导航栏渐变完美适配ipone - x 齐刘海

- (void)colorGradientStartColor:(UIColor *)startPoint endColor:(UIColor *)endColor
{
    NSArray * subs  =[self.navigationBar subviews];
    UIView  * bgview=nil;
    
    for (UIView  * v in subs)
    {
        NSString * classname = NSStringFromClass([v class]);
        if ([classname isEqualToString:@"_UIBarBackground"] || [classname isEqualToString:@"UIBarBackground"])
        {
            bgview=v;
            break;
        }
    }
    
    //初始化CAGradientlayer对象，使它的大小为UIView的大小
    CAGradientLayer *gradientLayer = [CAGradientLayer layer];
    CGRect rect = bgview.frame;
    rect.size.height = [UIScreen statusAndNavigationBarHeight];
    bgview.frame = rect;
    
    gradientLayer.frame = bgview.frame;
    
    //将CAGradientlayer对象添加在我们要设置背景色的视图的layer层
    //    [self.navigationController.navigationBar.layer addSublayer:gradientLayer];
    [bgview.layer addSublayer:gradientLayer];
    
    
    
    
    //设置渐变区域的起始和终止位置（范围为0-1）
    gradientLayer.startPoint = CGPointMake(0, 0);
    gradientLayer.endPoint = CGPointMake(1, 0);
    
    //设置颜色数组
    gradientLayer.colors = @[(__bridge id)startPoint.CGColor,
                             (__bridge id)endColor.CGColor];
    
    //设置颜色分割点（范围：0-1）
    gradientLayer.locations = @[@(0.1f), @(1.0f)];
    
    
    //隐藏黑线
    [self.navigationBar setShadowImage:[UIImage new]];
}