隐藏的最常见的操作，置其为透明🤣

在TabBarVC里

- (void)viewDidLoad {
    [super viewDidLoad];
    
    YTTabBar *tabBar = [[YTTabBar alloc] init];
    tabBar.tbDelagete = self;
    [self setValue:tabBar forKeyPath:@"tabBar"];
    UIImage *bgImg = [UIImage imageWithColor:[UIColor clearColor] size:CGSizeMake(SCREEN_Width, TabBarHeight)];
    [self.tabBar setBackgroundImage:bgImg];
    [self.tabBar setShadowImage:bgImg];
}

修改分割线颜色

点xcode的Debug View Hierarchy可以看到,tabBar上有一条细线，其实就是一个超出父视图0.5像素的UIImageView。
那么，我们就可以置空tabbar的背景图和阴影，插入一个View，设成自己需要的颜色。

    [self.tabBar setBackgroundImage:[UIImage new]];
    [self.tabBar setShadowImage:[UIImage new]];
    
    UIView *view = [[UIView alloc] initWithFrame:CGRectMake(0, -0.5, SCREEN_Width, 0.5)];
    view.backgroundColor = HEXCOLOR(0xf5f5f5);
    [[UITabBar appearance] insertSubview:view atIndex:0];

达成目标😊。

给UIImage加的Category里

+ (UIImage *)imageWithColor:(UIColor *)color size:(CGSize)size{

    if (size.width == 0 || size.height == 0) {
        size = CGSizeMake(1, 1);
    }

    CGRect rect = CGRectMake(0, 0, size.width, size.height);
    UIGraphicsBeginImageContext(rect.size);
    CGContextRef context = UIGraphicsGetCurrentContext();
    CGContextSetFillColorWithColor(context,color.CGColor);
    CGContextFillRect(context, rect);
    UIImage *img = UIGraphicsGetImageFromCurrentImageContext();
    UIGraphicsEndImageContext();
    
    return img;
}