问题
I originally downloaded the FBSDK's version 4.10 and integrated them into my application by placing them in the frameworks folder. Realizing that these would not get updated over time, I removed them completely and tried to add them as pods to my project. The pods installed successfully, I have imported them correctly in my bridging header file, and there were no other issues. The pods update installed version 4.11 which has caused me some headache.
I am using the FBSDKLoginKit to log a user into their account and retrieve information from that. I am able to get back a dictionary with the users information just fine. I then pass this information to the next ViewController with a segue. At any point after this, if I press the home button on my iPhone or simulator, the app will crash. The error I get is
*** Terminating app due to uncaught exception 'NSInvalidArgumentException',
reason: '*** -[__NSPlaceholderDictionary initWithObjects:forKeys:count:]:
attempt to insert nil object from objects[3]'
This exception also occurs if I let the user log in through facebook, segue to the new view controller, unwind to the previous view controller, and then attempt to log in again. I have attempted to log the user out once retrieving their pertinent information on the second screen, but the error still persists.
I have seen a similar question asked where the "solution" was that the FBSDKLoginKit writes the retrieved dictionary to a variable and if the dictionary it has retrieved back has nil values, it throws this error.
Is there anything I can do to catch this before it happens? Has anyone found a work around?
Here is my output from the simulator when I press home:
*** First throw call stack:
(
0 CoreFoundation 0x0000000106f03d85 __exceptionPreprocess + 165
1 libobjc.A.dylib 0x000000010643edeb objc_exception_throw + 48
2 CoreFoundation 0x0000000106e0023e -[__NSPlaceholderDictionary initWithObjects:forKeys:count:] + 318
3 CoreFoundation 0x0000000106e125bb +[NSDictionary dictionaryWithObjects:forKeys:count:] + 59
4 APPNAME 0x0000000101607a1e -[FBSDKTimeSpentData instanceSuspend] + 622
5 APPNAME 0x000000010160766b +[FBSDKTimeSpentData suspend] + 59
6 APPNAME 0x00000001015b5986 -[FBSDKAppEvents applicationMovingFromActiveStateOrTerminating] + 262
7 CoreFoundation 0x0000000106ecdc8c __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 12
8 CoreFoundation 0x0000000106ecd9cb _CFXRegistrationPost + 427
9 CoreFoundation 0x0000000106ecd732 ___CFXNotificationPost_block_invoke + 50
10 CoreFoundation 0x0000000106f161e2 -[_CFXNotificationRegistrar find:object:observer:enumerator:] + 1986
11 CoreFoundation 0x0000000106dc5679 _CFXNotificationPost + 633
12 Foundation 0x000000010372ccd9 -[NSNotificationCenter postNotificationName:object:userInfo:] + 66
13 UIKit 0x0000000104a685ad -[UIApplication _deactivateForReason:notify:] + 629
14 UIKit 0x0000000104a6f1f1 __61-[UIApplication _sceneSettingsPreLifecycleEventDiffInspector]_block_invoke + 104
15 FrontBoardServices 0x0000000108f88d6c __52-[FBSSettingsDiffInspector inspectDiff:withContext:]_block_invoke27 + 213
16 Foundation 0x000000010377d5bb __NSIndexSetEnumerate + 1016
17 BaseBoard 0x000000010901ba8c -[BSSettingsDiff inspectChangesWithBlock:] + 116
18 FrontBoardServices 0x0000000108f83e4a -[FBSSettingsDiff inspectOtherChangesWithBlock:] + 92
19 FrontBoardServices 0x0000000108f88b2f -[FBSSettingsDiffInspector inspectDiff:withContext:] + 317
20 UIKit 0x0000000104a70880 __70-[UIApplication scene:didUpdateWithDiff:transitionContext:completion:]_block_invoke + 127
21 UIKit 0x0000000104a7052d -[UIApplication scene:didUpdateWithDiff:transitionContext:completion:] + 843
22 FrontBoardServices 0x0000000108f978c8 __FBSSERIALQUEUE_IS_CALLING_OUT_TO_A_BLOCK__ + 24
23 FrontBoardServices 0x0000000108f97741 -[FBSSerialQueue _performNext] + 178
24 FrontBoardServices 0x0000000108f97aca -[FBSSerialQueue _performNextFromRunLoopSource] + 45
25 CoreFoundation 0x0000000106e29301 __CFRUNLOOP_IS_CALLING_OUT_TO_A_SOURCE0_PERFORM_FUNCTION__ + 17
26 CoreFoundation 0x0000000106e1f22c __CFRunLoopDoSources0 + 556
27 CoreFoundation 0x0000000106e1e6e3 __CFRunLoopRun + 867
28 CoreFoundation 0x0000000106e1e0f8 CFRunLoopRunSpecific + 488
29 GraphicsServices 0x0000000108ae7ad2 GSEventRunModal + 161
30 UIKit 0x0000000104a72f09 UIApplicationMain + 171
31 APPNAME 0x00000001013a26d2 main + 114
32 libdyld.dylib 0x0000000107b0d92d start + 1
33 ??? 0x0000000000000001 0x0 + 1
) libc++abi.dylib: terminating with uncaught exception of type NSException
Running my code step by step I find that the error occurs during the method:
fbLoginManager.logInWithReadPermissions(permissionsNeeded, fromViewController: self) { (result, error) -> Void in
//crashes before it enters this block
//my code here
}
It crashes before I can even check the error value. I will attempt to check the values by stepping into the fbsdk methods and update
As soon as I press OK on this screen for the second time it crashes. How can I debug this? The action isn't in my app, its in the browser so I'm not sure where to go from here..
回答1:
I have came across this issues recently, and i solved it by adding this piece of code in Appdelegate.m.
- (void)applicationDidBecomeActive:(UIApplication *)application {
[FBSDKAppEvents activateApp];
}
For Swift 3 version:
func applicationDidBecomeActive(_ application: UIApplication) {
FBSDKAppEvents.activateApp()
}
回答2:
Update to 4.12, it fixes the issue according to their release notes:
https://developers.facebook.com/docs/ios/change-log-4.x/
The part that says:
Fixed
- Fixed cases where AppEvents could crash because of missing session id.
- Fixed bug in some cases where access token expiration date was the refresh date.
回答3:
Although this is not necessarily a comprehensive solution, I have exhausted my debugging methods. I have removed the FBSDK's from my podfile, run pod update to remove them from the project, and reinstalled the version 4.10 FBSDK's in my frameworks folder. I will update this question after trying again when facebook releases an updated version of the FBSDK's.
来源：https://stackoverflow.com/questions/36660952/app-crashes-using-facebook-login-sdk-when-i-go-to-the-home-screen