graceTime和- (void)hideAnimated:(BOOL)animated afterDelay:(NSTimeInterval)delay 冲突。

   MBProgressHUD *HUD = [[MBProgressHUD alloc] initWithView:view];        HUD.removeFromSuperViewOnHide = YES;
    HUD.graceTime = 0.25;
    [view addSubview:HUD];
    [HUD showAnimated:YES];
    [HUD hideAnimated:YES afterDelay:3];

当设置了graceTime，延迟隐藏hud失效。
MBProgressHud版本号：1.1.0