Question

我有一个带有按钮的主屏幕，当我们点击按钮显示登录屏幕时，用户通过电话号码登录，如果用户输入未注册的号码，则在屏幕上显示按钮前往注册表单屏幕，现在我正在尝试，如果用户已经登录，那么无论何时打开应用程序都不应该看到登录屏幕，它应该直接转到登录后出现的下一个屏幕，如果用户之前没有登录它应该显示登录屏幕。我的代码是，

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

UIStoryboard *storyBoard = [UIStoryboard storyboardWithName:@"Main" bundle:[NSBundle mainBundle]];

if([[NSUserDefaults standardUserDefaults] valueForKey:@"login"])
{
    // So, here user already login then set your root view controller, let's say `SecondViewController``
    HomeViewController *secondViewController = [storyBoard instantiateViewControllerWithIdentifier:@"HomeViewController"];
    // then set your root view controller
    self.window.rootViewController = secondViewController;
} else
{
    // It means you need to your root view controller is your login view controller, so let's create it
    RegisterViewController  *loginViewController= [storyBoard instantiateViewControllerWithIdentifier:@"RegisterD"];
    self.window.rootViewController = loginViewController;
}
// Override point for customization after application launch.
return YES;

}

Answer 1

将密钥的boolforkey insted值用作

 [[NSUserDefaults standardUserDefaults] boolForKey:@"login"]

Answer 2

您可以使用NSUserDefault设置当前用户登录状态。在下一个应用程序启动时，在主视图控制器上，当您单击该按钮时，在加载登录屏幕之前，请检查用户登录状态。如果是，则直接加载下一个屏幕，如果没有重定向到登录屏幕。

func loginButtonOnHomeScreen(sender:UIButton){
  let loginState = UserDefaults.standard.bool(forKey: "Login")
        var VC:UIViewController
        if loginState == true{
             VC = (self.storyboard?.instantiateViewController(withIdentifier: "NextScreen"))!
        }else{
            VC = (self.storyboard?.instantiateViewController(withIdentifier: "LoginScreen"))!
        }
        self.navigationController?.pushViewController(VC, animated: true)
}

希望这会有所帮助

编辑 n目标C

 BOOL loginState = [[NSUserDefaults  standardUserDefaults] boolForKey:@"Login"];
    UIViewController *VC;
    if (loginState == true){
        VC = [self.storyboard instantiateViewControllerWithIdentifier:@"NextScreen"];
    }else{
        VC = [self.storyboard instantiateViewControllerWithIdentifier:@"LoginScreen"];
    }
    [self.navigationController pushViewController:VC animated:true];

Answer 3

用户登录/注册成功设置

[[NSUserDefaults standardUserDefaults] setBool:YES forKey:@"login"];

当用户注销时从NSUserDefaults中删除或设置false

[[NSUserDefaults standardUserDefaults] removeObjectForKey:@"login"];

OR

[[NSUserDefaults standardUserDefaults] setBool:FALSE forKey:@"login"];

您可以在appDelegate文件或任何其他合适的屏幕中检查用户是否已登录

if([[NSUserDefaults standardUserDefaults] boolForKey:@"login"])
{
    //YES Already Login
    NextController *nextVC = [self.storyboard instantiateViewControllerWithIdentifier:@"NextController"];
}
else
{
    //NOT Login
    LoginController *loginVC = [self.storyboard instantiateViewControllerWithIdentifier:@"LoginController"];
}

Answer 4

你有2个ViewController（LoginVC和HomeVC），首先在＆＃34; LoginVC＆＃34;

中编写波纹管代码

if ([[NSUserDefaults standardUserDefaults] boolForKey:@"loggedIn"]){

   nslog(@"Success"};
 }
else{
    nslog(@"Login Agin")
 }

HomeVC中的第二个代码写入（此登录后）

-(void)viewWillAppear:(BOOL)animated{

  [[NSUserDefaults standardUserDefaults]setBool:YES forKey:@"loggedIn"];
}

用户已在IOS登录时跳过登录视图控制器

4 个答案: