iOS：更改背景幕后的视图不会刷新应用程序返回前台之前所看到的内容

Ok, I got this issue: I have an application with a login screen that is suposed to show everytime the app goes to background and return. The problem is, the previous screen appears for a fraction of second after the app return to foreground, because the system only refresh what is being seen after loading. What is need is a complete transition before the app returns to foreground. Yes, I am doing the transition on app delegate, at applicationDidEnterBackground. tried at every single other back/fore transition method, same results. The code works fine, but theres a flash of the screen before the login screen showing up.Ok, I got this issue: I have an application wit