I've got an iOS project that I've been working on for some months. Just recently, I started seeing a compiler error to the effect that "Referencing instance requires that X conforms to Equatable". It shows up in places where you'd expect something to be Equatable, such as the argument to firstIndexOf: on an array. The class in question is written in Swift, but descents from an Objective-C base class. I know there are some issues with how Equatable interacts with Obj-C but I think I've done it right. The base class extends NSObject, and the subclass implements both the isEqual function and the static == function. (I don't think the latter is necessary but I included it just in case). I've tried explicitly including "Equatable" in the definition of the subclass but the compiler rejects this as "Redundant conformance to protocol". I'm not exactly sure how that works since NSObject doesn't extend Equatable but I guess Swift considers them equivalent. Here's where things get super weird though. Xcode still builds and runs the project despite the compiler error, and the code runs, and it works. I even put a breakpoint in the isEqual function to make sure it was getting called. Also, when I clean and rebuild the project, the compiler error often disappears for some time, reappearing hours or days later. So I think this must be some kind of bug in Xcode or Swift itself. What do you think? Frank

I can't get my latest iPhone app to run in portrait mode only. In Xcode I've checked only the box that says "Portrait" under Device Orientation, and I've also examined the Info.plist file to ensure that there aren't any hidden settings for other orientations. I've also tried checking or un-checking iPad, and checking "Requires Full Screen" when that option appears. No matter what I do, when I run the app on my phone and rotate the screen, the interface rotates. What am I doing wrong?

Views A and B are equal in width (set up via a constraint). The actual width will vary at runtime. What I want to do is arrange view A such that it is horizontally centered on B but offset to the left by 1/10th of the total width. In other words, if views A and B were 100 units in length, I'd want A to be positioned 10 units to the left of B. If the width were 150 units then the A position would be 15 to the left, etc. I thought I could do this with either a leading constraint or a centerX constraint using a multiplier of 0.9, but it isn't working out the way I want. What's the best solution?

Hi,I have an app that was approved and is "Pending developer release".While we were waiting to release the app, someone found a bug that we'd like to fix.Unfortunately, I can neither upload a new version of the app, nor create a new version in iTunes Connect (the option to add a new iOS version is disabled).Is there any way to revoke the approved version without releasing it to the app store? I don't mind having to wait for Apple to review the updated version again.Frank

I want to customize or limit the typing suggestions for a UISearchBar input to a list of known words that exist within the material that is being searched. How is this done? Thanks, Frank

How do I disable the predictive text feature (word suggestions) of the keyboard when used with a UISearchBar?

Do string functions such as "replacingOccurrences" and "trimmingCharacters" always return a new string, even if the old string did not need to be modified? In other words -- if I'm doing a large number of "replacingOccurrences" in my app but only a small number of the strings actually contain the sequence I want to replace, should I check to see if the sequence exists before calling replacingOccurrences, in order to avoid an unnecessary string allocation? I would guess that Swift would return the same string if it didn't require any modifications, but the documentation just says "Returns a new string". Thanks, Frank

We have an auto-renewable subscription in our app that we want to stop offering. However, we want to make sure that people who have already purchased the subscription remain subscribed until the end of their current subscription period (and are subsequently unsubscribed and not charged further). What is the right way to do this?We tried submitting the app with the subscription still enabled in App Store Connect but hidden in the app, and our update was rejected because the reviewer couldn't find a way to subscribe.Thanks,Frank

I'm getting the dreaded "Failed to prepare the device for development" error when I connect my iPhone running iOS 15 to the latest version of Xcode. I've tried rebooting both devices. How do I fix this?

I'm trying to save a Dictionary to UserDefaults. My Dictionary is defined as [String:Data]. Since both String and Data are property objects, I expected this to work, but it doesn't: my app blows up with a "this class is not key-value coding compliant" error. Is this a bug, or am I doing something wrong?

Hi,I'm familiar with the "willTransition" method of view controllers that lets you detect when a transition to a new UITraitCollection is about to begin.What I need is a callback that happens after the transition is finished. There doesn't seem to be any "didTransition" method, nor any delegate property on the UIViewControllerTransitionCoordinator that I can use for this.How does one obtain this callback?Thanks,Frank

How do I get a background image to fill the screen in my launch screen on an iPhone X?I have aligned the image to the top and bottom layout guides, but this leaves large white gaps.

Hi,How do I check to see if a Character is in a Character Set?In Objective-C, I could write:[[NSCharacterSet lowercaseLetterCharacterSet] characterIsMember:c]Where "c" is a variable of type char.In Swift, I tried to write:CharacterSet.lowercaseLetters.contains(c)Where "c" is of type Character, but I received an error saying that the function was expecting a parameter of type "Unicode.Scalar".Thanks,Frank

Hi, My customer wants to do the thing where an app store URL is advertised which contains a referral code. When a user follows the link, it should take them to the app store to install the app, and then when the app is installed, it should be able to get access to the referral code in the original URL. I know such a thing was possible at one time because I remember talking to some of my colleagues about it, but I have never done it myself and whatever my coworkers did 8 years ago in Objective-C probably doesn't work anymore. Can someone let me know how to do this, or at least, let me know what the correct name for this procedure is so I can look it up? Thanks.

A customer added me to their team today as a developer.When I sign in to App Store Connect, I can see and select their team from the list that appears under my name. However, when I open Xcode, the team doesn't appear under my Apple ID in Account Preferences or in the Team drop-down in the signing tab.I also noticed that even though I can select the team in App Store Connect, my name doesn't appear on the Users and Access screen. But I can see the app that I was assigned to work on.I tried closing and opening Xcode several times. I also removed and re-added my Apple ID.I waited several hours in case this was some sort of data propagation issue, but it hasn't resolved. What should I do next?Frank