xcode 使用不兼容类型 'id<UIApplicationDelegate> _Nullable' 的表达式初始化 ' ... *__strong'
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Initialising ' ... *__strong' with an expression of incompatible type 'id<UIApplicationDelegate> _Nullable'
提问by RGriffiths
I have just updated my copy of Xcode and find that I now have lots of warnings. I am struggling to get the following one sorted out though:
我刚刚更新了我的 Xcode 副本，发现我现在有很多警告。不过，我正在努力解决以下问题：
ObAppDelegate *appdelegate = [[UIApplication sharedApplication]delegate];
causes this warning:
导致此警告：
Initializing
ObAppDelegate *__strongwith an expression of incompatible typeid<UIApplicationDelegate> _Nullable
ObAppDelegate *__strong用不兼容类型的表达式初始化id<UIApplicationDelegate> _Nullable
Can anyone point me in the right direction to fix this warning? For information this is the related code used prior to the problem line:
任何人都可以指出我解决此警告的正确方向吗？有关信息，这是在问题行之前使用的相关代码：
- (NSManagedObjectContext *) managedObjectContext {
return [(ObAppDelegate *) [[UIApplication sharedApplication] delegate] managedObjectContext];
}
回答by matt
You have:
你有：
ObAppDelegate *appdelegate = [[UIApplication sharedApplication]delegate];
This will give a warning:
这将发出警告：
Initializing
ObAppDelegate *__strongwith an expression of incompatible typeid<UIApplicationDelegate> _Nullable
ObAppDelegate *__strong用不兼容类型的表达式初始化id<UIApplicationDelegate> _Nullable
Rewrite as:
改写为：
ObAppDelegate *appdelegate = (ObAppDelegate*)[[UIApplication sharedApplication]delegate];
That will eliminate the warning.
这将消除警告。
