The server I'm working with returns a date/time string that is always expressed in US central time. There is no timezone information in the string itself. In order to parse this string, I need to create a DateFormatter and then assign its timeZone property. I'm having trouble figuring out the right way to do this. I know that the correct string that means US central time is "America/Chicago", but it appears that the TimeZone initializer is looking for an abbreviation, rather than a full string. I don't know what the correct abbreviation is. I don't want to use "CST" or "CDT" since those denote standard or daylight time. I need something that means whatever the current timzeone is in Chicago. In Java, as an example, the Timezone class accepts "America/Chicago" as an initializer and it works whether or not the calendar is on daylight savings time. Thanks, Frank

I'm using Sign In with Apple and requesting both .fullname and .email. The first time I sign in on any given device, the callback to my app has an authorization credential that contains an email address and a fullname, as expected. However, any subsequent login on the same device does not return either the email address or the fullname. All I get is the user ID string. The server I'm working with requires an email address to log in, so I need that email address. Why does it only appear the first time? Frank

I'm trying to figure out the right way to format a Decimal number as a currency value in Swift. For example, if the Decimal contains the value 25.1 I'd want this to print as "$25.10". If it had the value 25, I'd want "$25.00". If it happened to contain a value like 25.4575, I'd want to round it off and display "$25.46". There are a confusing amount of functions surrounding Decimals and string formatting. I know I can't just use String(format: "%.2f", value) like I can do with floats and doubles. There appears to be a new FormatStyle property of Decimal, but I can't use that yet because it requires iOS 15. Thanks, Frank

I need to do something that seems simple but I can't figure out the right syntax. Given a string, I need to search for the first occurrence of a substring (not a character). If found, I need to create a new string by removing the part of the old string that is before the substring. I can't see how this is done in Swift. There is a "firstIndexOf" function, but it only searches for one character at a time. I also know that there is a "range(of:)" function, but I can't find its documentation, and I don't know what the return type is, or how I would use it. 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.

I need to decode JSON into a class. The JSON has a field called "Type", and I cannot declare a property with that name in my class since Type is a reserved word. I tried declaring CodingKeys, but that doesn't work unless I declare EVERY property in the CodingKeys. This class has about a hundred properties and I have others like it, I do not want to do this. Is there a better solution?

I'm building a custom camera screen that displays the camera image on a preview layer and then captures an image, using AVCaptureSession. When the picture is captured, I immediately load it into a UIImageView in order to display it to the user for approval. I've actually done this many times before, but this is the first time I've tried to do it in an app that supports interface rotation. If I hold the phone in Portrait mode and capture a picture, everything works as expected. When the user rotates the phone into Landscape orientation, I detect this and I replace the preview layer (AVCaptureVideoPreviewLayer) with a new one, specifying connection.videoRotationAngle in order to make the image appear in the right orientation. I'm a little surprised that this is necessary, and it's not a smooth transition, but that doesn't matter. What does matter is that when I capture the image, it is in the wrong orientation. I tried rotating it myself, but this doesn't seem to make any difference. What am I doing wrong?

Hi,Usually when you create a new class or other file in Xcode, the default location of the new file is a folder with the same name as your project.Somehow, I've ended up with a project where the default location for new files is the folder above this (the one with the .xcodeproj file in it). I can certainly change the folder whenever I make a new file, if I remember to do it, but often I forget, and end up with half my files in one place and half in the other.What controls this default, and how can I change it back to the folder I want?Thanks.

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

I've always understood it to be the case that apps could permit users to log in or use a code to access paid content, as long as the app did not direct the user to an external web site to make a purchase. For example, apps like Netflix or Kindle.My app isn't even doing anything close to this. I have an app in which digital content is unlocked via in-app purchase. Occasionally I give away promo codes that allow a user to unlock one free piece of content. These codes can only be used once, and are distributed in very limited numbers on cards, in person, at events like trade shows.My app has been in the store for about four years using this method. This week I attempted to publish a small bug-fix update, and was flagged by Apple and told that my use of Promo Codes in this manner violates the rules.What happened here? Did Apple misunderstand what my app is doing? Did the rules change recently and I was unaware of the change? Has this always been against the rules, but either Apple didn't enforce it before or they never reviewed my app thorougly enough to find it?Thanks,Frank

Hi,I have an app that includes a very simple one-button interface for recording a video. Our customer wants to be able to switch between the front and rear cameras while the video is being recorded, and without any interruption in the video stream. I notice that even the iOS built-in camera app doesn't do this, but I've heard that some third-party apps do.Is this possible in a practical way? If so, how would I go about it?Thanks,Frank

I'm getting this message when I try to install Xcode, it says there is not enough disk space.I checked my main volume and there is 60GB available.I'm assuming that Xcode can't possibly require more than 60GB and that this message is a mistake. How do I fix it?Thanks,Frank

I've seen examples of Swift code with #if DEBUG / #endif, and have even used it myself.I know exactly how preprocessor macros work in c, c++ and Objective-C. In those languages, I know I can say:#ifdef DEBUG ... some code ...#endifAnd I know that if the DEBUG flag is false at build time, the code will not only not run, but it won't even be compiled. This is important to me because the code inside that block contains some sensitive information that must not end up in my compiled code for non-debug builds.In Swift, I'm really not sure what happens. I know the code doesn't execute, but I'm also told that Swift doesn't have a preprocessor. So, what exactly is going on here?Specifically, can I hide sensitive information inside an #if DEBUG block in Swift and be assured that it won't get compiled or in any way be present in the executable when the DEBUG flag is false? Or is #if DEBUG evaluated at runtime in Swift?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 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?