GIF持续时间

Question

我正在按照Splash Screen中的以下代码在UIImageView中设置GIF。

let url = Bundle.main.url(forResource: "Splash", withExtension: "gif")

self.imgGifSplash.sd_setImage(with: url!, completed: { (img, error, type, url) in
     // this block is called when Gif is loaded in UIImageView, not when image is completed playing once.

          DispatchQueue.main.asyncAfter(deadline: .now() + 3.2) { // Change `2.0` to the desired number of seconds.

                    if let _ = UserData.shared.loginData?.token {
                        let VC = mainStoryboard.instantiateViewController(withIdentifier: "HomeVCNav") as! UINavigationController
                        objAppDelegate.window?.rootViewController = VC
                    }
                    else
                    {
                        let VC = mainStoryboard.instantiateViewController(withIdentifier: "LoginNav") as! UINavigationController
                        objAppDelegate.window?.rootViewController = VC
                    }
                }
}

我希望Gif只播放一次。所以我尝试使用3.2秒的计时器，但是当我使用不同的设备时，我得到了不同的结果，例如有时它只播放一次，有时播放两次，有时甚至不播放一次。

我如何获得一个只播放一次GIF的完美动画启动画面？

希望得到完美的答案。预先感谢。