Question

我正在尝试加载一个viewController，如果没有帐户登录但是它给了我这个错误Warning: Attempt to present <DefaultViewController: 0xb96cac0> on <MainViewController: 0xb95c320> whose view is not in the window hierarchy! 这是我现在使用的代码：

BOOL returnAllOff = [[User data] returnAllOff];

if (returnAllOff) {
    DefaultViewController *viewController =[[DefaultViewController alloc]
    init];
    UIViewController *presentingController = [[[[UIApplication sharedApplication] delegate] window] rootViewController];
    [presentingController presentViewController:viewController animated:YES completion:nil];

}

Answer 1

实际上这是从AppDelegate加载ViewController的正确方法..

    self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];

    DefaultViewController *viewController = [[DefaultViewController alloc] initWithNibName:@"DefaultViewController" bundle:nil];
    self.window.rootViewController = viewController;
    [self.window makeKeyAndVisible];

Answer 2

通过在appDElegate中导入DefaultViewController来试试这个。

self.window = [[UIWindow alloc] initWithFrame:[[UIScreen mainScreen] bounds]];
DefaultViewController *viewController = [[DefaultViewController alloc] init];
self.window.rootViewController = viewController;
[self.window makeKeyAndVisible];

视图控制器未在App Delegate中显示

2 个答案: