I create launchScreen for pause view like this.
func applicationWillResignActive(_ application: UIApplication) {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let launchScreen = storyboard.instantiateViewController(withIdentifier: "launchScreen")
launchScreen.restorationIdentifier = "launchScreen"
var rootViewController = UIApplication.shared.keyWindow?.rootViewController
while let presentController = rootViewController?.presentedViewController {
rootViewController = presentController
}
rootViewController?.present(launchScreen, animated: false, completion: nil)
}
func applicationDidEnterBackground(_ application: UIApplication) {
guard let passcodeManageView = UIStoryboard(name: "Main", bundle: nil).instantiateViewController(withIdentifier: "passcodeManageView") as? PasscodeManageViewController else { return }
passcodeManageView.state = State.loginMode
passcodeManageView.modalPresentationStyle = .overFullScreen
var rootViewController = UIApplication.shared.keyWindow?.rootViewController
while let presentController = rootViewController?.presentedViewController {
rootViewController = presentController
}
rootViewController?.present(passcodeManageView, animated: false, completion: nil)
}
But, How to dismiss launchScreen in applicationDidEnterBackground(:_)??
How can I find specific view controller and that dismiss??
According to Apple document for applicationDidEnterBackground(_:)`
Use this method to release shared resources, invalidate timers, and store enough app state information to restore your app to its current state in case it is terminated later. You should also disable updates to your app’s user interface and avoid using some types of shared system resources (such as the user’s contacts database). It is also imperative that you avoid using OpenGL ES in the background.
You shouldn't dismiss launch screen after app entered background. But if you still want to achieve it, use window?.rootViewController? to dismiss because at this time, window?.rootViewController? is launch screen
func applicationDidEnterBackground(_ application: UIApplication) {
if (window?.rootViewController?.isKind(of: YOUR_LAUNCH_SCREEN_CLASS.self))! {
window?.rootViewController?.dismiss(animated: true, completion: nil)
}
}
Related
I need to present different UIViewController on the launch of my app. I have a "login" page for the user to interact with. Once the user logs in or creates an account it takes to a different UIViewController with a map to interact with. I've looked online and so far I know that we should do it within AppDelegate.swift file. I have not completed the statement whether or not the user has logged in since I am still running into some errors
AppDelegate
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
Thread.sleep(forTimeInterval: 2.0)
window = UIWindow(frame: UIScreen.main.bounds)
window?.makeKeyAndVisible()
window?.rootViewController = MainNavigationContoller()
return true
}
I also have another swift file with MainNavigationContoller that should call the mainviewController
override func viewDidLoad() {
super.viewDidLoad()
let isloggedIn = false
if isloggedIn == false {
self.present(mainViewController(), animated: true, completion: nil)
} else {
self.present(mapViewController(), animated: true, completion: nil)
}
}
The app launches with the launchScreen but then sends errors to mainViewController such as Thread 1: Fatal error: Unexpectedly found nil while implicitly unwrapping an Optional value
You are not instantiating the View Controllers properly.
Here is a function that I use to make a root view controller, put this into your AppDelegate.
func makeRootVC(storyBoardName : String, vcName : String) {
let vc = UIStoryboard(name: storyBoardName, bundle: Bundle.main).instantiateViewController(withIdentifier: vcName)
let nav = UINavigationController(rootViewController: vc)
nav.navigationBar.isHidden = true
self.window?.rootViewController = nav
let options: UIView.AnimationOptions = .transitionCrossDissolve
let duration: TimeInterval = 0.6
UIView.transition(with: self.window!, duration: duration, options: options, animations: {}, completion: nil)
}
Now in your Appdelegate, replace your code with this:
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
Thread.sleep(forTimeInterval: 2.0)
self.makeRootVC(storyboardName: "Main", vcName : "YourVCStoryboardId")
return true
}
and in your MainNavigationController,
override func viewDidLoad() {
super.viewDidLoad()
let isloggedIn = false
let appDelegateObj = UIApplication.shared.delegate as! AppDelegate
if isloggedIn == false {
appDelegateObj.makeRootVC(storyboardName: "Main", vcName: "mainViewController")
} else {
appDelegateObj.makeRootVC(storyboardName: "Main", vcName: "mapViewController")
}
}
NOTE: Open storyboard and give every controller a StoryboardID. What I prefer is naming them the same as ViewController's name as it is easy to remember. and in vcName, we need to pass the storyboarID of the controller we want to present.
UPDATE:
Above code is for making a root view controller, if you want to push controllers, you can use this code instead:
extension UIViewController {
func pushVC(storyboardName : String, vcname : String) {
let vc = UIStoryboard.init(name: storyboardName, bundle: Bundle.main).instantiateViewController(withIdentifier: vcname)
vc.hidesBottomBarWhenPushed = true
self.navigationController?.pushViewController(vc, animated: true)
}
}
In your MainNavigationController if instead of making root view controllers in viewDidLoad, you want to just push the controller, then use the above code like this:
override func viewDidLoad() {
super.viewDidLoad()
let isloggedIn = false
if isloggedIn == false {
self.pushVC(storyboardName: "Main", vcName: "mainViewController")
} else {
self.pushVC(storyboardName: "Main", vcName: "mapViewController")
}
}
I've set up a UIViewController as my rootViewController in AppDelegate, however, when a user logs in or skips it I am presenting a UITabBarController over the top.
I need to dismiss the LoginController, and set the UITabController as rootViewController instead after user logs in.
How can I go about reorganizing this?
AppDelegate()
window = UIWindow()
window?.makeKeyAndVisible()
window?.rootViewController = LoginController()
LoginController()
self.present(MainTabBarController(), animated: true, completion: nil)
you can design your code like this.
This one
It's too easy to maintain condition for user logged in or not, and then based on that status. You can navigate to your view.
You can try this way :
1.In AppDelegate you can these methods.
func application(_ application: UIApplication, didFinishLaunchingWithOptions launchOptions: [UIApplication.LaunchOptionsKey: Any]?) -> Bool {
// Override point for customization after application launch.
let isLogin = UserDefaults.standard.bool(forKey: "IS_LOGIN")
if isLogin == true {
self.goToDashboardView()
} else {
self.goToLoginView()
}
return true
}
//MARK:- ------- Global Methods -------
class func sharedInstance() -> AppDelegate {
return UIApplication.shared.delegate as! AppDelegate
}
func goToLoginView() {
let sb = UIStoryboard.init(name: "Main", bundle: nil)
let loginVC = sb.instantiateViewController(withIdentifier: "LoginViewController") as! LoginViewController
let navVC = UINavigationController(rootViewController: loginVC) // You can skip this if you do not want to add navigation bar
self.window?.rootViewController = navVC // if you skipped above line, then you have to assign 'loginVC' here.
self.window?.makeKeyAndVisible()
}
func goToDashboardView() {
let sb = UIStoryboard.init(name: "Main", bundle: nil)
let tabbarVC = sb.instantiateViewController(withIdentifier: "MyTabBarController") as! MyTabBarController
self).window?.rootViewController = tabbarVC // if you skipped above line, then you have to assign 'loginVC' here.
self.window?.makeKeyAndVisible()
}
2.In LoginViewController, when user logged in successfully.
#IBAction func btnLoginClicked(_ sender: UIButton) {
// Your API call or other code
// If all things goes well, then login and go to dashboard
UserDefaults.standard.set(true, forKey: "IS_LOGIN")
AppDelegate.sharedInstance().goToDashboardView()
}
3.And finally, whenever and from wherever you want to log out from app, just call below code.
#IBAction func btnLogOutClicked(_ sender: UIButton) {
// Your API call or other code
// If all things goes well, then logout and go to login view
UserDefaults.standard.set(false, forKey: "IS_LOGIN")
AppDelegate.sharedInstance().goToLoginView()
}
4.And Main.storyboard should have design something like :
you do not need to present the UITabBarViewController and then dismiss the LoginViewController, you just need to reset the UITabBarViewController as a rootViewController for you app after login or skip as the following:
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
// Override point for customization after application launch.
let yourTabBar = UIStoryboard(name: "YOUR_STORYBOARD_NAME", bundle: nil).instantiateViewController(withIdentifier: "YOUR_UITABBARCONTROLLER_ID")
self.window!.rootViewController = yourTabBar
self.window!.makeKeyAndVisible()
return true
}
I am for some reason having some troubles figuring out the Shortcut Items in my app. I have followed all the tutorials and I believe that I have done everything right; however, it is acting really weird. The problem is that when you completely close out that app and do the 3D Touch Shortcut item on the home screen, it takes you to the correct part of the app as it should; however, when the app is open in the background (like you just click the home button) it doesn't take you to the correct part of the app, it just opens it. This is really odd and I am not sure what to do because I have followed all the instructions. Thank you so much!
Code:
func application(_ application: UIApplication, performActionFor shortcutItem: UIApplicationShortcutItem, completionHandler: #escaping (Bool) -> Void) {
if shortcutItem.type == "com.myapp.newMessage" {
let sb = UIStoryboard(name: "Main", bundle: nil)
let vc = sb.instantiateViewController(withIdentifier: "RecentVC") as! UITabBarController
vc.selectedIndex = 2 //this takes me to the contacts controller
let root = UIApplication.shared.keyWindow?.rootViewController
root?.present(vc, animated: false, completion: {
completionHandler(true)
})
} else if shortcutItem.type == "com.myapp.groups" {
let sb = UIStoryboard(name: "Main", bundle: nil)
let vc = sb.instantiateViewController(withIdentifier: "RecentVC") as! UITabBarController
vc.selectedIndex = 1 //this takes me to the groups controller
let root = UIApplication.shared.keyWindow?.rootViewController
root?.present(vc, animated: false, completion: {
completionHandler(true)
})
} else {
//more short cut items I will add later
}
}
NOTE: these are static Shortcut Items, and I configured them in the info.plist file, This function that was presented is the only place in the app besides the info.plist file that have anything about the Shortcut Items.
EDIT: This seems like an issue with the RootViewController, because I have tried multiple different ways of doing this, and it still gives me the same warning message
2017-11-22 22:36:46.473195-0800 QuickChat2.0[3055:1068642] Warning: Attempt to present on whose view is not in the window hierarchy!
I just tried to accomplish my goals this way through this post but it gives me the exact same results as before.
You should set a variable in your performActionForShortcutItem that tells you the shortcut type and move the code you have in there into applicationDidBecomeActive. Your could should look like this
var shortcut: String?
func applicationDidBecomeActive(application: UIApplication) {
if let shortcutItem = shortcut {
shortcut = nil
if shortcutItem == "com.myapp.newMessage" {
let sb = UIStoryboard(name: "Main", bundle: nil)
let vc = sb.instantiateViewController(withIdentifier: "RecentVC") as! UITabBarController
vc.selectedIndex = 2 //this takes me to the contacts controller
let root = UIApplication.shared.keyWindow?.rootViewController
root?.present(vc, animated: false, completion: nil)
} else if shortcutItem == "com.myapp.groups" {
let sb = UIStoryboard(name: "Main", bundle: nil)
let vc = sb.instantiateViewController(withIdentifier: "RecentVC") as! UITabBarController
vc.selectedIndex = 1 //this takes me to the groups controller
let root = UIApplication.shared.keyWindow?.rootViewController
root?.present(vc, animated: false, completion: nil)
} else {
//more short cut items I will add later
}
}
}
func application(_ application: UIApplication, performActionFor shortcutItem: UIApplicationShortcutItem, completionHandler: #escaping (Bool) -> Void) {
shortcut = shortcutItem.type
completionHandler(true)
}
I think a cleaner method is to set your flags in the performActionFor method, then check for them once your VC loads. Using this notification will handle the shortcut every time the app becomes active, including launch.
override func viewDidLoad() {
super.viewDidLoad()
// Sends notification if active app is reentered to handle quick actions
NotificationCenter.default.addObserver(self, selector: #selector(handleQuickActions), name: UIApplication.didBecomeActiveNotification, object: nil)
I am creating an app for iOS and I want to open a page view controller (not a normal view controller) but only the first time that a user opens the application.
The problem is that I can't open a new page view controller within the code. The first screen that the users will see is the login screen, but on first visit switch to the page view controller.
This is what I have so far in the login screen viewcontroller:
override func viewDidLoad() {
super.viewDidLoad()
// Do any additional setup after loading the view, typically from a nib.
let launchedBefore = NSUserDefaults.standardUserDefaults().boolForKey("launchedBefore")
if launchedBefore {
//Not the first time, show login screen.
}
else {
NSUserDefaults.standardUserDefaults().setBool(true, forKey: "launchedBefore")
//First time, open a new page view controller.
}
let secondViewController:InstructionViewController = InstructionViewController()
self.presentViewController(secondViewController, animated: true, completion: nil)
}
The page view controller that I want to open is already created on the storyboard.
App delegate's willFinishLaunchingWithOptions method would be the best place (AFAIK). check the condition and set window's root view controller accordingly.
With the other answers I was able to solve the problem.
In the appDeligate file you need to replace the first function with this:
var window: UIWindow?
var storyboard:UIStoryboard?
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
window = UIWindow(frame: UIScreen.mainScreen().bounds)
window?.makeKeyAndVisible()
let launchedBefore = NSUserDefaults.standardUserDefaults().boolForKey("launchedBefore")
if launchedBefore {
//Not the first time, show login screen.
storyboard = UIStoryboard(name: "Main", bundle: nil)
let rootController = storyboard!.instantiateViewControllerWithIdentifier("Login")
if let window = self.window {
window.rootViewController = rootController
}
}
else {
NSUserDefaults.standardUserDefaults().setBool(true, forKey: "launchedBefore")
//First time, open a new page view controller.
storyboard = UIStoryboard(name: "Main", bundle: nil)
let rootController = storyboard!.instantiateViewControllerWithIdentifier("Instruction")
if let window = self.window {
window.rootViewController = rootController
}
}
return true
}
"Login" and "Instruction" are the names of the (page) view controllers.
I am not sure if this is most robust code but it works fine for me.
Here is Lesley's code updated to Swift 3:
window = UIWindow(frame: UIScreen.main.bounds)
window?.makeKeyAndVisible()
let launchedBefore = UserDefaults.standard.bool(forKey: "launchedBefore")
if launchedBefore {
//Not the first time, show login screen.
storyboard = UIStoryboard(name: "Main", bundle: nil)
let rootController = storyboard!.instantiateViewController(withIdentifier: "webView")
if let window = self.window {
window.rootViewController = rootController
}
}
else {
UserDefaults.standard.set(true, forKey: "launchedBefore")
//First time, open a new page view controller.
storyboard = UIStoryboard(name: "Main", bundle: nil)
let rootController = storyboard!.instantiateViewController(withIdentifier: "progressView")
if let window = self.window {
window.rootViewController = rootController
}
}
Don't forget to set the
var storyboard:UIStoryboard?
Before didFinishLaunchingWithOptions, and to set the identifiers similar to your own view controllers identifiers.
I am developing an iOS App that has several Tabs. So I decided my root view Controller will be a Tab Bar Controller with 2 views.
I need the user to login as soon as the application starts, so I'm trying to find out the best approach to do this.
Following other similar questions posted here I've tried this 2 approaches:
Presenting the login screen as a Modal View on top of the Tab Bar Controller
Instantiating the Login view controller
I've done this, by using a UserisLoggedIn flag in NSUserDefaults that is set every time the user logs in or logs out.
The problem I face with both approaches is that before the login screen appears there's a quick flickr of the first view in the Tab Bar.
I've tried to resolve this setting the alpha value of the Tab Bar to 0 if the user is not logged in for the modal approach, but for the instance approach it doesnt work, it still flickers before showing the login screen. Anyway, I find this solution tedious and not really elegant.
There must be a standard approach for doing this in iOS, since you have loads of apps that present first a login screen, but since I am a beginner with iOS Programming I still don't know how to do it.
Here's some code from my Tab bar controller:
1st Approach
Tab Bar Controller
override func viewDidLoad() {
super.viewDidLoad()
view.alpha = 0
let defaults = NSUserDefaults.standardUserDefaults()
if defaults.objectForKey("userLoggedIn") as NSString == "loggedIn"{
view.alpha = 1.0
}
}
override func viewDidAppear(animated: Bool) {
super.viewDidAppear(false)
self.showLoginView()
}
func showLoginView(){
let defaults = NSUserDefaults.standardUserDefaults()
if defaults.objectForKey("userLoggedIn") == nil{
self.performSegueWithIdentifier("loginView", sender: self)
}
}
Login View Controller
func updateUserLoggedInFlag() {
// Update the NSUserDefaults flag
let defaults = NSUserDefaults.standardUserDefaults()
defaults.setObject("loggedIn", forKey: "userLoggedIn")
defaults.synchronize()
}
#IBAction func login(sender: AnyObject) {
//Do my login here...
//If login successful:
self.performSegueWithIdentifier("dismissLogin", sender: self)
}
2nd Approach, Creating an Instance of the Login View Controller
1st View in the Tab Bar
override func viewDidAppear(animated: Bool){
super.viewDidAppear(true)
let defaults = NSUserDefaults.standardUserDefaults()
if defaults.objectForKey("userLoggedIn") == nil{
let loginController: LoginViewController = self.storyboard?.instantiateViewControllerWithIdentifier("LoginViewController") as LoginViewController
self.tabBarController?.presentViewController(loginController, animated: false, completion: nil)
}
Login View Controller
#IBAction func login(sender: AnyObject) {
//Do my login here...
//If login successful:
self.dismissViewControllerAnimated(true, completion: nil)
}
OK here is what did the trick for me. I don't know if it's the right thing to do, but it seems to work. Like Joseph Duffy mentioned all I did was to set the Login view as the rootviewcontroller in the delegate, and once I was succesfully logged in, switch back to the tab bar controller as rootviewcontroller.
Code in AppDelegate:
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
let defaults = NSUserDefaults.standardUserDefaults()
if defaults.objectForKey("userLoggedIn") == nil{
showLogin()
}
}
func showLogin() {
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let loginViewController = storyboard.instantiateViewControllerWithIdentifier("LoginViewController") as LoginViewController
self.window?.makeKeyAndVisible()
self.window?.rootViewController = loginViewController
}
Code in LoginViewController
#IBAction func login(sender: AnyObject) {
//Do my login here...
//If login successful:
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let appDelegate: AppDelegate = UIApplication.sharedApplication().delegate as AppDelegate
self.dismissViewControllerAnimated(true, completion: nil)
appDelegate.window?.rootViewController = storyboard.instantiateViewControllerWithIdentifier("tabBarID") as TabBarController
}
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
// Override point for customization after application launch.
let defaults = NSUserDefaults.standardUserDefaults()
if defaults.objectForKey("userLoggedIn") == nil{
showLoginView()
}
func showLoginView(){
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let loginViewController: LoginViewController = storyboard.instantiateViewControllerWithIdentifier("LoginViewController") as LoginViewController
self.window?.makeKeyAndVisible()
self.window?.rootViewController?.presentViewController(loginViewController, animated: true, completion: nil)
}
Take a look at a similar question's answer. The solution is to do this check in your app delegate's application:didFinishLaunchingWithOptions: method by checking if the user is logged in and loading the login view from a storyboard when necessary.
I have created a blank project, added a view controller with a storyboard identifier of loginScreen and have the following code in the app delegate:
func application(application: UIApplication, didFinishLaunchingWithOptions launchOptions: [NSObject: AnyObject]?) -> Bool {
// Override point for customization after application launch.
self.showLogin()
return true
}
func showLogin() {
//loginScreen
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let loginViewController = storyboard.instantiateViewControllerWithIdentifier("loginScreen") as UIViewController
if let window = self.window {
window.makeKeyAndVisible()
window.rootViewController?.presentViewController(loginViewController, animated: false, completion: nil)
}
}
This shows the login screen and the main screen is not seen.