导航栏 透明

    [self.navigationController.navigationBar  setTranslucent:YES];    UIColor * color = [UIColor clearColor];    CGRect rect = CGRectMake(0, 0, KEY_WINDOW.width, 64);    UIGraphicsBeginImageContext(rect.size);    CGContextRef context = UIGraphicsGetCurrentContext();    CGContextSetFillColorWithColor(context, [color CGColor]);    CGContextFillRect(context, rect);    UIImage * image = UIGraphicsGetImageFromCurrentImageContext();    UIGraphicsEndImageContext();    [self.navigationController.navigationBar setBackgroundImage:image forBarMetrics:UIBarMetricsDefault];    [self.navigationController.navigationBar setClipsToBounds:YES];