ios - 如何在Appdelegate中通过获取keyWindow来present一个UIViewAlertViewController

Question

1.问题描述

我想要在- (BOOL)application:(UIApplication )application didFinishLaunchingWithOptions:(NSDictionary )launchOptions中弹出present出一个UIViewAlertViewController，效果就是在启动页的时候弹出更新提示，但是因为当前的这个window还没有成为keyWindow，所以在启动页消失后，层次图就会变成下面这样。

是否只能等首页出现弹出UIAlertViewController才能正确的在keyWindow上弹出？

2.代码

[[UIApplication sharedApplication].keyWindow.rootViewController presentViewController:alertControler animated:YES completion:^{
                
}];

也使用过

UIWindow *window = [UIApplication sharedApplication].delegate.window;
[window makeKeyAndVisible];
[window.rootViewController presentViewController:alertControler animated:YES completion:^{
                
}];

3.请教

1.怎么样才是正确的姿势。。。
2.是否是因为当前的keyWindow和启动图过后出现首页时的keyWindow不同。（我觉得是这个原因）

Answer 1

According to your needs, you should operate in the startup page, not the entry class

Answer 2

Why not test it, print their addresses and see if they are the same?

Answer 3

Can’t I use navigation to push?

Answer 4

Why do you have to use keywindow? Can’t you use navigation controller or tabBarController?