I have a SKScene that acts as somewhat of a main menu. And I use container views that have various view controllers such as settings etc...
The problem is, players can still tap on nodes etc behind the view controller in the container view. Is there a way to prevent this?
Had help from a friend who wrote an extension that solved this, presented the view over the top:
extension UIViewController {
var topPresentedViewController: UIViewController {
if let vc = self.presentedViewController {
return vc.topPresentedViewController
}
return self
}
}
Related
I'm building an app with three views and I want the user to be able to swipe between them but also navigate between them by using custom buttons, like browsing in safari but only with three available views. The user can navigate between them in a somewhat random order and I provide back and forward buttons in a toolbar.
After reading Apple's documentation I believe history mode is the option I'm looking for as I can provide the views separately and navigation is not predefined like in book mode, however when I implement it it adds my view to the arrangedObjects property but the view itself doesn't change. I've correctly wired the page controller view programmatically to a subview of the app's contentView and I can see said view correctly displayed while debugging the view hierarchy.
The "Page Controller Managed View" is set as NSPageController.view programatically.
When I try using navigateForward(to:) the view gets added correctly to the arrangedObjects and the selectedIndex is correctly set but the NSPageController.view doesn't change at all (remains a blank NSView like the loaded view from storyboard). This is my code:
class MainViewController: NSViewController {
// MARK - Instance Properties
var notificationObservers: Array<NSObjectProtocol> = []
var pageController: NSPageController?
// MARK - Interface Builder Outlets
#IBOutlet var mainContentView: NSView? // Named "Page Controller Managed View" in storyboard
override func viewDidLoad() {
super.viewDidLoad()
pageController = (NSStoryboard.main!.instantiateController(
withIdentifier: "MainPageController") as! NSPageController)
pageController!.delegate = AppDelegate
pageController!.view = mainContentView!
notificationObservers.append(
NotificationCenter.default.addObserver(
forName: NSApplication.didFinishLaunchingNotification,
object: NSApp,
queue: .main,
using: { [weak self] (notification) in
// If the 'arrangedObjects' property is 0 it means no other object has set the first view
if self?.pageController!.arrangedObjects.count == 0 {
// Set the first view
self.pageController!.navigateForward(to: AppDelegate.firstView.nsView)
}
})
)
}
deinit {
// Perform cleanup of any Apple Notification Center notifications to which we may have registered
notificationObservers.forEach { (observer) in
NotificationCenter.default.removeObserver(observer)
}
}
}
This is the view hierarchy while running the app:
What am I doing wrong? Why is the page controller view not being updated with the navigateForward(to:) view?
This could shorten the amount of code I have to use by a lot compared to using view controllers (Book mode) so any help is appreciated.
I'm trying to implement an IOS swift app which starts off with a tab bar controller, and in one of the tab bar controllers is an item called "account".
When a user presses the account item, I want the app to decide (onclick event) whether the view that contains sign up/login is displayed or the profile view is displayed based on a global variable "loggedIn" (bool type).
(I've tried navigation controller but what I've understood from that is that it is a sequence of views which can't decide between views)
I want to know how can this be implemented, maybe some kind of "router" if you may that can switch between views...
If you didn't understand here's a picture of what I'm trying to implement
Basic Map of what I'm trying to explain
If you can suggest a more professional way of doing such design please don't hesitate to express your opinion.
I believe a good approach is updating the view controller when loggedIn status changes. If you don't already have, create a class inheriting from UITabBarController to manage your tabs. Here's the code:
class TabController: UITabBarController {}
In your storyboard, select your tab controller, go to the Identity Inspector and set TabController as the custom class. Now TabController will manage all the view controllers in your tab bar.
It's usually not a good approach to use global variables, so let's add loggedIn in the scope of TabController and listen for any of changes in it and update the corresponding view controller:
class TabController: UITabBarController {
var loggedIn = true {
didSet {
updateProfileTab()
}
}
}
Now, whenever you change loggedIn, that change will update the proper tab. Now let's write updateProfileTab():
class TabController: UITabBarController {
func updateProfileTab() {
let viewController: UIViewController
if loggedIn {
viewController = makeProfileViewController()
} else {
viewController = makeLoginViewController()
}
setViewController(viewController, at: 2)
}
func makeProfileViewController() -> ProfileViewController {
// create and return the profile view controller
}
func makeLoginViewController() -> LoginViewController {
// create and return the profile view controller
}
}
Naturally, you might want to write the body of both makeProfileViewController and makeLoginViewController methods. The last thing for TabController is to write setViewController(_:at:) method:
class TabController: UITabBarController {
...
func setViewController(_ viewController: UIViewController, at index: Int) {
let tabBarItem = viewControllers?[index].tabBarItem
viewController.tabBarItem = tabBarItem
viewControllers?[index] = viewController
}
...
}
Now, since TabController manages your tab bar, you can access it from within any of its children view controllers:
guard let tabController = tabBarController as? TabController else { return }
tabController.loggedIn = ...
Also, it's important to select the initial state. So, in the viewDidLoad from one of your tabbed view controllers, you should perform the above code. The first tab (the one that displays first) is probably the best place to do that. Hope this helps!
EDIT
To create your login and signup view controllers, the easiest way to go is by assigning ids in your storyboard. To do that, go to your storyboard, select the view controller, and in the Identity Inspector set a Storyboard ID, which you will use to instantiate the view controller:
func makeProfileViewController() -> ProfileViewController {
let controller = self.storyboard!.instantiateViewController(withIdentifier: "theStoryboardID")
return controller as! ProfileViewController
}
Note that I'm using force unwrap here (!). That's just for brevity. In a real case scenario you will want to use some if let or guard let statements to handle nil values.
The main ViewController is embedded in a UINavigationController subclass, and the VC has a subview that is loaded from a nib. The subview is called MenuView, and contains UIButtons that will link to other VCs.
To keep my main ViewController less unruly, I have put all these buttons into a subview that loads from a nib that animates the menu opening and closing.
However, I would like to present other view controllers from these, sometimes "Modally", sometimes "Show". What I have done seems to work, but I just want to know if this is alright, or if I have caused some unwanted effects that I'm unaware of (like a strong reference cycle that would cause a memory leak, or something). Or is there a better way to do this?
Some code:
In MenuView.swift
class MenuView: UIView {
var navigationController = CustomNavigationController()
func combinedInit(){
NSBundle.mainBundle().loadNibNamed("MenuViewXib", owner: self, options: nil)
addSubview(mainView)
mainView.frame = self.bounds
}
#IBAction func optionsAction(sender: AnyObject) {
self.navigationController.performSegueWithIdentifier("presentOptions", sender: self)
}
In ViewController.swift
menuView.navigationController = self.navigationController as! CustomNavigationController
Short answer: No, it is not alright to access a view controller from within some view in the hierarchy, because that would break all the MVC rules written.
UIView objects are meant to display UI components in the screen and are responsible for drawing and laying out their child views correctly. That's all there is. Nothing more, nothing less.
You should handle those kind of interactions between views and controllers always in the controller in which the view in question actually belong. If you need to send messages from a view to its view controller, you can make use of either the delegate approach or NSNotificationCenter class.
If I were in your shoes, I would use a delegate when view needs some information from its view controller. It is more understandable than using notification center as it makes it much easier to keep track of what's going on between. If the view controller needs some information from a view (in other words, the other way around), I'd go with the notification center.
protocol MenuViewDelegate: class {
func menuViewDidClick(menuView: MenuView)
}
class MenuView: UIView {
var weak delegate: MenuViewDelegate?
#IBAction func optionsAction(sender: AnyObject) {
delegate?.menuViewDidClick(self)
}
}
Let's look at what's going on at the view controller side:
class MenuViewController: UIViewController, MenuViewDelegate {
override func viewDidLoad() {
...
self.menuView.delegate = self
}
func menuViewDidClick(menuView: MenuView) {
navigationController?.performSegueWithIdentifier("presentOptions", sender: self)
}
}
For more information about communication patterns in iOS, you might want to take a look at this great article in order to comprehend how they work.
I have a document window that contains a number of NSView subclasses, switched between using a tab control. Each of the subclasses, and the window's ViewController, support different user actions accessed through menu items tied to the First Responder.
I'd like to perform a segue from one of those views in response to a menu item. However, NSView does not support performSegueWithIdentifier, it appears to be something that is part of NSViewController alone.
Can someone suggest a way around this? I have seen suggestions to pass the VC into the views, but I am not clear how to do that. Or perhaps there is a better way?
view.containingController.performSegue()
note: you have to add containingController to your views
I WOULD add the viewController to the responder chain and then make containingController a computed property in an extension!
e.g. add vc as responder:
override func awakeFromNib() {
super.awakeFromNib()
self.nextResponder = self.view
for subview in self.view.subviews {
subview.nextResponder = self
}
}
e.g. containingController in extension
extension NSView {
var containingController: NSViewController? {
get {
while(self.nextResponder != nil) {
if(self.nextResponder is NSViewController) {
return self.nextResponder
}
}
return nil
}
}
}
You could do that (see Daij-Djan's answer), however it is not what I would recommend, since a hypothetical programmer who will be using your code, but is not familiar with it (let's say, you in a year :) ) might be caught by surprise by such behaviour.
I would recommend you to add a delegate (conforming to your custom protocol, let's call it MyViewDelegate) to your NSView with a method like viewRequiresToPerformTransition(view: YourViewSubclass). Then you implement this method (more generally, you conform to MyViewDelegate protocol) in your view controller and inside its implementation perform any segue you want.
I am so stuck right now, I have tried everything which seams logical to me to make this work but having no luck...
I got this in a separate swift file:
import Foundation
import UIKit
class MyViewController: UIViewController {
func background() {
var imageView : UIImageView
imageView = UIImageView(frame:CGRectMake(0, 0, 100, 300));
imageView.image = UIImage(named:"bg.jpg")
self.view.addSubview(imageView)
}
}
I want to call it into a separate view controller file. The reason I am doing it like this is because then I can just call the background class in all my view controllers a and I don't have to do the same code in each one.
The ways I have tried calling it are:
MyViewController.background() - I get error Missing parameter for #1 in call
background() - I get error Use of unresolved identifier 'background'
MyViewController() - I don't get error but nothing happens.
I would really appreciate it if someone could tell me how I can call this function into my 'ViewDidLoad' part in the view controller.
Thank you.
You're barking up the wrong tree. Even if you could call the background method in MyViewController, this would still not accomplish what you are trying to accomplish, because when you call background in the "separate view controller file", the self in the background method would be the other view controller - and so you would be putting the UIImageView into the other view controller's view, not this view controller's view. If you want to be able to do the same thing separately in each view controller, you need to make the background method available internally in each of them.
The way to do that is to inject background through an extension into UIViewController itself, from which all your view controllers inherit:
extension UIViewController {
func background() {
var imageView = UIImageView(frame:CGRectMake(0, 0, 100, 300))
imageView.image = UIImage(named:"bg.jpg")
self.view.addSubview(imageView)
}
}
Now any view controller in your app can just say self.background() (or simply background()) to call this method.