ios轻松访问应用级属性

Question

我在AppDelegate有一个属性，我想轻松抓住。到目前为止，它并没有按计划为我工作：

[(AppDelegate *)[UIApplication sharedApplication] wasLoggedIn] = YES

AppDelegate.h

@property (nonatomic, assign) BOOL wasLoggedIn;

AppDelegate.m

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    wasLoggedIn = false;
}

我做错了什么？

Answer 1

[(AppDelegate *)[UIApplication sharedApplication] wasLoggedIn] = YES;

应该是

[(AppDelegate *)[[UIApplication sharedApplication] delegate] wasLoggedIn] = YES;

您此刻正在调用UIApplication实例上的方法。