I created a simple Show segue by dragging from a UIButton to another UIViewController in storyboard view. It's configured as all of my other VCs and has a custom class that is specified, with linked IBOutlets and IBActions (which appear to link up when I hover on them).
NOTE: When I first created it, there was no view controller class specified. I've recreated it several times since then, but I'm wondering if some value is cached that's pointing to a default view controller. Although I get print lines from the correct view did load method...
For some reason, when I run the app and click the button it links to a black, empty view controller. The navbar pops up without any back button (these views are embedded in UINavigationController).
After looking up other posts about this kind of issue, I've deleted and recreated the segue, cleaned my build folder and restarted Xcode. There's no source code involved in this, just storyboard configuration. Any help on next steps?
According to the code shown in your screen shot, the problem would be that NodeEnrollmentViewController is a subclass of UINavigationController. That's wrong. It should be a subclass of UIViewController.
You cannot (and do not need to) segue from a view controller within a navigation controller to a navigation controller.
Related
I have an app that represents a folder structure. I have a UITableViewController for the folders and files listing, and a UIViewController for the Documents.
I want to be able to recursively navigate through the folder structure, so I want to reuse the Folder UITableView multiple times while I let the user drill down a folder structure.
Is there a way to draw a segue from the UITableViewController to self so when I select a folder I present another instance of the view, but with the content of the subfolder?
I did this in previous versions of Xcode, but I cannot figure this out on Xcode 9.
You can use Storyboard Reference and Storyboard ID of ViewController in Interface Builder
Screenshot
Yes you can do it. Add a hidden button in view controller and drag & drop segue self view controller.
I've never created a segue link to the same view controller, but based on Halil's answer above, it sounds like it's possible.
Rather than messing with hidden buttons, though, why don't you give your scene a storyboard identifier, and then instantiate and push/present your view controller through code? You could put your logic in the table view's tableView(_:didSelectRowAt:) method.
I made an app with two View Controllers and storyboard to them. At all everything works perfectly but at all I must to create framework from this objects.
The structure looks like this:
Framework:
FirstViewController.swift
SecondViewController.swift
Storyboard.storyboard
AppExample:
AppDelegate.swift
I want to present in AppDelegate first View Controller. After presented it user will make some stuff and after push the button SecondViewController will be pushed on the screen. This second View Controller could be dismiss by the user.
The problem is:
I move all swift files to the Framework folder with right target membership.
After init the First ViewController I have blank screen
I do not know how to connect storyboard with the views
This two UIView Controllers are only the tool that will be added to the few apps later. The point is that developer can put first View Controller wherever he want and after that he will have the answer from Second View Controller.
I will be glad for help.
I need to navigate inside folders and files in directory (from server). The problem is that I don't know the number of folders so it's not possible to use performSegueWithIdentifier statically. How can I use navigation controller with dynamically number of view controllers in swift? I want to "push" a new view controller every time a user tap on a folder in order to list files/folders inside it and I want to do it with UINavigationController so the user have the possibility to go back with "previous" button.
Both storyboard and programmatically approaches are ok.
Thanks you
Storyboards and segues are just a crutch. Think about how you would do this without them. At each level, to go down a level, you would just instantiate a new view controller and push it onto the navigation controller stack with pushViewController:animated:.
https://developer.apple.com/library/ios/documentation/UIKit/Reference/UINavigationController_Class/#//apple_ref/occ/instm/UINavigationController/pushViewController:animated:
And in fact it takes only one view controller class to do this, since any instance can create and push another instance of its own class. The display of one folder is exactly like the display of any other.
So if you wanted to configure this notion in a storyboard, you would have a circular segue, that is, the view controller would have a push / show segue leading to itself.
I agree with #matt's answer, just create the controller and push it. For sake of completeness, you can do this in a Storyboard with a segue.
Here's how:
So that you can call the segue programmatically, add an additional prototype cell to your tableView. (You do this because you don't want the segue to be automatically triggered when the tableViewCell is selected. By using an additional prototype cell, the segue can be wired up, but it will never be triggered automatically since this prototype cell will never actually be instantiated.)
Control-drag from this prototype cell to the viewController icon at the top of the tableViewController. Select "Show" from the pop-up.
Find this segue in the Document Outline View and give it an identifier such as "showFolderSegue" in the Attributes Inspector.
Now, when you want to trigger the segue, call: self.performSegueWithIdentifier("showFolderSegue", sender: self)
You can use prepareForSegue to set up the new tableViewController as you normally would.
This method too works with a single tableViewController.
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.
Is it possible to create a storyboard segue from a view controller to itself? I have a bunch of Entities that have Related Entities. I'd like to be able to display a Related Entity using the same view controller that's displaying the Entity. But I can't seem to create a segue that will display a new instance of the origin view controller.
Is it just not allowed? Thanks!
Well here's a solution that isn't quite the same but gets me what I want. I found it as an answer to this question.
The reason I thought I had to use a segue rather than the good old programmatic push of a view controller onto the navigation controller's stack is that I had set up the view controller's IBOutlets in the storyboard. I didn't realize that you could create a copy of the view controller as laid out in the storyboard without using a storyboard segue. You can! To see how to do it, check out that other question and up vote the answerer!
You can ctrl-click-drag (or right-click-drag) from an element (UIButton, etc.) to the containing view controller.
(Did you try this? I'm doing it right now; I have one stock UIViewController that just keeps adding itself indefinitely to the containing UINavigationController stack via a normal push segue.)
Yeah, it's annoying I can't do a 'manual' segue to itself.
What I did was added a UIButton to my view and gave it an action of push to the same view controller, and then made this button hidden. Then I can name the segue and reference it in the code.
Hacky, but works.