I use this code to open a new ViewController:
// Get a random next post
#IBAction func buttonNextPostTapped(_ sender: UIButton) {
let postNumber = Int.random(in: 0 ..< postIds.count)
let postId = postIds[postNumber]
PostApi.shared.getPost(postId: postId) { (post) in
let storyBoard : UIStoryboard = UIStoryboard(name: "MainApplication", bundle: nil)
let nextViewController = storyBoard.instantiateViewController(withIdentifier: "PostsViewController") as! PostsViewController
nextViewController.post = post
nextViewController.isFromRandom = true
self.present(nextViewController, animated: true, completion: {})
}
}
This code will open the same ViewController with different data. It works, however, the "old" ViewControllers will stack in the background. So if I open 10 new ViewControllers, I have 10 VC in the background.
How can I present a new ViewController, and dismiss the "old" one?
Using setViewControllers function from UINavigationController is the best way.
func setViewControllers(_ viewControllers: [UIViewController], animated: Bool)
And you can remove whichever controller you want to from stack like
if var navigationControllersArray:Array = (self.navigationController?.viewControllers) {
navigationControllersArray.remove(at: navigationControllersArray.count-2)
self.navigationController?.viewControllers = navigationControllersArray
}
Related
I have some problems displaying a viewcontroller in my IOS app.
Sometimes it works and the view is displayed, but sometimes and I guess when the context is a bit different it will not work. No errors or warnings in the debugger and it can find the ViewController from the Main storyboard (at least it is not nil)
It use to work with self.present but that seems not to work anymore.
#IBAction func showHistoryButton(_ sender: MDCButton) {
let exercisesHistoryVC = ExercisesHistoryViewController.instantiate(from: .Main)
exercisesHistoryVC.modalPresentationStyle = .fullScreen
let appDeligate = UIApplication.shared.delegate as! AppDelegate
appDeligate.window?.rootViewController!.present(exercisesHistoryVC,animated: true,completion: nil)
// parent?.present(exercisesHistoryVC, animated: true, completion: nil)
}
Use the code like below,while Present New View Controller
#IBAction func showHistoryButton(_ sender: MDCButton) {
let exercisesHistoryVC = ExercisesHistoryViewController.instantiate(from: .Main)
exercisesHistoryVC.modalPresentationStyle = .fullScreen
UIApplication.topViewController()?.present(exercisesHistoryVC, animated: false, completion: nil)
}
extension UIApplication {
static func topViewController(base: UIViewController? = UIApplication.shared.delegate?.window??.rootViewController) -> UIViewController? {
if let nav = base as? UINavigationController {
return topViewController(base: nav.visibleViewController)
}
if let tab = base as? UITabBarController, let selected = tab.selectedViewController {
return topViewController(base: selected)
}
if let presented = base?.presentedViewController {
return topViewController(base: presented)
}
return base
}
}
I am having a little problem with a segue in my application.
When I try to push a segue so that it has a navbar it shows up correctly in the storyboard but not when I try it on my iPhone.
This is an overview of a couple of view controllers where my problem lays.
This is supposed to be the segue, so you can see that it has a navigation bar and is correctly positioned on the storyboard.
This is the view on the iPhone. No navigation bar or nothing. I tried everything but can't seem to find a solution to this problem.
Does anyone what the problem could be?
A little extra side information:
I don't know if may have something to do with the problem but the navigation view controller is not always present only when the user is logged in the app. this is decided on a log in screen if the user is not logged in the user will see a normal login screen. Else it will go to navigation view controller with a view did appear function and self.present.
Here is the code that handles that action.
// Sees if the user is logged, If yes --> go to the account detail page else go to the account view.
override func viewDidAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let data = UserDefaults.standard.data(forKey: "User") {
do {
// Create JSON Decoder
let decoder = JSONDecoder()
// Decode Note
_ = try decoder.decode(User.self, from: data)
guard let loginVC = UIStoryboard.init(name: "Main", bundle: Bundle.main).instantiateViewController(withIdentifier:
"AccountDetailViewController") as? AccountDetailViewController else { return }
loginVC.modalPresentationStyle = .overCurrentContext
self.present(loginVC, animated: false, completion: {})
} catch {
print("Unable to Decode Note (\(error))")
}
}
}
You should push view controller instead of present. Please check this article to know more about Pushing, Popping, Presenting, & Dismissing ViewControllers
You can push AccountDetailViewController without segues. And you don't need to call performSegue(withIdentifier:) into tableView's didSelect function.
Remove segue from Interface Builder
let navigator = UINavigationController()
guard let loginVC = UIStoryboard(name: "Main", bundle: Bundle.main).instantiateViewController(withIdentifier:
"AccountDetailViewController") as? AccountDetailViewController else { return }
loginVC.modalPresentationStyle = .overCurrentContext
navigator.pushViewController(loginVC, animated: true)
After succesful login, you are presenting AccountDetailViewController without adding it in a navigation controller. I would suggest you to use these extensions that i created.
extension UIViewController {
func pushVC(vcName : String) {
let vc = UIStoryboard.init(name: "Main", bundle: Bundle.main).instantiateViewController(withIdentifier: vcName)
vc.hidesBottomBarWhenPushed = true
self.navigationController?.pushViewController(vc, animated: true)
}
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)
}
func popVC() {
self.navigationController?.popViewController(animated: true)
}
func makeRootVC(storyBoardName : String, vcName : String) {
let appDelegate = UIApplication.shared.delegate as! AppDelegate
let vc = UIStoryboard(name: storyBoardName, bundle: Bundle.main).instantiateViewController(withIdentifier: vcName)
let nav = UINavigationController(rootViewController: vc)
nav.navigationBar.isHidden = true
appDelegate.window?.rootViewController = nav // If using XCode 11 and above, copy var window : UIWindow? in your appDelegate file
let options: UIView.AnimationOptions = .transitionCrossDissolve
let duration: TimeInterval = 0.6
UIView.transition(with: appDelegate.window!, duration: duration, options: options, animations: {}, completion: nil)
}
}
Now in your case, when a user logs in, you should change your root view controller to AccountDetailViewController. So first, copy paste the above extension anywhere in your file and then use it like this:
// Sees if the user is logged, If yes --> go to the account detail page else go to the account view.
override func viewDidAppear(_ animated: Bool) {
super.viewWillAppear(animated)
if let data = UserDefaults.standard.data(forKey: "User") {
do {
// Create JSON Decoder
let decoder = JSONDecoder()
// Decode Note
_ = try decoder.decode(User.self, from: data)
self.makeRootVC(storyBoardName : "Main", vcName :"AccountDetailViewController")
} catch {
print("Unable to Decode Note (\(error))")
}
}
}
I used 'LGSideMenuController' in my project. but it cannot open from my all viewcontroller. I want to open sidemenu in all my viewcontroller in my project. But right now I am able to open it from my 'HomeViewcontroller' and only for one time.
In my AppDelegete.swift file I make function and it called in otpviewcontroller.
func createSideMenu(){
let storyBoard = UIStoryboard.init(name: "Main", bundle: nil)
let rootviewcontroller = storyBoard.instantiateViewController(withIdentifier: "HomeVC") as! HomeVC
let navigation = UINavigationController.init(rootViewController: rootviewcontroller)
let sideMenuVC = storyBoard.instantiateViewController(withIdentifier: "SideMenuVC") as! SideMenuVC
let sideMenuController = LGSideMenuController(rootViewController: navigation,
leftViewController: sideMenuVC,
rightViewController: nil)
sideMenuController.leftViewWidth = 280.0
sideMenuController.leftViewPresentationStyle = .scaleFromBig
self.window?.rootViewController = sideMenuController
self.window?.makeKeyAndVisible()
}
In my 'Homeviewcontroller' and otherviewcontroller I open sidemenu like this.
#IBAction func sideMenuAction(_ sender: UIBarButtonItem) {
self.sideMenuController?.showLeftView(animated: true, completionHandler: nil)
}
It open in only HomeViewcontroller but I want to open it in all Viewcontroller of my project. I am new in swift. Please help me. Thank you.
You can use the same method to open "LGSideMenuController" as you did in "HomeViewcontroller".
Suppose in another viewcontroller, you want to open "LGSideMenuController" on click of button event then code will look like
#IBAction func openSideMenu(_ sender: Any) {
self.sideMenuController?.showLeftView(animated: true, completionHandler: nil)
}
Edit Answer
I checked your code and found that you are trying to present another viewcontroller screen over "LGSideMenuController" instead of using push transition.
Please change your code in SideMenuVC controller as below
#IBAction func eventsAction(_ sender: Any) {
let vc = self.storyboard?.instantiateViewController(withIdentifier: "EventsVC") as! EventsVC
//let navigationController = UINavigationController(rootViewController: vc)
//self.present(navigationController, animated: true, completion: nil)
self.sideMenuController?.hideLeftViewAnimated()
self.sideMenuController?.rootViewController?.show(vc, sender: self)
}
In the above code, i hide the sidemenu first and then push "EventsVC" view controller in sideMenuController. Please apply the same code on other button actions.
Hope it helps.
I am trying to present VC2 from VC1 without using segue. It works. Then, I tried to use self.navigationController?.popViewControllerAnimated(true) to back but it does not work. I am wondering what is the code I should use to back from VC2 to VC1. Below code is in appDelegate.
AppDelegate
let storyboard = UIStoryboard(name: "Main", bundle: nil)
let VC2 = storyboard.instantiateViewControllerWithIdentifier("VC2") as! VC2
let navController = UINavigationController(rootViewController: VC2)
self.topViewController()!.presentViewController(navController, animated: false, completion: nil)
func topViewController(base: UIViewController? = UIApplication.sharedApplication().keyWindow?.rootViewController) -> UIViewController? {
if let MMDrawers = base as? MMDrawerController {
for MMDrawer in MMDrawers.childViewControllers {
return topViewController(MMDrawer)
}
}
if let nav = base as? UINavigationController {
return topViewController(nav.visibleViewController)
}
if let tab = base as? UITabBarController {
if let selected = tab.selectedViewController {
return topViewController(selected)
}
}
if let presented = base?.presentedViewController {
return topViewController(presented)
}
return base
}
VC2
#IBAction func backButtonTapped(sender: AnyObject) {
print(self.navigationController?.viewControllers) // print([<MyAppName.VC2: 0x12f147200>])
self.navigationController?.popViewControllerAnimated(true)
}
Here is the Flow of your navigation :
Current Screen - Presenting A New Screen (Which itself embed within a navigation controller with vc2) so Popviewcontroller won't work .
If you present any viewcontroller then popviewcontroller wont work rather use dismissviewcontroller to come out previous screen .
Use This :
self.dismissViewControllerAnimated(true, completion: {})
Solved!
Thanks.
I currently instantiate the storyboards programmatically like so:
var iphone35StoryBoard:UIStoryboard = UIStoryboard(name: "iphone35", bundle: nil)
var initialViewController:UIViewController = iphone35StoryBoard.instantiateInitialViewController() as! UIViewController
self.window = UIWindow(frame: UIScreen.mainScreen().bounds)
self.window?.rootViewController = initialViewController
self.window?.makeKeyAndVisible()
This is my first time working with push notifications, so I'm unsure as the best practice, but what i'm trying to do is in didReceiveRemoteNotification and while the app is in an active state(foreground), I would like to be able to determine what view the user is currently on to determine if i should A) Call a local notificaiton or B) update the view if the push notification corresponds to the visible view.
Using various other SO related questions, I have tried to access the visibleviewcontroller using these variations of code:
let navigationController = application.windows[0].rootViewController as! UINavigationController
1)
let visibleController: AnyObject? = navigationController.visibleViewController
if visibleController is ProfileViewController {
println("this works")
}
and
2)
let viewControllers: [UIViewController] = navigationController.viewControllers as! [UIViewController]
for vc in viewControllers {
if vc is ProfileViewController {
println("this works")
}
}
3)
if let wd = self.window {
var vc = wd.rootViewController
if(vc is UINavigationController){
vc = (vc as UINavigationController).visibleViewController
}
if(vc is ProfileViewController){
println("this works")
}
}
the problem i'm running into is that I can only obtain the rootviewcontroller and never the visible view controller. The rootviewcontroller in this case is a login screen, and despite me being on the profileViewController, i can only obtain the loginviewcontroller. Is this the best method for dealing with push notifications?
Move to destination view controller from storyboard when push notification will came
let mainStoryboard: UIStoryboard = UIStoryboard(name: "Main",bundle: nil)
var destViewController : destVC
destViewController = mainStoryboard.instantiateViewControllerWithIdentifier("destVC") as! destVC
var navigationController = UIApplication.sharedApplication().keyWindow!.rootViewController as! UINavigationController
navigationController.pushViewController(destViewController, animated: true)
This is working for me from appdelegate.
Use notification center for more stuff :
NSNotificationCenter.defaultCenter().postNotificationName("name", object: nil, userInfo:nil)
NSNotificationCenter.defaultCenter().addObserver(self, selector: "method:", name: "name", object: nil)
func method(notification: NSNotification) {
//Do your stuff.
}
Passing data with notification center
NSNotificationCenter.defaultCenter().postNotificationName("name", object:nil, userInfo:["message":"Unable to add \(homeName) Home"])
func method(notification: NSNotification) {
//Do your stuff.
println(notification.userInfo)
}