How to model different initial screen on app launch depending upon state with storyboards? - ios

Whenever my app launches one of 3 possible screens will be displayed depending upon the state.
I was going to model this in a storyboard by having the starting view controller as a navigation view controller, then have a segue from it to each of the three other VCs.
Then on app launch the appropriate VC would get pushed depending upon the app's stored state.
However IB will not permit me to make multiple connections from the navigation controller.
If I make an initial segue from the NVC to any of the VCs, say A. Then when I attempt to add another segue from the NVC to another of the VC, B, then instead IB creates a connection between A and B.
First of all is the approach of having a Navigation Controller as a starting RVC and pushing different VCs onto depending on state an incorrect approach? If not, then how to model it with storyboards? Why will IB not let me drag and drop the segue to the other controller?

I don't think the navigation controller is the way to go. IB won't let you connect more than one, because that first connection is the root view controller, and there is only one of those.
There a many different ways you could get what you want depending on where you go after one of those 3 initial views. Do they all go to the same view next? All different view? Some the same, some different? It's hard to advise you without more detail.
You could start off with a tab bar controller, with the tab bar hidden, if you don't want that look. Or, you could have logic in the viewDidAppear method of a common initial controller, and have it switch the root view controller of the window to on of your three screens.

Related

Launching to a level other than root in UINavigationController, from a storyboard

Is it possible to launch an app to a specific level of a navigation stack using a storyboard?
I'm looking to recreate the model employed by Mail.app, where the app launches into the Inbox, but this is actually one level down the navigation stack, and tapping the back button takes you to the root...
I understand how this can be done via code, i.e. instantiating the navigation controller within the app delegate and then manually pushing the view controller(s) to create the desired stack, but I'd really like to know if there's a way to achieve the same using storyboards.
Unfortunately I don't think there is because you need to instantiate your navigation controller at some point that will house your view controllers, and if you do this through storyboards the best you can do is set the navigation controller to be the entry point.
However, it is pretty straightforward to do from code. If your navigation controller has two view controllers where ViewControllerOne pushes to ViewControllerTwo, then you can just can just push to the second one without an animation as follows:
navigationController.pushViewController(secondViewController, animated: false)
And the user will be one level deep in the navigation controller.

I need some clarity on Navigation Controllers

I have a total of 3 views. A menu, the main view where the action happens, and a settings menu.
You can access the settings from both the menu and the main view and go back using the back button provided by the Navigation Controller.
In the main view I have hidden the NavigationBar to free some space, and there's a specific button to go back to the menu. From what I know and have read, I assume this just adds more and more views to the Navigation Stack if I keep going from the main view to the menu again and again, creating a lot of views in the stack.
I'd like someone to tell me whether my assumption is true or not, and evt. explain me the whole process behind navigating and views.
UINavigationController has a property viewControllers which is the stack of view controllers that have been pushed there.
If you use push segues in your storyboard each time you trigger this segues you push the current controller to the stack.
If you have a special logic I suggest you manage controllers programmatically.
This might clear it all.
There are basically following types of Segues to navigate to any viewController
Show (Push)
Show Detail (Replace)
Present Modally
Present as Popover
And to move back use Unwind Segue
You can read more regarding this here

Benefits from using UiNavigationController

I am developing an iOS app that I have already developed for Android.
The problem is I don't know how to organize my UIViewControllers considering the following scheme of my app pages:
The scheme is simple: there is a login page which leads to the main page. From this main page, there are four buttons which all lead to a specific view hierarchy but at the very bottom of each, the user will be able to go back directly to the main page. Each page accessed by the main page will also have a custom back button (an image of my own)
The question is: is there any benefit in using a UINavigationController (obviously with the main page as its root) in my case? Or can I simply create each Controller and using only Modal Segues?
If your view controllers have a navigation relationship so using UINavigationController is the way to go:
In 'push' segue, you are basically pushing your ViewController into an
already setup "navigation stack". Well, of course, this is under the
assumption that the ViewController that performs the 'pushing'
operation belongs to the same navigation stack as the ViewController
is pushed into. Generally, you push a ViewController if the pushed
ViewController has some sort of a relationship with the pushing
ViewController. This is very common in applications that has a
NavigationController in its system. A good example for a push segue is
a system where you are displaying a list of contacts. And on tap of a
particular contact, you are pushing a VC that has the corresponding
details of the contact.
Example is real world: list of products => product details => product reviews
If you want to temporary present a view controller and the main focus is your view controller but you need to present another view controller to perform a task like "filter" , "login", adjust "settings" then modal segue is the way to go
In 'modal' segue, there is no stack as such. You are presenting a VC
'modally' over the presentee VC, if that makes sense. This can happen
across any ViewController without any relationship rules. The
presenter should take care of dismissing the VC it presented. A good
example for modal segue is login. On tap of login, you are modally
presenting a VC that has no relationship with the presenter.
If your view controllers are not related to each other, but each view controller has his own navigation stack then UITabBarController is the way to go
Storyboards (Xcode): What is the difference between a push and modal segue?
I would say if each of the additional view controllers from the main "home" view controller don't have any children view controllers, then you can just have each button present a view controller modally.
The main difference is if you are using a navigation controller, you can "pushing" a vc onto the navigation stack of view controllers, whereas presenting it modally can be thought of a "one time" action where the user does something on the new screen and has no where to advance to logically (like adding information to a new contact).
You can see this post for a more detailed answer:
What is the difference between Modal and Push segue in Storyboards?
Deciding whether to use a Modal segue vs a Show (push) depends entirely on purpose and context of the user's experience. If you are leading the user down a path which is linear, where each successive VC is diving deeper in to a singular idea, then use Show segues and NavigationControllers. Examples include, Settings app, where you can drill into all the specifics. Most e-commerce app will use a NavigationController to lead the user through a purchase.
If you want to present the user with a single concept, which the user can respond to, or close it to continue using the rest of the app. Then use a modal presentation. Adding a contact in the iPhone is a fine example of this.
Visually, the difference is that a Show segue presents the VC from the right side of the app, sliding onto the previous VC. (If the user has Arabic language turned on, a right to left language, the Show segue will come from the left hand side of the VC) A modal comes from the bottom of the app.
From looking at your drawing, but not know anything else about your app, I think you want to use NavigationControllers. You may also want to consider a TabBarController. If each of these buttons lead the user on various ways of using the app, like mini apps within one big one, then a TabBarController is appropriate.

Use of differenct view controllers

i'm curious about what's the best way to plan the controllers for my app.
i want my main screen to have 3 button.
1) should open a nav controller with details view
2) should open a controller with other buttons that lead to others controllers
3) should open a tab bar with 2 pages ( or eventually use a switch to change page instead of the tab bar)
this is the schema of what i want
http://i59.tinypic.com/2rrvrd4.png
Is it a correct schema or i should use my controllers differently? will apple reject an apple with such schema?
thanks
As #Fogmeister pointed out in the comments, going for a UITabBarController as the main interface for your app actually seems to be a more appropriate solution here.
However, you can go with the interface that you described, but then you should keep in mind that with your current setup, you are not only using UINavigationController in the first case, but your whole navigation system is still built upon UINavigationController in the following way:
Your app has one instance of UINavigationController.
Your initial UIViewController (the one with the three buttons), is the rootViewController of your UINavigationController.
You can navigate to the other view controllers using [self.navigationController pushViewController:newViewController] (or performSegue if you prefer using Storyboards).
In the case of your third view controller, you are pushing a UITabBarController onto the navigation controller's view controller stack, this UITabBarController needs to be initialized with the two view controllers that it is going to display before it gets pushed onto the stack.

How to point two UINavigationControllers to one view controller using storyboards?

I am attempting to connect two UINavigationControllers, representing different tabs in a tab bar application, towards a single UICollectionViewController. The collection view controller will be populated by different data based on which navigation controller is the parent. When both navigation controllers are connected, navigating to the second tab displays a black screen and the viewWillAppear() code in the controller for the collection view does not fire. When navigating to the first tab, everything fires and is displayed correctly with data populated.
The storyboard setup looks like this:
The navigation controllers are connected to the collection view controller as seen here:
If I disconnect either one of the two navigation controller connections, the remaining connection to the collection view works and collection items are displayed as expected.
Is this the correct way to reuse the collection view? Is there something missing from how I am connecting the two navigation controllers with segues to the single UICollectionView?
I see this is almost a year old, so I'm not sure if you found an answer or not, but I thought I'd help answer if needed. Without knowing too much of your project, can I ask why you want a tabBarController to point both of its view controllers to the same one? Makes me wonder why tabBarController is necessary.
Setting up a test project, I witnessed the same you did. The only thing I can think of is that when a view controller is instantiated via the Storyboard, it creates an instance of it and is stored in the tabBarController's viewControllers[i] property, which the other tab may not have access to in the hierarchy. It would be best to just copy the view controller object from the Storyboard and paste it onto another area of the storyboard, and have the tabBarController instantiate a new instance of the same view controller object. That way, in your viewDidLoad method, you can tell what the selectedIndex is, and know how to load data, alter interface, etc. Copying/pasting the Storyboard view controller should keep intact any outlets/actions you've set up.
Hope that helps...

Resources