xcode9-beta

问题 I'm trying to copy some (media) files from one folder to another using FileManager 's copyItem(at:path:) , but I'm getting the error: CFURLCopyResourcePropertyForKey failed because it was passed an URL which has no scheme Error Domain=NSCocoaErrorDomain Code=262 "The file couldn’t be opened because the specified URL type isn’t supported." I'm using Xcode 9 beta and Swift 4. let fileManager = FileManager.default let allowedMediaFiles = ["mp4", "avi"] func isMediaFile(_ file: URL) -> Bool {

问题 I'm trying to copy some (media) files from one folder to another using FileManager 's copyItem(at:path:) , but I'm getting the error: CFURLCopyResourcePropertyForKey failed because it was passed an URL which has no scheme Error Domain=NSCocoaErrorDomain Code=262 "The file couldn’t be opened because the specified URL type isn’t supported." I'm using Xcode 9 beta and Swift 4. let fileManager = FileManager.default let allowedMediaFiles = ["mp4", "avi"] func isMediaFile(_ file: URL) -> Bool {

问题 I'm running the Apple iOS11 example Adding Content to Apple Music on Xcode Version 9.0 beta 3 (9M174d) . I get a Ambiguous use of 'play() in /adding-content-to-apple-music/AppleMusicSample/Controllers/MusicPlayerManager.swift:78:9: Ambiguous use of 'play()' The suggested solutions to explicitly define the selector in order to avoid the ambiguity like: let play = #selector(musicPlayerController.play) did not work in this case. The MPMusicPlayerController instance in the MusicPlayerManager

问题 I am working on an Augmented Reality iOS app for which i am using ARKIT of iOS 11 beta. I am using ARSCNView(SceneKit) to render my .scn object. I have followed the sample given by apple in order to create an ARSession(https://developer.apple.com/sample-code/wwdc/2017/PlacingObjects.zip). Is it possible to place the 3D model with custom background instead of camera? Like user can select the background color or can provide custom 2D photos as background? 回答1: Your view has a scene property

问题 I'm using this CALayer extension: var borderUIColor: UIColor { set { self.borderColor = newValue.cgColor } get { return UIColor(cgColor: self.borderColor!) } } I thought that maybe because of this extension my borderColor of the Submit button from the bottom of the page doesn't change to white (as I want it to be): But no, I hooked up an IBOutlet and tried to set directly the color like this: submitButton.layer.borderColor = UIColor.white.cgColor Did it in viewDidLoad , viewWillAppear and

问题 In the past I had no problem creating a UIButton programmatically, but ever since I've been using Xcode 9 and Swift 4, I cannot find a way to make this error go away. //Adding target to UIButton func PositionStartButton(xOffset: Float){ StartButton.frame = CGRect(x: Int(0 - 40 + xOffset), y: 0, width: 80, height: 80) StartButton.setImage(#imageLiteral(resourceName: "Logo_Final_WHITE_Face"), for: .normal) StartButton.addTarget(self, action: "pressButton:", for: .touchUpInside) ScrollView

问题 We have big enough project which is built up with Swift 2.x and now Apple has just released Swift 4 so to move forward for latest version of Swift which path we can choose... Do we need to migrate our code to Swift 3 first? Or we can directly migrate our code to Swift 4 using Xcode 9? 回答1: Yes, you must migrate your code in Swift 3 compatible version. Xcode 9 allows conversion/migration from swift 3.0 only. Swift 3.2 is supported by Xcode 9 & Xcode 8 both. Convert your source code from Swift

问题 In previous versions of Xcode, we could hold down Alt/Option key, drag the mouse to select columns in the text editor. In Xcode 9 Beta this doesn't seem to work. Is this gone now, or is it a different key combination? Any ideas? 回答1: According to the Xcode 9 release notes it is a missing feature. I can only assume it will be added back in before the official release. From the Xcode 9 Release Notes (page 21): Xcode 9’s new source editor does not yet support discontiguous or columnar selection.

问题 I used Xcode9 Beta6 to build the project, the action was called correctly on iOS10 device, however it is not work on iOS11 device. In My project, there are some viewControllers have a UIToolBar on the top, and the toolBar contains some UIBarButtonItems. There is one this kind of viewController, whose UIBarButtonItem action is not called when I tap the UIBarButtonItem. I can see the tapping animation (the icon become dim first and back to normal after finger released) At the end of viewDidLoad

问题 I am trying to use the Lyft API with iOS 11 and Swift 4, and am receiving an error on the second line, which is Overlapping accesses to 'urlComponents', but modification requires exclusive access; consider copying to a local variable. I am unsure what this means, and how I can get around it. Any help is appreciated, thanks! let queryItems = parameters .sorted { $0.0 < $1.0 } .flatMap { components(forKey: $0, value: $1) } var urlComponents = URLComponents(url: mutableURLRequest.url!,