CoreData error with EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)
来源： https://stackoverflow.com/questions/40500684/coredata-error-with-exc-bad-instruction-code-exc-i386-invop-subcode-0x0
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CoreData error with EXC_BAD_INSTRUCTION (code=EXC_I386_INVOP, subcode=0x0)
来源： https://stackoverflow.com/questions/40500684/coredata-error-with-exc-bad-instruction-code-exc-i386-invop-subcode-0x0
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managedObjectModel is nil (Cannot create an NSPersistentStoreCoordinator with a nil model)
I have this special case scenario, where in my app works perfectly fine for some time and crashes inconsistently after some time. The error that i get during the crash is "Cannot create an NSPersistentStoreCoordinator with a nil model" . I tried debugging my app and found that the managedObjectModel is returning NULL sometimes. To add fuel to the fire, this scenario is not at all consistent. For some time the managedObjectModel is fine. But, suddenly it returns NULL ... Here is the code that I am using to create a managed object model. - (NSManagedObjectModel *)managedObjectModel { if
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I am looking for either a sample app or a more architectural discussion to build an app, which maintains a local persistent store (CoreData) and keeps it sync against a Web-Service like Flickr. In my case it is Salesforce, but the pattern should be similar to many apps for Flickr, Twitter, IMAP and so on. Sample questions: where are the best points to invoke the syncing? what are proven datastructures to maintain local changes - maintain a "changed" BOOL in the local store for every unsynched change; I would prefer a field level flag against a record level flag)? Of course I have to optimize
Why does Core Data initialization fail when I attempt to do it at these points?
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