IOS:如何在第一次登录 ios 时处理 View Controller

Question

当我第一次进入登录屏幕时，我将值存储在 NSUserDefaults .当我按下 signinButtonAction移至 DetailScreen它卡住了，永远不会前进。
我做了DetailScreen嵌入 Navigationcontroller如InitialViewController当我再次重新运行它时，即使下一个屏幕也没有导航到其他屏幕，它涉及 DetailScreen然后 DetailScreen卡住导航到其他屏幕。

我该如何处理？

我的代码在这里:
AppDelegate

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

    if ([[NSUserDefaults standardUserDefaults] objectForKey:@"email"])
    {
        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];

        categoryVC *viewController = (categoryVC *)[storyboard instantiateViewControllerWithIdentifier:@"categoryVC"];
        [self.window setRootViewController:viewController];
    }
    else
    {
        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];

        signInVC *viewController = (signInVC *)[storyboard instantiateViewControllerWithIdentifier:@"signInVC"];
        [self.window setRootViewController:viewController];
    }

在 SigninButtonAction我在做:

{
    categoryVC * second= [self.storyboard instantiateViewControllerWithIdentifier:@"categoryVC"];

    [self.navigationController pushViewController:second animated:YES];
}

Answer 1

我不会设置 RootViewController如果你有这样的工作流程。我会按原样实例化主视图 Controller ，如果您需要显示身份验证，我会使用 presentViewController .稍后，您可以执行解雇或类似的操作。

因此，在您的应用程序委托(delegate)中:

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    if (nil == [[NSUserDefaults standardUserDefaults] objectForKey:@"email"])
    {
        UIStoryboard *storyboard = [UIStoryboard storyboardWithName:@"Main" bundle:nil];
        categoryVC *viewController = (categoryVC *)[storyboard instantiateViewControllerWithIdentifier:@"signInVC"];
        [self.window.rootViewController presentViewController:viewController animated:NO];
    }
}

然后，当您进行身份验证并通过时:

[self dismissViewControllerAnimated:TRUE completion:nil];