Swift playground on iPadOS seems not support file operations

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Level 1

12 points

Swift playground on iPadOS seems not support file operations

I am developing an app on the iPadOS’s Swift playground. And I found that by using FileManager, I can not create/edit any file even within bundle.

my code:

func createNewFile(){

let filePath = Bundle.main.bundlePath

let fm = FileManager()

var success = fm.createFile(atPath: filePath+"/de.txt", contents: "tt".data(using: String.Encoding.utf8), attributes: nil)

print(success)

}

and the result is always false.

is it because the Swift playground on iPadOS currently do not support file operations? It can read a file from resources, but can not write.

According to what I know, it should be possible to make Swift playground on iPadOS to do file operation, because the Python interpreter on iPadOS (such as Pyto), and also C++ complier on iPadOS, etc, all can do file operations within in its app directory. I tried, no problem. It can read, write, delete files.

Best regards

Iven Dong

iPad Air, iPadOS 16

Posted on Aug 7, 2023 7:46 AM

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Answer 1

Best reply

Mark Szymczyk

Level 4

2,360 points

Aug 7, 2023 12:43 PM in response to IvenDong

You cannot save files in the app bundle. The app bundle is read-only.

You must choose a different location to save files in your app. The Application Support and Documents directories are common places to save files in iOS apps. The FileManager class has a url function that returns the URL of a directory you specify. The following code locates the user's Application Support directory:

let fileManager = FileManager.default
        
do {
  let userApplicationSupportFolder = try fileManager.url(
    for: .applicationSupportDirectory, 
    in: .userDomainMask, appropriateFor: nil, create: true)
  // Add your code to save the file here.
} catch {
  print("Failed")
}

If you want to save someplace else, replace .applicationSupportDirectory with the folder where you want to save the files.

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Answer 2

IvenDong Author

Level 1

12 points

Aug 8, 2023 6:15 AM in response to Mark Szymczyk

Hi Mark

Thanks for telling me this. You are quite helpful.

I did a try and find that all the directories are not available for iPadOS, maybe due to the sandbox techniques of iPadOS. Only these directories are available to read and write: application support, document, documentation, cache, etc.

Well, now I can do what I want. Thank you very much.

Best regards

Iven Dong

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Swift playground on iPadOS seems not support file operations

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