x和0.x
        refreshBundle = [NSBundle bundleWithPath:[[NSBundle bundleForClass:[MJRefreshComponent class]] pathForResource:@"MJRefresh" ofType:@"bundle"]];
    }
    return refreshBundle;
}

+ (UIImage *)mj_arrowImage
{
    static UIImage *arrowImage = nil;
    if (arrowImage == nil) {
        arrowImage = [[UIImage imageWithContentsOfFile:[[self mj_refreshBundle] pathForResource:@"arrow@2x" ofType:@"png"]] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
    }
    return arrowImage;
}

+ (UIImage *)mj_trailArrowImage {
    static UIImage *arrowImage = nil;
    if (arrowImage == nil) {
        arrowImage = [[UIImage imageWithContentsOfFile:[[self mj_refreshBundle] pathForResource:@"trail_arrow@2x" ofType:@"png"]] imageWithRenderingMode:UIImageRenderingModeAlwaysTemplate];
    }
    return arrowImage;
}

+ (NSString *)mj_localizedStringForKey:(NSString *)key
{
    return [self mj_localizedStringForKey:key value:nil];
}

+ (NSString *)mj_localizedStringForKey:(NSString *)key value:(NSString *)value
{
    static NSBundle *bundle = nil;
    if (bundle == nil) {
        NSString *language = MJRefreshConfig.defaultConfig.languageCode;
        // 如果配置中没有配置语言
        if (!language) {
            // （iOS获取的语言字符串比较不稳定）目前框架只处理en、zh-Hans、zh-Hant三种情况，其他按照系统默认处理
            language = [NSLocale preferredLanguages].firstObject;
        }
        
        if ([language hasPrefix:@"en"]) {
            language = @"en";
        } else if ([language hasPrefix:@"zh"]) {
            if ([language rangeOfString:@"Hans"].location != NSNotFound) {
                language = @"zh-Hans"; // 简体中文
            } else { // zh-Hant\zh-HK\zh-TW
                language = @"zh-Hant"; // 繁體中文
            }
        } else if ([language hasPrefix:@"ko"]) {
            language = @"ko";
        } else if ([language hasPrefix:@"ru"]) {
            language = @"ru";
        } else if ([language hasPrefix:@"uk"]) {
            language = @"uk";
        } else {
            language = @"en";
        }wenj 
        
        // 从MJRefresh.bundle中查找资源
        bundle = [NSBundle bundleWithPath:[[NSBundle mj_refreshBundle] pathForResource:language ofType:@"lproj"]];
    }
    // 此处获取了 value 为什么下面还需要再次获取
    value = [bundle localizedStringForKey:key value:value table:nil];

   // 1. 如果app 内 有 Localizable.strings  文件，注意名字必须是默认的Localizable.strings，则取对应的文本字符串
  // 2. 如果app 内没有  Localizable.strings  文件，取值如果 value 有值以 value 返回。如果value 没有，则以 key 返回
    return [[NSBundle mainBundle] localizedStringForKey:key value:value table:nil];
}
@end

如何实现国际化

https://www.cnblogs.com/whongs/p/6727610.html
https://blog.csdn.net/a787188834/article/details/101013322