i have one question about using multiple segues to one ViewController. Ill try to create an article management, so you can add/edit/delete articles.
When you add a new article you can choose between a maincategory and a subcategory, choose the article and then edit some inital values.
but if ill try to edit one of my selected articles, i would like to jump to the "latest" ViewController in navigation stack.
I thought i could easily create another segue to my last viewController, but ill always get an error when i try to load this segue (i guess this could be a problem with the existing NavigationController).
I could provide some code, but i dont know if this is a possible solution to solve such things - or is there a better way?
Thanks in advance.
You can, but the new segue should take you to a navigation controller that just contains the last view controller (as the root). In this way you are duplicating the normal situation but with only 1 view controller.
If you wanted to allow the last view controller to have a 'back' button which took you to some 'earlier' screens (if that makes any kind of sense in your app) then you would need to write some code. It's more likely that other screens should be accessed via bar button items or similar (which would also likely be done in code).
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Trying to follow some best practices so looking for suggestions.
Have 2 types of users: user, admin
And want to present a different “version” of a particular view controller to certain user types. This particular view controller is nested into a tab bar controller, and the other view controllers in the tab bar controller will be the same for each user.
Possibly overthinking this, and thought about going the the route of hiding storyboard elements based on user type, but there must be a better way to accomplish presenting different versions of a view controller nested in a tab bar controller.
You can simply create two different ViewControllers and segue to the correct one based on the user type.
If you start at InitialViewController, then create two different segues that go to AdminViewController and UserViewController. Afterwards, perform the type-checking in InitialViewController and segue accordingly to the correct one.
There are a lot of other ways to overcome your problem. If you need any further clarification or a different way of doing so, do not hesitate commenting!
The app I am currently working on requires that I do not use ANY storyboards. Therefore I need to do everything programmatically. One thing I seem to be struggling with is switching between two UIViewControllers.
The issue is that every time I call the self.present() method; it creates a brand new instance of the class I would like to show. So when I go into Xcode's visual debugger, I see over 15 different views that are all stacked and are merely instantiations of one another. Ex: View1, View2, View1, View2, View1, View2, View1... This constant repetition of the views is significantly hurting the performance of my app. So my question:
Is there a way that I can switch between my two UIViewControllers without constantly creating a new instance of each one?
Again, I am doing all of this with ALL storyboards DELETED. So the solution I necessary needs to be implemented using ONLY code.
I think you should create main ViewController.
if you keep your two instance view controller, create two controller in mainViewController. Then keep that in main viewController.
And push view controller you want to present in navigation of main view controller
if you want to change second view controller pop navigation controller and push another, or just push other controller.
if you want keep your instance view controller i think it's best option for you
I think that it is really important to realize the fact that the view controller will show up multiple times in the debugger because that is something that can throw off the performance of the app. I really like the way you mention that in your comment. This is one of the main differences that can outstand you from another programmer in the same field. One of the most easiest and simple ways to fix this problem would be using the self.dismiss() method. Another way to dismiss this view controller would be to use a navigation controller to fix this problem. A navigation controller will push the main view controller out of the way and it will not create multiple instances of it. This will be the most efficient as it doesn't require a lot of code and a mere initialization of the UINavigationController class implemented in the UIKit. This is one of the most important tools and resources that you must make use of while coding in xcode and developing your skills in the swift ios field. Since this problem is not one of the most common to find on the internet, it is very beneficial for you to post it on this forum page and will really be helpful for some other programmers unaware of such methods and ways to code. One of the questions that I have for you is the fact that you don't want to use storyboards. Why don't you want to use storyboards and only make it proGrAMitcally? This is one of the very questions that manages to astound me. The storyboard is an implementation that makes it very easy for xcode and swift users to work around the tedious work that has to be done while working in the coding aspect. It only takes a few lines of code and you can get a seGu done very easily. The switch is very easily done and you can find this method on some youtube channels. For this type of work, I recommend VigneshSriniswami Patel and ShaniLakshmiVishnuJiSwami, these content creators will help guide you to becoming an xcode master.
Hope I helped!
I swear I tried to find an answer to this question but can't seem to lick this issue.
I have a table view that I would like to take the user to 4 different viewcontrollers as each destination viewcontroller from the menu needs very different functionality/layout. However, at present I can only go to one view controller. If I simply put in buttons instead of the table view I can accomplish this but this doesn't seem like best practice and I enjoy some of the clean/tightness of the table view. Also, I do not need to pass anything from the parent viewcontroller.
I'm new, if my newb question wasn't obvious enough. If there is a tutorial/page/resource you can point me to that'd be greatly appreciated by myself and the non-profit I'm trying to do this for :)
Thanks for your time and consideration!
I figured it out. In case someone else has this problem and has stumbled onto my question before seeing it answered elsewhere. A newb like myself didn't know enough about segues. You'll need background on creating segues in storyboard from the parent view controller to the children with unique segue IDs and then take care of the rest in the .m file of the parent. Also be careful about assigning the delegate of your table view as this was another silly oversight of mine.
Here's the link I found most helpful.
Can I use multiple segues with one UITableViewDelegate?
I'm very new to iOS but have been put on a complex app. All the tutorials I have seen on storyboards, segues, views, etc. are very simple.
I have been able to use a segue to show a view and go back, but management doesn't care about segues. After moving through a complex app the user is supposed to be able to just jump way over to another part of the app, as if the user had gone back twice then selected another view, and then selected another view.
I'm just lost as to how to make this happen. Add a new direct segue in the storyboard editor? Or something to do with a custom segue created programatically? I need some hints on direction, like what methods to look at, what to google or a advanced tutorial and such. Thanks in advance.
Usually, the Navigation Controller allows single 'pop's of view controllers in the stack. This works great for master-detail apps and linear workflows.
When one view controller is connected to another in a web-like fashion, things get difficult to manage.
If you want to rely on the automatted management of a view controller stack but go back more than one item at once, have a look at unwind segues: What are Unwind segues for and how do you use them? -- the answer is illustrated really well.
If you can navigate in circles, it gets more intricate. Essentially, your navigation controller would put new objects of already intantiated classes onto the stack to maintain its breadcrumb trail all the way back to the root view controller.
In some cases, this is not desirable. You could use a UINavigationControllerDelegate which removes items from the stack when certain conditions are met.
Let's say you have 4 view controllers, A--D. The possible connections are: A - B - C - {B,D} - A. From D, when you're finished, you want to unwind to A. From C, you may want to add an additional item at B, but you don't want to keep track of all the B-C-B-C-B-C-... connections. In these cases, altering the navigation controller history is useful and won't break the expected behavior of the "back" button.
Situation: two UITabBarController's, each with their own tabs, but last tab in both is identical so want one UIViewController to show content.
Issue at runtime: Shared item only appears in one of the tab sets when shown.
Question: anyone know a way to make this work?
Link to external graphic of storyboard setup: (sorry, don't have enough reputation to post images here!)
Storyboard graphic
An Xcode project with that storyboard:
XCode Project
Each tab content item has it's own UIViewController class. They contain no code except the line to make the back buttons work.
(Yes, I know this is odd. Real situation is an iPad app where tab controllers are shown in popovers; popovers are "property editors" where different objects have different properties, but all share a common set of properties... thus one tab for "unique" props, one shared tab content for the "common" props all objects have.)
I've found a couple ways around this to get the effect I want, but if this storyboard worked it would be a much easier solution.
-- Other info, somewhat unrelated to question --
Alternate solution I'm using: TabBarControllers only link to one VC as tab content. When that tab VC loads, I use code to (a) instantiate shared VC from storyboard by identifier, (b) add that new VC object to the TabBarController via [tabController setViewControllers:list animated:NO].
(Another possible solution I like even less: not using a TabBarController, and presenting content VC's with my own "tab" graphic drawn into them, each showing "myself" as selected. Yuk.)
So I have a working solution, I'm just curious as to why this doesn't work (just a known thing in iOS API, or some magical property setting that might render it functional?)
You can't put the same view controller instance into two tab controllers. The problem is that a view (UIView) instance can only have one parent view (superview). When you try to add the view controller to the 2nd tab, the view controller's view gets removed from its first parent (the first tab) and then added to the 2nd tab.
I stumbled upon your thread while running into the same issue today...
The solution is to just make a duplicate of the view controller in story board and attach the duplicate to the other tab bar controller.
I just did it and it works...
I think the 'rdelmar' is right about this... copy it and set it ..!!
I ran across this same issue today. I managed to come up with a workaround that seems to do the trick. The key is to add a layer of separation between the tabbar and the controller you want to reuse. From each tabbar, I created a relationship to a distinct UIViewController with a container view. Then you can do an 'embed' segue from the container to the controller you actually want to reuse as the tab view. It is not quite as clean as a direct connection (not sure why that is not supported) since you do have to create a controller class for each reuse case. It is still a better solution than the nightmare of having to duplicate the actual tab view ( as well as any additional views that connect to it) for every use.
Hope this helps. Let me know if anyone needs more details.