Dev:Updating extensions for iOS 8

Let's collect knowledge like we did with iOS 7 - paste in your notes and share what you've learned, and somebody else will organize it later. :) If you want to ask questions and share tips over chat with other developers, see How to use IRC for how to connect to #theos and #iphonedev.

It's also helpful to double-check the statements here and add more info! These are notes and drafts from early research - feel free to update them.

= What has changed in iOS 8? (Classes, frameworks, etc.) =

Preference saving
In iOS 8 (and above), the preferences daemon cfprefsd is handling all preferences in memory and writes them to the corresponding .plist file lately (it synchronizes data every 10 seconds, as specified in  in CoreFoundation framework). Therefore when the notification for a change is posted, the change is usually not yet written to the file. Reading preferences directly from the .plist has become problematic. The notification from the Preferences specifier plist is now posted before the plist is updated on disk — as opposed to after the plist was updated on disk, which was the case on iOS < 8.

Writing directly to a plist in Preferences is also a problem because then the daemon will not know about your "manual" changes, and will overwrite those changes when it writes its in-memory settings. So either you read or write everything yourself (for example by overriding setPreferenceValue:specifier: and readPreferenceValue:) or use CFPreferencesUtils.

Solution 1: Use CFPreferences (does not work in sandboxed processes)
See Loading Preferences into unsandboxed processes (using CFPreferences) for what to do. (As that page says: this was tested back to iOS 6, it seemed to work without problems. This solution does not work if you are in third party apps or other apps that have sandboxed preferences.) Another viable option could be using GCD and using a descriptor source for that file.

Solution 2: Override setPreferenceValue:specifier and readPreferenceValue: in preference bundle to restore old behaviour (Karen (angelXwind)'s method)
See Loading Preferences into sandboxed/unsandboxed processes in iOS 8 for instructions and code on how to achieve this.

I've tested this on iOS 5, 6, 7, and 8, and can confirm that it works without any issues.

Solution 3: Use CFPreferencesAppSynchronize (apparently works in sandboxed processes for some people) (iMokhles/ichitaso's method)
See How to use CFPreferencesAppSynchronize with ARC and non ARC (iOS8 Tweaks) + CFNotificationCallback for some example code.

Above example tested with Sandbox Apps "WhatsApp" and "Tweetbot 3" and seems to work perfectly.

Solution 5: Use NSUserDefaults (Private API)
Another way on the sharedInstance blog.

Note on previous iOS versions the preference wasn't always up to date but on iOS 8 it appears to be. Using this in my StealthCam SpringBoard tweak. Doesn't work within a sandbox.

Thanks to xTM3x, Yllier, and others for their research on this.

Application related

 * The term 'Display Identifier' has been removed when referring to SBApplication. Methods that used the term usually have a 'Bundle Identifier' equivalent; e.g.  and   are now   (as opposed to  ) and  . Since applications are now found using their bundle identifier,   is now  . A catch-all way of getting *any* icon is,.


 * MISValidateSignatureAndCopyInfo appears to perform additional code-signing checks during app installation.


 * Mobile application containers are at  and their data are located at  . Using AppList you can get the path to the bundle and data of an app from its bundle id with the following code:

See TM2406.


 * Looks like certain apps don't have privileges for IORegistryEntryCreateCFProperty anymore (Safari, Mail).


 * If an app is using WKWebViews, processes named com.apple.WebContent and com.apple.WebNetworking are being spawned and they each create only one NSURLCache. If you want to know the bundleIdentifier of the app they were spawned for, just hook  in those processes. relativePath will be that bundleIdentifier. It's not perfect but a quick and neat trick.


 * com.apple.mobileinstallation.plist is gone on iOS 8. You can use AppList to get a list of installed apps. If you need to do this without Substrate for some reason, this post and thread has some discussion of alternatives.


 * SBAppSlider* classes have been renamed to SBAppSwitcher*

Daemons

 * launchctl appears to be slightly broken. launchctl start and stop work perfectly, but launchctl load/unload no longer works with daemons in /System/Library/LaunchDaemons/ (aborts with the cryptic error message ). But you can load/unload daemons based in /Library/LaunchDaemons/ (that's where you are supposed to launch your daemons from anyway).
 * Use the new params e.g.


 * installd cannot be reloaded via launchctl.


 * Notes from iOS 8 and the OS X 10.10 Preview, by Jonathan Levin - more about frameworks, daemons, and launchd.

Everything else

 * "Has anyone looked into granting entitlements in iOS 8? It would appear the popular method of hooking "_XPCConnectionHasEntitlement" no longer works." "I haven't had a whole lot of time to do testing or look for better methods but I found "_BSAuditTokenTaskHasEntitlement" which appears to have a similar function to "_XPCConnectionHasEntitlement", it's part of the "assertiond" process which must be hooked in order to access it, so far it's worked. More specifically, part of the "BaseBoard" private framework within "assertiond"."


 * PLBatteryPropertiesEntry no longer seems to exist for getting current battery info such as: . You can still use:


 * PrivateFrameworks (and possibly others) in the iOS 8 SDK are missing the __TEXT section. Frameworks must be extracted from a device's dyld_shared_cache using a tool like JTool or IDA before they can be (statically) reverse engineered. See dyld_shared_cache for more info.


 * Many functions from SBMediaController have been removed, and it is now useless for accessing now playing information.  and   can be utilized for displaying track time. Use MediaRemotes   on the local notification center for updates when now playing info changes. You can also use   for updates on the playback state. Use   to access now playing info. This code works fine on iOS 7 and 8.


 * You can no longer mount FAT-formatted storage devices via the CCK, only HFS.


 * "Has anyone figured out how to add subviews to UIAlertView in iOS 8 yet?" "I found a workaround so I can at least add to the content view (which is not the size of the full alert view though). Within a subclass of UIAlertView do . When not subclassing,   should work, although one has to figure out the right time to do that."

Using posix_spawn to kill the camera app would work like this:
 * system is now deprecated. Apple recommends using posix_spawn instead.

Technically you can allow the use of system by wrapping it like so:

Alternatively you can make a wrapper function if you use system a lot in your code:

However that is not recommended. Instead of just replacing system("kill ..."), you should find the pid of the process you are trying to kill and send it a kill signal.


 * When a passcode is set, normal UIWindows are not rendered when on the lockscreen, although touch events are still received. You can make your own UIWindows show up over the lockscreen by calling, or you can override   in UIWindow to always return YES for all new UIWindows. (CAContext has a new property   which controls this behaviour.)


 * CoreMedia's FigVibratorPlayVibrationWithDictionary in iOS8 requires new parameters. Research of limneos and moeseth found out this

where d is a dictionary of ID which includes ClientPID, ClientPort, SSID and UserID.

= What is new in iOS 8, and how does it work? =


 * The view Reachability invokes is in the new framework FrontBoard - you can hook it. It is a FBWindowContextHostView. To toggle it:


 * To support Reachability on smaller devices, hook SBReachabilityManager class's


 * FrontBoard is a new framework that takes up a few of BackBoardServices' responsibilities. SpringBoard now inherits from FBSystemApp, which in turn is a UIApplication subclass.


 * CameraKit is a new framework that takes everything related to the camera out of PhotoLibrary.framework. PLCameraController is now the humungous CAMCaptureController.


 * Apple seems to call the iOS side Octavia and the OS X side Nero

= Which tools and other preexisting things are still working on iOS 8? Which ones don't work? =


 * Activator, Flipswitch and AppList updates compatible with iOS 8 are live on BigBoss repository (verified by rpetrich).


 * The package  has been updated for iOS 8, as of November 9. There are alternatives listed on System Log if you want to use a different method of accessing syslog though.


 * "Does Theos work on iOS 8?" uroboro responds here
 * However, theos may spit out a lot of errors about "Unsupported architecture", when using the iOS 8.1 SDK. These can safely be ignored.


 * libstatusbar is compatible with iOS 8 as of version 0.9.8.


 * libsymbolicate is compatible with iOS 8 as of version 1.8.0.


 * "RocketBootstrap seems to work." - it works perfectly with my tweak [Simon Selg]. Maybe not working as well with Flex though?


 * "What works for dumping classes on iOS 8? classdumpz doesn't seem to work. I'm trying to dump them directly on an iPhone 6." "You could use class-dump for i386 and the iOS 8 simulator" "This class-dump works for me." "If you want to dump on your iPhone then just compile its source to ARM; IIRC its distributed binary is x86/64 only."


 * "Does weak_classdump_bundle fail for anyone else on SpringBoard?" "It fails in general, it needs to be updated. You can dump SpringBoard with classdump-dyld." An updated classdump-dyld (that supports 64bit executables dumping) is available on GitHub and on BigBoss (changelog).

= Random assorted other notes =


 * iOS 8.0 Headers, another set of SpringBoard headers, another set of SpringBoard headers Part-1 and another set of SpringBoard headers Part-2 (made with different class dumping tools).


 * In things like SBStarkBanner* classes, Stark is the codename for CarPlay™ since iOS 7