objective-c - appdelegate 共享实例委托(delegate)

Question

    MyAppDelegate *appD;        
    appD = [UIApplication sharedApplication];

    if(appD.sw1.on)
        NSLog(@"It is ON");
    else
        NSLog(@"It is OFF");

编译时没有报错。在没有任何警告的情况下运行，但它不起作用。

我不明白是什么问题。

...

编辑:我的天啊，也应该调用委托(delegate)方法:

appD = (MyAppDelegate *)[[UIApplication sharedApplication] delegate];

Answer 1

我向您推荐这种方法来共享应用委托(delegate): https://coderwall.com/p/z4h4uw?i=2&p=1&q=&t%5B%5D=%21%21mine&t%5B%5D=%21%21bookmarks