동적 변경 TabBar

UIImage+TabbarIcon.h

@interface UIImage (TabbarIcon)

/**
 BarItem.image
 @param imageUrl  
 @return image
 -------------------------------------
 nav.tabBarItem.image = [UIImage imageWithData:data]; ,Xcode @1x, tabBarItem 。
  ， ， @2x @3x，imageWithContentsOfFile: 

 icon ， ：@"https://gitee.com/Ccfax/HunterPrivateImages/raw/master/[email protected]" @2x， @3x 。
 */
+ (UIImage *)barItemImage:(NSString *)imageUrl;

@end

UIImage+TabbarIcon.m

#import "UIImage+TabbarIcon.h"

@implementation UIImage (TabbarIcon)

+ (UIImage *)barItemImage:(NSString *)imageUrl{
    NSArray *stringArr = [imageUrl componentsSeparatedByString:@"/"];
    NSString *imageName = stringArr.lastObject;
    NSData *data = [NSData dataWithContentsOfURL:[NSURL URLWithString:imageUrl]];
    UIImage *image = [UIImage imageWithData:data];
    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSCachesDirectory,NSUserDomainMask,YES);
    NSString *filePath = [[paths objectAtIndex:0] stringByAppendingPathComponent:imageName];
    //  ， ， 
    if ([[NSFileManager defaultManager] fileExistsAtPath:filePath]) {
        [[NSFileManager defaultManager] removeItemAtPath:filePath error:nil];
    }
    //  image 
    [UIImagePNGRepresentation(image) writeToFile:filePath atomically:YES];
    return [UIImage imageWithContentsOfFile:filePath];
}

@end