Could not cast value of type 'UIButton' to 'NSURL' - ios

I am working on a Udacity course for building iOS apps. I have come across this problem in the connection/segue between the two screens of the course app and can't seem to find answers on the Udacity forum. I've gone back and checked my steps so really don't know why its happening. It is shown in the attached screen capture.
The problem is baffling and I'd like to get through this before proceeding with the rest of the course.

when creating the segue you connected it from the button to the destination view controller, so it will crash because the sender is a UIButton. To fix this issue, first remove your segue. Then create a new one from the view controller to the destination view controller (with the same name you had previously).

Related

Whose View is not on hierarchy

I am getting this error from swift and I am unsure why there is only 1 view controller that actually has this occurring the error is whose view in not on the hierarchy. My question is why would this occur for one of the view controllers presented from this primary viewcontroller button but not the other view controller linked from this primaryview controller? Is there something that could cause this to occur specifically. I am trying to present this modally and it is being called programmatically so that I can pass data objects.
For me it just seems very strange that this would occur for one viewcontroller presented from this viewcontroller but not the other. The only thing I did which I didn't think would effect this was duplicating the primary viewcontroller but again why would one work but not the other? The problem is specifically happening with iOS.
Should have checked the buttons to make sure they were linked correctly. I realized after reading a few of the same questions that I should check the button selectors under the view controller references tab to see what was linked to what. I had 2 actions doing 2 different things for 1 button by accident I must have miss clicked the control drag function.

How to segue to View Controller from skview

As simple as this question may seem, I just couldn't figure it out. To the overflow community, I am using sprite kit to create a simple game, However when you lose the game I want to programmatically segue back to another viewController (basically the home screen). from The game scene I do not get access to "performSegueWithIdentifier" I've seen a couple answers that relate to this topic however non of them are in swift ... Any solutions?
links of related questions include : Link1
Thank You
I think you are misunderstanding SKViews. SKViews are just like a normal UIViews, they take place within a normal ViewController. You will therefore need to segue from the ViewController which is presenting your SKView.
I have the same issue in a game I have created (Ninja-Shooter). In my game, whenever I want to segue back the home screen I pass a value to NSUserDefaults.standardUserDefaults(). Then in my ViewController I am constantly listening for any change in that value, if the value does change, then I perform a segue.
Hope this helps!
I have discovered that using NSNotification Center Can in fact derive the results I was looking for. If any one in the future needs detailed code I will edit to provide that

Scene is unreachable (XCODE 5 iOS developer)

I am new to iOS developing and I hit an error saying "Scene is untraceable due to lack of entry points and does not have an identifier for runtime" I was wondering how to fix this problem? As I have no idea how too haha
You can fix this by giving your viewController a storyboard Id
Or you need to make sure it has a segue to another controller, in short a view controller must be reachable.
As meda answered, view controller must be reachable with a storyboard id either with a segue.
Before you give storyboard IDs to all of your views or make segue links to them, make sure you don't have any "duplicated" view stacking on the original view. pressing 'Cmd C and Cmd V' makes that happen.
so, drag around your views one by one to reveal duplicated views.
Double clicking that warning message helps you focus on the view causing the problem as well.

Two UITabBarControllers sharing one ViewController (as tab content)?

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.

Xcode: "Scene is unreachable due to lack of entry points" but can't find it

Xcode 4.5.2 gives me the following warning:
Unsupported Configuration
Scene is unreachable due to lack of entry points and does not have an identifier
for runtime access via -instantiateViewControllerWithIdentifier:.
Unfortunately I can't identify the incriminated scene. Selecting the warning in the Issue Navigator doesn't highlight anything in the Storyboard. I have a fairly complicated storyboard (30+ scenes).
Any suggestions?
In your storyboard, select each of the view controller (red arrow in image below) and look at the Storyboard ID field (red oval). None of the Storyboard ID fields should be blank. When you find one that is, that is the culprit.
While this thread is old, I didn't see an answer describing what worked for me, so here goes...
I had this error and visual examination of the storyboard showed that all of the view controllers appeared to be connected to the root view controller.
I tried naming all 17 of the view controllers in the storyboard (as in #bobnoble's answer). I used a naming convention based on the long name of the view controller, e.g. "jvc" for "Jobs View Controller". When I tried to build, I got an error message pointing to one of the view controllers as having a duplicate name. Tracking things down, I found that I had an actual duplicate of a view controller stacked exactly on top of its twin. I suspect it was cut-and-paste damage from a user interface experiment that I didn't back out completely.
Anyway, deleting the unconnected twin solved my problem. After that, I removed all of the VC names as they're not referenced in the code.
I just had this exact error with a simple single-scene Storyboard, and all I had to do to fix it was check the "Is Initial View Controller" checkbox for the 1 view controller in the Storyboard. I suspect Xcode used to check this box for you by default in this situation, but no longer does.
                                     
Check the box for exactly one of the view controllers in your storyboard and you should be good.
I'm afraid you'll have to go through all 30 of them, and check whether they have a Storyboard ID or a segue to that view controller. One of the two is required, both is also an option.
This issue can happen in one the following scenarios:
Case I:
If none of the scene in the storyboard is marked as "isInitialViewController".
Fix:
Identify the root view controller and mark it as "isInitialViewController" in your SB.
In this case storyboard id is is not mandatory.
Case II
There can be situations where you do not need to have a initialViewController in a storyboard. For eg: when using Multiple storyboards.
Fix:
In such cases make sure the "storyboard id" is correctly given and you refer to the first scene to used in the storyboard using this id. For eg:
UIStoryboard *myStoryBoard = [UIStoryboard storyboardWithName:#"MyStoryBoardName" bundle:nil];
MyViewController *myViewController = (MyViewController *)[myStoryBoard instantiateViewControllerWithIdentifier:#"MyViewControllerId"];
In this case "storyboard id" is mandatory.
Case III
You have your initialViewController connected. But still you get this warning.
This is because some of the scenes in the storyboard may not be connected with a "segue" and also they do not have a "storyboard id".
Scan your storyboard, see if a "segue" is needed. Connect the segue if that is missing.
If a segue is not needed make sure you need to give a "storyboard id" since it is the only way to refer the scene from your code, as shown in the example code above.
Hope this helps
You don't need to set Storyboard ID for all scenes or UINavigationController
Well I have around 50-60 scenes and I just got these warning so that I realise that only the controller(Scene) or NavigationController which is not connected with segue needs to set Storyboard ID.
You can see that in above image UINavigationController is not connected with segue, it was a culprit of that warning.
Just give it a Storyboard ID to remove this warning.
I had the same issue. I've got lots of views on my storyboard with a nav and tab bar controller. For me it was just be a warning to let you know that some of the views are not connected.
Make sure all your views are connected in some way to the root view controller. I was starting this project from scratch to eliminate this warning and noticed the same warning when a view wasn't connected.
Simplest way to find the offending scene:
Go to the issue navigator (in the left panel, next to the search button), and double click the error. A window will popup containing the offending scene centered in the middle of the window.
(This is actually generally true - double clicking any error will generally result in a popup containing the error centered - a neat little trick!)
Side note: Sometimes, XCode will incorrectly give this error for a scene that is the root view controller of a navigation controller (that is the initial view controller). Simple fix is giving this root view controller a Storyboard ID, compiling (error should go away), and then removing the storyboardID (no error anymore).
The easiest way to see which controller, or scene, is causing this problem is by:
Ctrl-clicking your .storyboard in the Project Navigator and selecting Open As > Source Code. This will bring up the underlying XML of the Storyboard.
In this view, the warning will be clearly related to a line in the XML that relates to the offending scene.
Now, in my case, the warning was particularly annoying because the "offending scene" had an identifier and a segue! I was able to remedy the problem by deleting the scene and then undoing the deletion. Not elegant, but worked. I saved my Storyboard before doing this. In retrospect, I should have made a copy and diff'd the before-after.
For me, it wasn't because of a Storyboard ID or a Segue. I was receiving this warning because I had not set the View Controller's Custom Class.
Select the View Controller on the Storyboard, then in the Utilities Pane, select the Identity Inspector icon. Under Custom Class, see what value is inside of the Class field.
If it just says UIViewController, then you need to type in the class name. This will be the name of your .h and .m files that make up your custom UIViewController subclass.
I came to this question today. I'm using Xcode 6.3 and the answer to the OP's question is quite simple now:
Select the View Controller you wish to be the first one, show the Attributes Inspector, and under the View Controller section, make sure
Is Initial View Controller
is checked. Voilà!
With Xcode 7 this can be handled easily. There is no need to manually go through all the scenes to find a problematic one.
First go to the Report navigator, where you can get more detail info about known issues.
Issue description can look like this:
Base.lproj/Main.storyboard:fPh-fe-F5F: warning: Scene is unreachable due to lack of entry points and does not have an identifier for runtime access via -instantiateViewControllerWithIdentifier:.
With this info, you can copy object id, in this case it was fPh-fe-F5F, and search workspace for the occurrence of this string. String will be found in Main.storyboard file. Double click on search result and it will be opened Main.storyboard with selected scene. Once you know a problematic scene you can easily fix the issue, by setting storyboard ID or setting "Is Initial View Controller"
You can just set an identifier. On the attribute inspector on the right pane, you'll find a field called "Identifier". Just put any string in there , this should work
You can click on the navigation controller and under the attributes inspector click the button "is initial view controller", and this should work too.
i faced same problem and solved with put on storyboard ID any identifier for all viewController and NavigationController also; the error will be removed immediately
enjoy!!!
Maybe this XQuery will help you to find those nasty scenes
for $i in .//scene/objects/*[1][not(#storyboardIdentifier) or #storyboardIdentifier= '']/#id (: find every scene that has an empty storyboardIdentifier :)
where count(.//segue[#destination= $i])= 0 and $i!= ./document/#initialViewController (: filter the results to the scenes that are not destinations of a segue and exclude the initialViewController :)
return ($i, $i/../#customClass) (: return the storyboard-id and the customClass, if any :)
If you have xqilla installed, you would save the query to a file and use it like
xqilla <xqueryfile> -i <path to your storyboard>
I don't know if this hasn't been mentioned yet or not but another reason you could get this warning is if you have a segue going in the wrong direction. For example, in my project I was getting this warning but all my controllers were in fact connected. However, one of them had a segue that basically was trying present the parent from the child instead of the parent presenting the child. This caused the same warning.
I got this warning when i am having a UIViewController in Storyboard to which nothing is set.
I avoided this warning by setting Storyboard ID to it.
I had the same issue,but i realized that i was using container view and instead of deleting default view controller i deleted its segue.So view controller remained in storyboard and so was the warning. So this is one of the case where warning pops up if default view controller of container view is not deleted properly when you don't need it.
I tried everything described above to no avail. I had everything connected properly in IB, with exactly one UIViewController designated the root view controller. I had no identifiers but added them to all of my controllers.
The only way I could get the warning to disappear was by doing everything above (including a computer reboot and a clean build) then switching to an error-free branch of my project in git and back again.
Unsure which action fixed it, or which combination of actions, but it wasn't the clean build on its own. This might be a byproduct of Main.storyboard always changing upon simply being opened, which means I have to git commit -m "Stupid storyboard" more often than I want to.
Here is what worked for me:
Open the storyboard in a text editor.
Change version from 3.0 to 2.0 save and close it.
Open it again in visual studio. It will automatically convert and open the document.
I got the same error : For me the error was I did not initiate a view controller in my story board.
Fixing that removed that warning.
Simply giving all MVCs a storyboard id worked for me.

Resources