Xcode Playgrounds: Source files are unable to be accessed by each other - swift

I am creating a playground in Xcode and I do not understand why the "Sources" files cannot talk to each other. I am using SpriteKit which means it is ideal to have one swift file per scene, in my case I have one scene per level. I cannot use a quick workaround and add everything into one massive file... there has to be a better way. Both classes for the two swift files are public. You should be able to access them. Thanks!
I get this error when I try to an object from one class, LevelScene, in the other class TitleScene.
After this
let levelScene = LevelScene(fileNamed: "LevelScene")
This happens
Cannot find 'LevelScene' in scope
I am aware of this post. This solution still does not work for me.
Xcode playgrounds can't access swift files in Sources folder
I am on Xcode 12.4.
Thanks!

You need to declare all your classes/struct in each file as public.
So, if you have defined a struct like this in a file:
struct Node {
var id: Int
}
You need to declare is like so:
public struct Node {
var id: Int
}
Then your code should work. You can use a struct from one file in another file as long as you declare them as public. Similar concept goes for any functions/methods inside those structs/classes. Even with this solution, you may find Xcode 12.4 complaining about not finding the type in scope. That, I believe, is a known bug. I have the same bug on my Xcode 12.4. I am able to build and run the code even with that error.

Related

Swift public func not being exported from framework

I created a Swift Framework project in Xcode and I'm trying to export a function for Unity to call. I defined the function like this.
#_cdecl("showPaymentForm")
public func showPaymentSheet()-> PKPaymentAuthorizationViewController?{
NSLog("In showPaymentForm - Navtive code.")
return ApplePayLib.showPaymentSheet(label: "something", total: 9.99, mainViewController: nil)
I ran
nm -gU
against the binary and it doesn't show any functions exported called showPaymentForm. I check the "Symbols Hidden by Default" to make sure it was set to "No".
If I do the same as above in a package instead of a framework, it works fine. I didn't stick with the package project because I need to include other packages that didn't play nice with it.
Not really sure what else to check.
It turned out the issue was due to the swift file not having a target selected. Once I selected the correct target, the function as exported correctly.

How to get coverage for private init

The context
In a framework I'm currently building, I am using multiple structs (example) to store String constants. Let's say one looked like this:
public struct SpecificConstants {
private init() {}
public static let foo: String = "foo"
}
This is all nice and well. You can use the constant, it doesn't clutter global namespace, the struct name states the specific purpose of the constants which are defined in it.
Also, by making init() private, it is made clear inside the framework (it's open source) and outside of it that this struct should not be instantiated. It wouldn't hurt if you were to create an instance of it but it would also have no use at all. Also, the init would show up in autocomplete if it weren't private, which would annoy me :)
The problem
I'm proudly writing a lot of tests for the framework and I'm using Xcode's internal coverage reporting (llvm cov). Unfortunately, this coverage reporting shows the init as 'not covered':
This is completely logical, since the init isn't being run by the tests, because it can't be.
To my distress, this prevents me from getting the good ol' 100% coverage.
Possible solutions
I could use lcov, which would enable me to use LCOV_EXCL_LINE or LCOV_EXCL_START and LCOV_EXCL_STOP to exclude the inits from the coverage.
Why not: I'd love not having to setup a different coverage tool when there's already a builtin tool in Xcode.
I could make the inits internally accessible so I could gain access to them inside my unit tests by importing the module as #testable.
Why not: Though they would still be inaccessible from outside the framework, they would now be visible inside the framework, which I don't like. I'd like them to be darn private :D
I could live with my coverage never reaching 100%.
Why not: Because I just can't :).
The question
Is there any way (I could live with it being a bit, even quite hacky) to run this forsaken init in my unit tests while keeping it inaccessible from outside as well as inside the framework?
Move your String constants to an enum then you won't need a private init.
enum SpecificConstants {
static let foo = "foo"
}

Binding in OSX: class is not key value coding-compliant for the key {name of binding var}

I was trying to follow instructions from Learning Swift book (creating note taking app) by B.A. Paris & Co, but faced with the following problem with binding. I am mostly practicing iOS programming, so binding concept is new for me.
Steps I made (tried both xcode 9 beta 5 and 8.3.3):
Create OSX Cocoa App (not using storyboard, document based app – on, document
extension “test”, don’t use core data)
Add “var text = NSAttributedString()” to Document.swift
Add a NSTextView to Document.xib
In Bindings inspector of NSTextView setting “Attributed String” to File’s owner “self.text” (Model Key Path)
And I see exclamation mark with notion “Xcode cannot resolve the entered key path”
Build is successful, but when I run it says “2017-09-03 22:17:40.739643+0200 test3[6017:424072] [<test3.Document 0x6180000c3410> valueForUndefinedKey:]: this class is not key value coding-compliant for the key text.”
I tried to control drag from Xib to Swift, it warns that “Xcode cannot locate the class Document in the current workspace”.
I tried to convert to workspace instead of proj, checked the file owner, checked the stackoverflow threads witch relate to the error – but they mostly concerned about some connection made by mistake or non actual connections (I can delete the connection, I know what connection is wrong, the question is how to make it right). So far could not find solution.
Thanks in advance
You need to declare the text property with the #objc attribute to make it accessible via dynamic dispatch like Key-Value Coding.
Also, because you want modifications of the property to be observable via Key-Value Observing (for Bindings), you need to tell Swift to always dispatch modifications of it dynamically. So, you need to use the dynamic modifier on the declaration, too:
#objc dynamic var text = NSAttributedString()

Importing classes from playground page into another page

Note: This is a different question than importing generic swift files (which can be done using the Sources folder).
I have a playground with 2 pages and I would like to use a protocol defined in the first page in the second page. I'll use an example of JSON conversion.
JSON.xcplaygroundpage
import Foundation
protocol JSONConvertible {
func jsonValue() -> String
}
JSONArray.xcplaygroundpage
import Foundation
//Undeclared type JSONConvertible
extension Array : JSONConvertible {
}
I have tried the following imports:
import MyPlayground
import MyPlayground.JSON
import JSON
import JSON.Contents (in finder the file name is actually Contents.swift)
I have also tried adding JSON.xcplaygroundpage into the Source folder of JSONArray as well as the Resources folder.
Note: I realize that I could put the protocol definition in a separate JSON.swift and include that in my project Sources folder. That doesn't really answer my question.
This is working in Xcode 8.3.3.
For code common to multiple pages, put it in separate files under top-level Sources group. Be sure to have proper Swift access control keywords in the right places.
Note from http://help.apple.com/xcode/mac/8.2/#/devfa5bea3af:
...the auxiliary Swift source file must export it using the public keyword. This includes classes, methods, functions, variables, and protocols.
Common.swift:
public class DoIExist { public init(){ print("Woot!")} }
Then you can reference it in all of the other pages. Like this:
Page2:
//: [Previous](#previous)
let d = DoIExist()
//: [Next](#next)
You can see that it works because of the console output ("Woot!") and the view results gutter.
To achieve this, I followed the directions at the Apple Xcode documentation about Playgrounds. When Apple inevitably moves those docs and does not provide a forwarding link, read on for how I found it.
I searched for the clues found in the link in cocoapriest's answer: "ios recipes Playground Help Add Auxilliary Code to a Playground". This leads to a document Apple is currently calling "Xcode Help" in a chapter titled "Use playgrounds" in a section titled "Add auxiliary code to a playground".
Just got this to work with this instruction by Apple: https://developer.apple.com/library/ios/recipes/Playground_Help/Chapters/AddAuxilliaryCodetoaPlayground.html
Make sure to declare your classes are public. Also, I had to re-start the Xcode to take the effect.

FileA.Swift <--> FileB.Swift Scope: Accessing public entities

Is there a way to access typealias, functions, classes and structs defined in one .swift file from another .swift file?
I attempted to access a public func() and public class() defined in one .swift file from a different .swift file but failed:
Environment.swift:
MainViewController.swift:
Apparently my Xcode project got corrupt.
I created a new project and repeated the pattern.
...occasionally, I find that a Xcode/Swift project appear to work like a 'loose light bulb' that needs to be tweaked/cleansed... or replaced to have a working solution.
This time it works.