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POAccessing a core data NSManagedObject after resuming from background crashes the app
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  1. POAccessing a core data NSManagedObject after resuming from background crashes the app
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    copied!<p>I'm using core data and have found the app sometimes crashing after resuming from background. I've identified the crash occurring inside a block method body when I try to access a property on a <code>NSManagedObject</code> subclass. </p> <p>I have a property which holds a reference to a <code>NSManagedObject</code> subclass. </p> <blockquote> <p>@property(nonatomic,strong) CalItem *calObject;</p> </blockquote> <p>To reproduce the crash I first need to call the child viewController(<code>NoteViewController</code>) passing a block (<code>NoteTextBlock</code>).</p> <pre><code>NoteViewController *noteViewController = [[NoteViewController alloc]initWithNote:self.calObject.note NoteTextBlock:^(NSString *noteText) { self.calObject.note = noteText; //crashing here }]; </code></pre> <p>Then send the app to background and resume it. Afterwards in the NoteViewController I'll return a message to the calling viewController.</p> <pre><code>if (self.noteTextBlock) { self.noteTextBlock(trimmedString); } </code></pre> <p>When the block returns and the line <code>self.calObject.note = noteText</code> gets executed the app crashes.</p> <p>So apparently you can't put a block on the stack, quite and resume the app and then continue with what was defined inside the block ? Or am I just doing something wrong here ?</p> <p><strong>Edit:</strong><br> <code>*** Terminating app due to uncaught exception 'NSObjectInaccessibleException', reason: 'CoreData could not fulfill a fault for '0xb253100 &lt;x-coredata://C2304B7C-7D51-4453-9993-D33B9113A7A5/DTODay/p57&gt;''</code></p> <p>The block is defined like this inside the child viewController:<br></p> <pre><code>@property(nonatomic, copy)NoteTextBlock noteTextBlock; </code></pre> <p><strong>Edit2</strong><br> This is what I get when I set a breakpoint on the line where it crashes.<br> <code>(lldb) po self.calObject</code><br> <code>$2 = 0x0b4464d0 &lt;DTODay: 0xb4464d0&gt; (entity: DTODay; id: 0xb489d00 &lt;x-coredata://C2304B7C-7D51-4453-9993-D33B9113A7A5/DTODay/p57&gt; ; data: &lt;fault&gt;)</code></p> <p>I'm using the MagicalRecord lib to manage all the Core Data stuff.</p> <pre><code>- (void)applicationDidBecomeActive:(UIApplication *)application { if ([NSManagedObjectContext MR_defaultContext] == nil || [NSManagedObjectModel MR_defaultManagedObjectModel] == nil || [NSPersistentStoreCoordinator MR_defaultStoreCoordinator] == nil || [NSPersistentStore MR_defaultPersistentStore] == nil ) { //coming back from background, re-init coredata stack [MagicalRecordHelpers setupCoreDataStackWithAutoMigratingSqliteStoreNamed:DBNAME]; } </code></pre>
 

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