I've been working on a new Document-based app, and was super glad about the new UIDocumentBrowserController...trying to roll my own solution for the document browser UI was tricky!
I'm having some trouble getting the browser to open documents after they've been created.
What happens now is that when I choose to create a new document in the document browser, the document is created and opened as expected, although an error message is logged. However, after the doc is closed, I cannot reopen the file, either immediately or upon subsequent launches, even though the document is displayed. However, a weird clue here is that if I stop running the app after creating the document, but without adding new information to it (triggering the save cycle), and run the project again, I can open the file correctly. Whuch makes me think that there's something in the way the files are being saved that is the issue.
(Note: At this phase, I'm working on getting the local, non/icloud implentation working, before I move on to the icloud implementation.)
Here is the error message at any point in the code whenthe document is saved to disk (or at least most of the time!):
2017-06-20 13:21:58.254938-0500 Sermon Design 2 iOS[22454:5000138] [default] [ERROR] Could not get attribute values for item file:///Users/stevenhovater/Library/Developer/CoreSimulator/Devices/9A4364F2-B3A1-4AD9-B680-FB4BC876C707/data/Containers/Data/Application/DD534ED8-C4A3-40FE-9777-AED961976878/Documents/Untitled-9.sermon. Error: Error Domain=NSFileProviderInternalErrorDomain Code=1 "The reader is not permitted to access the URL." UserInfo={NSLocalizedDescription=The reader is not permitted to access the URL.}
I suspect that the issue lies somewher in my document types plists, which I've tried to set up by imitating the setup in the video for wwdc 2017 session 229.
My docs are encapuslated by an NSData object, using what I take to be a pretty standard subclass implentation of UIDocument. (I'm omitting the code to generate the thumbnails)
override func contents(forType typeName: String) throws -> Any {
print("Saving Document Changes")
if sermon != nil {
let newData = NSKeyedArchiver.archivedData(withRootObject: sermon!)
return newData
} else {
let newData = NSKeyedArchiver.archivedData(withRootObject: Sermon())
return newData
}
}
override func fileAttributesToWrite(to url: URL, for saveOperation: UIDocumentSaveOperation) throws -> [AnyHashable : Any] {
let thumbnail:UIImage = self.createThumbnail()
let thumbnaildict = [URLThumbnailDictionaryItem.NSThumbnail1024x1024SizeKey : thumbnail]
let dict = [URLResourceKey.thumbnailDictionaryKey:thumbnaildict]
return dict
}
override func load(fromContents contents: Any, ofType typeName: String?) throws {
guard let newSermon:Sermon = NSKeyedUnarchiver.unarchiveObject(with: contents as! Data) as? Sermon else{
throw documentErrors.invalidFile
}
self.sermon = newSermon
}
In my subclass of UIDocumentBrowserViewController, Here is my code for getting a local filename and for creating the new document.
func documentBrowser(_ controller: UIDocumentBrowserViewController, didRequestDocumentCreationWithHandler importHandler: #escaping (URL?, UIDocumentBrowserViewController.ImportMode) -> Void) {
var newDocumentURL: URL? = nil
print("creating new local document")
guard let target = self.newLocalFilename() else {
return
}
let targetSuffix = target.lastPathComponent
let tempURL = URL(fileURLWithPath: NSTemporaryDirectory() + targetSuffix)
let newDocument:SDDocument = SDDocument(fileURL: tempURL)
newDocument.sermon = Sermon()
/
newDocument.save(to: tempURL, for: .forCreating) { (saveSuccess) in
/
guard saveSuccess else {
/
importHandler(nil, .none)
return
}
/
newDocument.close(completionHandler: { (closeSuccess) in
/
guard closeSuccess else {
/
importHandler(nil, .none)
return
}
/
importHandler(tempURL, .move)
})
}
}
func newLocalFilename() -> URL? {
let fileManager = FileManager()
guard let baseURL = self.localDocumentsDirectoryURL.appendingPathComponent("Untitled")
else {return nil}
var target = baseURL.appendingPathExtension(DocumentBrowserViewController.documentExtension)
var nameSuffix = 2
while fileManager.fileExists(atPath: target.path) {
target = URL(fileURLWithPath: baseURL.path + "-\(nameSuffix).\(DocumentBrowserViewController.documentExtension)")
nameSuffix += 1
}
let targetSuffix = target.lastPathComponent
print("Target name: \(targetSuffix)")
print("new url: \(target)")
return target
}
After four or five hours of work banging my head against this problem, I discovered a simple solution: don't test in the Simulator. I switched to testing on my device and instantly everything started working as advertised.
[I can't speak from experience here, but it may be that the "doesn't work in the Simulator" problem is confined to Sierra, but that the Simulator does work in High Sierra. This would explain why some users see this issue and others don't, and especially why Apple seems blissfully unaware of it in the WWDC video.]
I had exactly the same issue when I was trying to save to NSTemporaryDirectory().
If you instead save to the documents directory ([[[NSFileManager defaultManager] URLsForDirectory:NSDocumentDirectory inDomains:NSUserDomainMask] firstObject]), it appears to work fine!
Update: it looks like this issue is fixed in iOS 11 beta 3, and you can now save newly created documents to NSTemporaryDirectory() correctly.
Here is my current theory.
This error
Error Domain=NSFileProviderInternalErrorDomain Code=1 "The reader is not permitted to access the URL."
shows up when first creating a UIDocument at a new URL using -initWithFileURL. It's basically saying "this URL doesn't exist yet," but in a way that makes it sound more like a permissions issue.
As far as I can tell, it doesn't prevent you from saving, opening, editing, or closing the file. So I think it's just a superfluous error that Apple should have taken out.
I found that the error happens on simulator when LSSupportsOpeningDocumentsInPlace property is set to YES in the info.plist.
Turn this property to NO, then it starts working, in my case.
On the real device, it works anyway without having error.
Had similar problem, and tried the method for providing a default Core Location in the Schemes settings and it works now. The method was mentioned in this answer: IOS 9 Error Domain=kCLErrorDomain Code=0 "(null)"
Related
I would appreciated some help please even if this is maybe a trivial question.
I've written a SwiftUI app that reads the media library from the device and plays it depending on user settings. That is all fine.
The problem I have is that if you install the app for the first time, the user needs to grant permission to access the media library. This appears to be a system generated dialog but I cannot see which step in the also triggers it. I tried to have the access request be triggered code generated but that doesn't seem to trigger the pop up but it still only appears at a later stage in the app load process. The code seems to recognise though that the user reacted to the access request pop up and does select the correct switch case.
What it does not seem to do though is that it still can't read the media library. The MPMediaQuery returns nil.
My suspicion is that it somehow connected to the fact that the access request doesn't run on the main thread but I am not experienced enough in Swift programming to know what the problem is. I would be most grateful for some helpful hints.
Here is my code:
import MediaPlayer
import SwiftUI
import Foundation
class Library {
var artists : [Artist] = []
#EnvironmentObject var settings : UserSettings
var counter : Float = 0
init() {
switch MPMediaLibrary.authorizationStatus() {
case .authorized:
print("authorized")
case .denied:
print("denied")
return
case .notDetermined:
print("not determined")
MPMediaLibrary.requestAuthorization() { granted in
if granted != .authorized {
return
}
}
case .restricted:
print("restricted")
#unknown default:
print("default")
}
if MPMediaLibrary.authorizationStatus() == .notDetermined { return }
let filter : Set<MPMediaPropertyPredicate> = [MPMediaPropertyPredicate(value: MPMediaType.music.rawValue, forProperty: MPMediaItemPropertyMediaType)]
let mediaQuery = MPMediaQuery(filterPredicates: filter )
var artistsInCollection : [Artist] = []
guard let _ = mediaQuery.items?.count else { return }
for item in mediaQuery.items! {
//here I do something but that's not relevant to my question
}
self.artists = artistsInCollection
}
}
I have using NSArrayController NSTableView and Core data binding.
I have take one button and connect add: method of NSArrayController to its action.
On Adding new record
TableView added and shows new record.
NSArrayController's add: method called
Problem :
Value is not added into core data (Sqlite type).
On application relaunching shows old data.
This is an apple example code. Basically it tries to save the context before app is terminated. Depending on your specific case you might move the functionality to somewhere else.
func applicationShouldTerminate(_ sender: NSApplication) -> NSApplication.TerminateReply {
// Save changes in the application's managed object context before the application terminates.
let context = persistentContainer.viewContext
if !context.commitEditing() {
NSLog("\(NSStringFromClass(type(of: self))) unable to commit editing to terminate")
return .terminateCancel
}
if !context.hasChanges {
return .terminateNow
}
do {
try context.save()
} catch {
let nserror = error as NSError
// Customize this code block to include application-specific recovery steps.
let result = sender.presentError(nserror)
if (result) {
return .terminateCancel
}
let question = NSLocalizedString("Could not save changes while quitting. Quit anyway?", comment: "Quit without saves error question message")
let info = NSLocalizedString("Quitting now will lose any changes you have made since the last successful save", comment: "Quit without saves error question info");
let quitButton = NSLocalizedString("Quit anyway", comment: "Quit anyway button title")
let cancelButton = NSLocalizedString("Cancel", comment: "Cancel button title")
let alert = NSAlert()
alert.messageText = question
alert.informativeText = info
alert.addButton(withTitle: quitButton)
alert.addButton(withTitle: cancelButton)
let answer = alert.runModal()
if answer == .alertSecondButtonReturn {
return .terminateCancel
}
}
// If we got here, it is time to quit.
return .terminateNow
}
You're probably missing setting the managedObjectContext and entityName on NSArrayController.
I am using WebRTC and its using AVCaptureSession. It works fine a few times but sometimes its getting crashed with this Exception.
Assertion failed: (_internal->figCaptureSession == NULL), function
-[AVCaptureVideoPreviewLayer attachToFigCaptureSession:], file /BuildRoot/Library/Caches/com.apple.xbs/Sources/EmbeddedAVFoundation/EmbeddedAVFoundation-1187.37.2.1/Aspen/AVCaptureVideoPreviewLayer.m
I recently had this problem aswell. In my code i kept an instance of AVCaptureOutput and added and removed it. When trying to add the same AVCaptureOutput instance to the same capture session again, this error appeared.
This is how i solved it:
private var _captureOutput: AVCaptureOutput?
var captureOutput: AVCaptureOutput {
guard let captureOutput = _captureOutput else {
let photoOutput = AVCapturePhotoOutput()
photoOutput.isHighResolutionCaptureEnabled = true
_captureOutput = photoOutput
return photoOutput
}
return captureOutput
}
Initialize the instance once when needed and when removed, also nullify it.
captureSession.outputs.forEach { [weak self] output in
self?.captureSession.removeOutput(output)
self?._captureOutput = nil
}
Before using instance of RTCCameraPreviewView you have to nill'ify its captureSession and assert will go away. Faced same issue.
I've been working on a BIG project (there's no point of showing any actual code anyway) and I've notice that the following message appears in the logs:
CoreText CopyFontsForRequest received mig IPC error (FFFFFFFFFFFFFECC) from font server
The error pops up as soon as a WebView has finished loading. And I kinda believe it's the culprit behind a tiny lag.
Why is that happening? What can I do to fix this?
P.S. Tried the suggested solution here to check whether it was something system-specific, but it didn't work.
More details:
The error appears when using the AMEditorAppearance.car NSAppearance file, from the Appearance Maker project. Disabling it (= not loading it all) makes the error go away.
I don't really care about the error message, other than that it creates some weird issues with fonts. E.g. NSAlert panels, with input fiels, show a noticeable flicker and the font/text seems rather messed up, in a way I'm not sure I can accurately describe. (I could post a video with that if that'd help)
This is probably related to system font conflicts and can easily be fixed:
Open Font book
Select all fonts
Go to the file menu and select "Validate fonts"
Resolve all font conflicts (by removing duplets).
Source: Andreas Wacker
Answer by #Abrax5 is excellent. I just wanted to add my experience with this problem and could not fit it into a comment:
As far as I can tell, this error is raised only on the first failed attempt to initialise an NSFont with a font name that is not available. NSFont initialisers are failable and will return nil in such a case at which time you have an opportunity to do something about it.
You can check whether a font by a given name is available using:
NSFontDescriptor(fontAttributes: [NSFontNameAttribute: "<font name>"]).matchingFontDescriptorWithMandatoryKeys([NSFontNameAttribute]) != nil
Unfortunately, this also raises the error! The following method does not, but is deprecated:
let fontDescr = NSFontDescriptor(fontAttributes: [NSFontNameAttribute: "<font name>"])
let isAvailable = NSFontManager.sharedFontManager().availableFontNamesMatchingFontDescriptor(fontDescr)?.count ?? 0 > 0
So the only way I found of checking the availability of a font of a given name without raising that error is as follows:
public extension NSFont {
private static let availableFonts = (NSFontManager.sharedFontManager().availableFonts as? [String]).map { Set($0) }
public class func available(fontName: String) -> Bool {
return NSFont.availableFonts?.contains(fontName) ?? false
}
}
For example:
NSFont.available("Georgia") //--> true
NSFont.available("WTF?") //--> false
(I'm probably overly cautious with that optional constant there and if you are so inclined you can convert the returned [AnyObject] using as! [String]...)
Note that for the sake of efficiency this will not update until the app is started again, i.e. any fonts installed during the app's run will not be matched. If this is an important issue for your particular app, just turn the constant into a computed property:
public extension NSFont {
private static var allAvailable: Set<String>? {
return (NSFontManager.sharedFontManager().availableFonts as? [String]).map { Set($0) }
}
private static let allAvailableAtStart = allAvailable
public class func available(fontName: String) -> Bool {
return NSFont.allAvailable?.contains(fontName) ?? false
}
public class func availableAtStart(fontName: String) -> Bool {
return NSFont.allAvailableAtStart?.contains(fontName) ?? false
}
}
On my machine available(:) takes 0.006s. Of course, availableAtStart(:) takes virtually no time on all but the first call...
This is caused by calling NSFont fontWithFamily: with a family name argument which is not available on the system from within Chromium's renderer process. When Chromium's sandbox is active this call triggers the CoreText error that you're observing.
It happens during matching CSS font family names against locally installed system fonts.
Probably you were working on a Chromium-derived project. More info can be found in Chromium Bug 452849.
I have a NSDocument subclass that presents a text document from disk. I’m trying to make it refresh automatically on detecting file changes on disk. I’ve overridden -presentedItemDidChange like this:
- (void)presentedItemDidChange
{
[super presentedItemDidChange];
// Ignoring bundles and error-handling for the moment.
NSData *newData = [NSData dataWithContentsOfURL:self.presentedItemURL];
self.textView.string = [[NSString alloc] initWithData:newData encoding:NSUTF8StringEncoding];
}
The UI refreshes fine when the file is changed in another application. The problem is, I get this dialog when I try to save the document in my application after it is modified by another app:
I kind of have an idea why this happens (not sure whether it’s correct): The modification time of the document is later (because it’s modified by another application) than the latest saved version in my app. But can I notify the autosaving system that I have done something with it and let it go away? Or am I doing things wrong when I refresh the document, and I should do it some other way to handle document versions correctly? I need to consider both external applications support or do not support autosave.
Thanks in advance.
#uranusjr's answer pointed me in the right direction -- only revertDocumentToSaved: wasn't exactly the right place.
override func presentedItemDidChange() {
dispatch_async(dispatch_get_main_queue()) {
self.reloadFromFile()
}
}
func reloadFromFile() {
guard let fileURL = self.fileURL else { return }
do {
try revertToContentsOfURL(fileURL, ofType: "YOUR TYPE HERE IF NECESSARY")
} catch {
// TODO handle error
print(error)
}
}
This simply reloads the file. readFromURL(url:, ofType:) (or the NSData/file wrapper based variants) is called and you can re-create your data structures from there.
Stumbled across the solution today (finally). You can “cheat” OS X into not warning about this by reverting the document (but not the file itself) before actually updating the internal data structure:
// Somehow read the updated data.
NSString *content = ...;
// Revert the document.
// This will discard any user input after the last document save,
// so you might want to present some UI here, like an NSAlert.
[self revertDocumentToSaved:self];
// Update the internal state.
self.content = content;
Now OS X will be happy when you save the document.