I was just testing my code in play ground(xcode-8.2), using swift tutorial. I came across following sample code:
One-Sided Ranges
for name in names[2...] {
print(name)
}
now my play ground showing an error:
now I feel that my swift version may not be supporting this code!
I looked around this answer but it provide solution for Xcode Project only.
How do I see which version of Swift I'm using?
How can I see swift version of play ground?
Try to find out swift version using following code. (Here I tried this code with Playground of Xcode 9.3 - beta 4) and it's providing me correct answer.
#if swift(>=5.2)
print("Hello, Swift 5.2")
#elseif swift(>=5.1)
print("Hello, Swift 5.1")
#elseif swift(>=5.0)
print("Hello, Swift 5.0")
#elseif swift(>=4.1)
print("Hello, Swift 4.1")
#elseif swift(>=4.0)
print("Hello, Swift 4.0")
#elseif swift(>=3.0)
print("Hello, Swift 3.x")
#else
print("Hello, Swift 2.2")
#endif
Answer to your question: I'm not sure but according to result of above code, I can say, Latest Swift version supported by your Xcode tool becomes a version of Playground's Swift Language.
By default Playground use the Swift version based on your Xcode version
You can check the Swift version by Xcode release here
https://swift.org/download/#releases
In the terminal run
swift -version
in all probability playgrounds will be using that version
Related
I want to use a module (SwiftyStoreKit) which has a minimum requirement of WatchOS 6.2, however I don't want to increase my WatchOS target because I don't want to lose support for older watches. My understanding is that Swift now has conditional imports which will let you import a module only in the OS allows the import but the below code is not working? I'm still getting a compiling error "Compiling for watchOS 4.3, but module 'SwiftyStoreKit' has a minimum deployment target of watchOS 6.2:" and if I remove "import SwiftyStoreKit" the module isn't detected.
#if canImport(SwiftyStoreKit)
import SwiftyStoreKit
class SwiftyStoreKitWatchHelper {
}
#endif
Try this
#if canImport(SwiftyStoreKit)
import SwiftyStoreKit
#endif
#available(watchOS 6.2)
class SwiftyStoreKitWatchHelper {
}
When archiving/building the app which uses SwiftUI for platforms <= iOS 10, the compiler throws errors "Use of undeclared type".
This happens even if the enclosing type is marked as #available(iOS 13.0, *) and also using #if canImport(SwiftUI).
SwiftUI framework is also weakly linked.
Everything works fine if you are running(debug) on an iOS 11+ device, or archiving for a target with minimum supported version <= iOS 11.
This failure occurs because builds with a deployment target earlier than iOS 11 will also build for the armv7 architecture, and there is no armv7 swiftmodule for SwiftUI in the iOS SDK because the OS version in which it was first introduced (iOS 13) does not support armv7 anymore.
I have managed to solve the archiving issue by wrapping the SwiftUI Code/Files in the preprocessor of #if arch(arm64).
Example -
#if arch(arm64)
#available(iOS 13.0, *)
struct MyCustomView: View {
var myStrings: [String]
var body: some View {
List {
ForEach(myStrings) { str in
Text(str)
}
}
}
}
#endif
This does disable previews in cases if your deployment target is <= iOS 10.
But if used only when archiving, this does work.
If anyone knows of a better solution. Please share.
Adding this answer so that someone in my situation can atleast make it work with SwiftUI.
Cheers!
RealityKit is only available on iOS 13.0 and up and when I try to integrate it to my project and run it on iOS 12.0 or below, the app crashes with abort_with_payload error.
I still want my app to run on iOS 9.0 - iOS 12.0 without the AR feature. Is there a way I can do that?
This happens because the framework RealityKit always imports even though the device does not have that framework. The solution is to make it optional based on the device you are using.
Go to you project's Build Settings.
Go to Linking -> Other linker Flags
Double click Other linker Flags values to add a new one.
Press add button then type -weak_framework RealityKit
That should do it. Enter then run your app.
Hope this helps. Happy Coding. :D
Have a look at the canImport(module) directive
#if canImport(RealityKit)
import RealityKit
#endif
#available(iOS 13.0, *)
class MyClassWhichUsesRealityKit {
func do() {
let v = ARView(frame: .zero)
}
}
Source: https://github.com/apple/swift-evolution/blob/master/proposals/0075-import-test.md
There is a new logging system in iOS 10 and macOS Sierra.
But I can't seem to make it work in Xcode. os_log is not recognized, and neither is any other function / constant mentioned in the docs.
Use of unresolved identifier 'os_log'
Do I need to link a framework or import a header or something? Am I missing something obvious?
In Swift:
import os
os_log("Some message")
In Objective-C:
#import <os/log.h>
os_log(OS_LOG_DEFAULT, "Some message");
I'm getting a couple of errors when creating my tvOS target from my Sprite Kit iOS game.
The first is: Could not build Objective-C module CoreMotion
Second: Umbrella header "CoreMotion.h" not found
In order to port the game, I've selected most of my files and assets from the iOS target and checked the TVOS target.
If I comment out all of the CoreMotion code, then the errors go away. I've searched Google and here to find an answer, but didn't find anything substantial.
Anyone know how to solve this?
The problem was the tvOS doesn't support CoreMotion.
I had to use iOS specific code to make it work for all relevant code.
Like so:
#if os(iOS)
import CoreMotion
#endif
You could also make tvOS specific code:
#if os(iOS)
let gameGain: CGFloat = 2.5
#elseif os(tvOS) // tvOS
let gameGain: CGFloat = 2.0
#endif