在appdelegate.m文件中找不到viewcontroller

Question

我正在按照ios教程将Facebook纳入我的应用程序.一切都很顺利,直到我得到关于添加注销按钮的部分.我一直收到一个错误,说明在类型的对象上找不到属性"ViewController".我究竟做错了什么？这是我的appdelegate.m文件中的代码.

-(BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {    

    // Add the requests dialog button
    UIButton *requestDialogButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    requestDialogButton.frame = CGRectMake(40, 150, 200, 40);
    [requestDialogButton setTitle:@"Send Request" forState:UIControlStateNormal];
    [requestDialogButton addTarget:self 
                            action:@selector(requestDialogButtonClicked)
                  forControlEvents:UIControlEventTouchUpInside];
    [self.viewController.view addSubview:requestDialogButton];
    // ...
}

Answer 1

你在标题中声明viewController了类型UIViewController并合成了吗？它看起来你正在做你的工作AppDelegate,我建议反对.你应该在你实现这个viewcontrollers' viewDidLoad:或viewWillAppear:方法.