2023-07-18 关于在View获取当前VC push 到

View 的Push 方法：

   if let tabVC = UIApplication.shared.keyWindow?.rootViewController as? UITabBarController,

        let navi = tabVC.selectedViewControlleras?UINavigationController{

            let playVC =BCPlayerViewController()

            playVC.hidesBottomBarWhenPushed = true

            navi.pushViewController(playVC,animated:true)

        }

问题：当在 BCPlayerViewController popViewController 回去时出现界面卡顿

原因：BCPlayerViewController 上添加了一个UIImageView ：

 bgImageView.frame = CGRectMake(0, 0,kScreenWidth, kScreenHeight)

 bgImageView.sd_setImage(with: NSURL(string: BCPlayerManager.shared.player?.songModel.albumimg ?? "") as URL?,       placeholderImage: UIImage(named: "lost_icon"))

bgImageView.contentMode = .scaleAspectFill

 view.addSubview(bgImageView)

 解决方式：在popViewController 之前，移除这个UIImageView

  bgImageView.removeFromSuperview()

   self.navigationController?.popViewController(animated: true)

另：真正的原因是这一句：bgImageView.sd_setImage(with: NSURL(string: BCPlayerManager.shared.player?.songModel.albumimg ?? "") as URL?,       placeholderImage: UIImage(named: "lost_icon")) 取消了就没事了。原因不明。