Failed to read values in CFPrefsPlistSource iOS 10

Question

I've updated my Xcode 8 to beta 2 today and I'm trying to share data between App and Today Extension. I'm facing with this log warning:

2016-07-08 18:00:24.732472 ProjetctX[941:42801] [User Defaults] Failed to read values in CFPrefsPlistSource<0x1700f1280> (Domain: group.x.p.t.o, User: kCFPreferencesAnyUser, ByHost: Yes, Container: (null)): Using kCFPreferencesAnyUser with a container is only allowed for System Containers, detaching from cfprefsd

Anyone can help me?

@PravinKamble I got this error, but I can access everything (user defaults's appgroup). — Klevison, Jul 12 '16 at 13:37
changing deployment target on 9.3 it will perfectly runs on the device but it won't work with iOS 10 i will be looking for solution i will be post here as soon as find solution — Pravin Kamble, Jul 13 '16 at 05:21
@PravinKamble have you created your project using Xcode 8 beta 2? — Klevison, Jul 13 '16 at 14:18
I get the same thing using shared defaults with XCode 8 beta 4. — Gruntcakes, Aug 03 '16 at 15:49
I have same issue on device (Apple Watch) only, not happening on sim with XCode 8b5. — Greg Robertson, Aug 12 '16 at 10:22
Did anyone get to the bottom of what is happening here? Still happens with XCode 8 b6. — Matt Weinecke, Aug 19 '16 at 13:12
I submitted this as a bug, hopefully it gets fixed before release. — Clay, Aug 22 '16 at 13:10
I've got the same issue in a Mac app - any idea what needs to be done? — strangetimes, Aug 23 '16 at 19:40

score 99 · Accepted Answer · edited Jun 20 '20 at 09:12

This is actually a spurious warning that was introduced in iOS 10 and macOS 10.12:

NSUserDefaults tip: in the current OSs there's a logged error "…with a container is only allowed for System Containers…".

This is spurious.

Trying to catch a particular failure mode, caught a normal operation case at the same time.

My successor on UserDefaults also has not figured out a way to make this less alarming without making the symptomatic case impossible to debug :/

https://twitter.com/Catfish_Man/status/784460565972332544 [thread]

The advice of prepending your team ID will silence the warning, but will also create a new empty user defaults. This will result in any previously stored data being unreadable.

For the time being, the solution is just to ignore it.

Also, Apple staff member CFM on the forums:

The logged message is spurious unless you're doing very specific things that I don't think are possible without using private functions (it was added to catch misuse of those functions, but unfortunately also caught a normal usage case).

I tried to create an app group that starts with the team ID but it forces it to start with 'group'. So - are the two not supposed to match??? — SAHM, Jun 01 '17 at 02:37
I'm seeing this log messages on High Sierra. Prepending the team ID does **not** silence the warning for me. Is Apple intending to fix this? — mschmidt, Jan 02 '18 at 21:26
Sorry, Can you please elaborate? "prepend your team ID" to what? — Motti Shneor, Sep 07 '19 at 17:07

score 21 · Answer 2 · edited Sep 14 '20 at 05:34

21

Here’s how to use UserDefaults with App Groups to pass data between your main app and your extension:

In your main app, select your project in the Project Navigator.
Select your main app target and choose the Capabilities tab.
Toggle the App Groups switch to ON. This will communicate with the Developer Portal in order to generate a set of entitlements.
Create a new container. According to Apple, your container ID must start with "group", so a name such as "group.io.intrepid.myapp" is perfect.
Select your extension target and repeat the process of enabling App Groups. Do not create a new App Group, simply select the group that was just created in the main app target.
When reading or writing UserDefaults in either your app or your extension, do not access UserDefaults.standard. Instead use UserDefaults(suiteName: "group.io.intrepid.myapp"). Note: The suite name is the name of your App Group container created in Step 4.

Make sure, group enable and using same group id for both extension and app capability section!

Credit goes to http://blog.intrepid.io/ios-app-extensions

edited Sep 14 '20 at 05:34

philipp

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answered Jun 12 '17 at 10:32

Arfan Mirza

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"simply select the group that was just created in the main app target" => What to do when it didn't appear ?? – user3722523 Jul 04 '17 at 18:10
enable & select same group in extension too! – Arfan Mirza Jul 04 '17 at 18:12
I repeat, how to select same group if the selection is empty in the extension ??? – user3722523 Jul 04 '17 at 18:22
When you toggle/enable groups under Compatibility section, then it auto show list of groups, if not showing then check the Team (Signing developer account), Team also need same! Set team and toggle groups again! – Arfan Mirza Jul 04 '17 at 18:27
1

it still don't work... however with iOS project it works. I'v created a thread : https://stackoverflow.com/questions/44914304/share-data-between-main-app-and-today-widget?noredirect=1#comment76810327_44914304 – user3722523 Jul 05 '17 at 09:52
close the xcode, remove build data from derived directory, then re build and execute it.. and also check your group idz are added developer.apple... panel – Arfan Mirza Jan 08 '18 at 17:27

Santiago · Answer 3 · 2020-05-02T09:53:57.713

13

Change you group name in Xcode entitlements from:

group.com.mycompany.myapp

To

group.MYTEAMID.com.mycompany.myapp

ps: you can find your MYTEAMID in developer.apple.com membership

edited May 02 '20 at 09:53

answered May 02 '20 at 08:40

Santiago

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Thank's so much. I've tried all things before. – qwerty-reloader Jul 05 '21 at 17:14
This worked for my, but why is this so important to have the team id in app groups? – adri567 Feb 14 '23 at 08:10

score 6 · Answer 4 · answered Jun 17 '18 at 01:51

6

Also had same issue with my macOS app.

Solved it by: Reboot the device!

https://stackoverflow.com/a/39876271

answered Jun 17 '18 at 01:51

Jxtt

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Surprisingly, it helped. Thanks! – DmitryKanunnikoff Apr 18 '20 at 18:29

score 6 · Answer 5 · answered May 10 '20 at 01:07

The solution for me was to not use the same identifier for the application Bundle Identifier and the part after "group.".

Say, the app bundle id is "com.app.id", then group id as "group.com.app.id" is causing issues. After I change it to "group.com.app.id.something" it stops.

score 5 · Answer 6 · answered Sep 28 '18 at 12:04

5

The SuiteName (postfix) must not be the main Bundle ID.

answered Sep 28 '18 at 12:04

Emmanuel Sellier

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score 1 · Answer 7 · answered Oct 03 '16 at 07:12

I’m facing this same issue when I’m trying to use initWithSuiteName. Seems that this is a bug from Apple. The only solution / workaround I found is to reset all the settings of the device. Go to Settings -> General -> Reset -> Reset All Settings.

This doesn’t erase any content on the iPhone, just erases all the settings. After resetting the setting, everything worked fine. Let me know if it helps you too.

score 0 · Answer 8 · answered Sep 27 '16 at 08:05

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Build with Xcode 8.1 Beta and you will see the same warning, but you will also get the value.

answered Sep 27 '16 at 08:05

raz0r

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score 0 · Answer 9 · answered Dec 01 '20 at 10:29

By default, if you are using the Settings.Bundle/Root.plist for displaying and editing your app preferences via Apple Settings App, it uses the UserDefaults.standard dictionary.

So if you are using App-Groups and you want to share this defaults / settings within your apps and extension, you need to change the container of your settings.

Step 1: Open your Settings.Bundle -> Root.plist

Step2: Add the key ApplicationGroupContainerIdentifier and as value set your App-Group-Id, defined in your Signing & Capabilities: Looks like group.xx.yy

After you have implemented this step, the default container for your App-Settings will now switch from UserDefaults.standard (your apps Path) to the Shared Path.

score 0 · Answer 10 · answered Jan 18 '21 at 14:55

Set by example

NSUserDefaults *userDefaults = [[NSUserDefaults alloc] initWithSuiteName:@"group.com.xxx.xxx"];
[userDefaults setValue:@"value" forKey:@"key"]
[userDefaults synchronize]; // return maybe false, but it doesn't matter

Get by

NSUserDefaults *userDefaults = [[NSUserDefaults alloc] init];
[userDefaults addSuiteNamed:@"group.com.xxx.xxx"];
NSString *value = [useDefaults valueForKey:@"key"];

Although the same error will still be printed when setting, the value is indeed set and can be read correctly. But I don't know why this is happening, it's just the result of various attempts.

score 0 · Answer 11 · answered Mar 15 '23 at 05:51

This issue mainly comes if the same AppGroupId apps are installed with different bundle identifiers on one device. One app has Staging, Prod, and Test environments and each environment has a different bundle identifier, but all 3 domain has the same appGroudId. So if all environment apps are installed in a single device, then UserPreferences conflicts due to the same AppGroupId.

We have seen this issue with Notification Service Extension and if we install only one environment build then it will work fine.

score 0 · Answer 12 · edited Apr 10 '23 at 16:52

0

I had this problem before. The problem is the entitlements files. The problem occurs when you change the developer account.

So first delete all the entitlements files, then go to:

Targets > Signing & Capabilities

and disable and re-enable one of the required accesses to create files automatically.

edited Apr 10 '23 at 16:52

pkamb

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answered Apr 09 '23 at 23:55

wanted

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Not helpful at all. – Codetard Apr 13 '23 at 09:43

score -4 · Answer 13 · edited Oct 24 '16 at 07:50

-4

if you suffer this problem when you try to save data to extension APP by using userDefault, maybe you had written this code:

[[NSUserDefaults standardUserDefaults] initWithSuiteName:@"group.xxx.com"];

This code reset default userDefault.

Actually,the correct code is:

[[NSUserDefaults alloc] initWithSuiteName:@"group.xxx.com"];

http://www.jianshu.com/p/e782104c3bc3

edited Oct 24 '16 at 07:50

currarpickt

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answered Oct 24 '16 at 05:22

H u Y an g

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score -10 · Answer 14 · edited Sep 08 '16 at 06:11

-10

Change from

[[NSUserDefaults alloc] initWithSuiteName:@"group.com.xxx.xxx"];

to

[[NSUserDefaults alloc] initWithSuiteName:@"nnnnnnnnnn.group.com.xxx.xxx"];

Where nnnnnnnnn is your team number, the one which you use to sign your code.

Tested under Xcode 8 GM and iOS 10 GM, and worked!

edited Sep 08 '16 at 06:11

User42

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answered Sep 08 '16 at 05:46

Titan

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Are we supposed to use "nnnnnnnnnn.group.com.xxx.xxx" for writing in the main app as well, or just use the team ID in the extension? For me, adding the team id appears to pull a blank UserDeaults without any of the data I saved to "group.com.xxx.xxx" in my app. Really hoping there is a fix to this, as it's blocking my iOS 10 update. – timgcarlson Sep 08 '16 at 18:48
2

Data still doesn't sync. Error does go away. – Jeet Sep 13 '16 at 15:03
3

currently it seems this error doesn't affect app. But if adding Team id, the error is missing but the data can't fetch. – scorpiozj Sep 18 '16 at 13:25
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This is not a good answers. You would put any thing else and skip the error as help as you change the key. – kokluch Oct 21 '16 at 08:38
Not working in my case, error disappears but data is not fetching – TibiaZ Jan 07 '19 at 11:03
You need to use "group" prefix for iOS and team ID for macOS – Tibidabo Nov 22 '19 at 22:27

Failed to read values in CFPrefsPlistSource iOS 10

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