iOS save picture to album crashes

Project iterative development process, there are users to reflect the save picture to the album Crash, and finally self-test, in the iOS11 below the normal storage, and iOS11 after the mobile phone will appear to reflect the problem. The print error message is as follows:

This app has crashed because it attempted to access privacy-sensitive data without a usage description. The app‘s Info.plist must contain an NSPhotoLibraryAddUsageDescription key with a string value explaining to the user how the app uses this data.

Google Translate:

This application has crashed because it tries to access privacy sensitive data without the use of instructions. The info.plist of an application must contain a Nsphotolibraryaddusagedescription key, in which the string value explains to the user how the application uses this data.

Access to the data, the cause of the problem is the IOS11 system after the new Apple added a permission to save the image later need to add permission "Privacy-photo Library additions Usage Description".

After testing, for the device not upgraded to iOS11 save the picture and no problem, but the device upgrade to IOS11 and then save the picture app will definitely crash, so quickly add to Info.plist file.

iOS save picture to album crashes