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    <p>First, </p> <blockquote> <p>"how to pass the correct managed object context down to my custom NSManagedObjects."</p> </blockquote> <p>We create <code>NSManagedObject</code> with <code>NSManagedObjectContext</code>. not the other way around. So, when you have a <code>NSManagedObject</code>, you can access the <code>NSManagedObjectContext</code> by asking its property: <code>– managedObjectContext</code> as listed in <a href="https://developer.apple.com/library/mac/#documentation/Cocoa/Reference/CoreDataFramework/Classes/NSManagedObject_Class/Reference/NSManagedObject.html" rel="nofollow"><strong>Apple Document</strong></a> </p> <p>Second,</p> <p>When working with CoreData, multi-threading could be a little tricky. especially for the beginner. The are all kind of details that you need to take care of. </p> <p>I highly recommend you checkout the <code>Parent-Child NSManagedContext</code>. then, using <a href="https://github.com/magicalpanda/MagicalRecord" rel="nofollow"><strong>MagicRecord</strong></a>.</p> <p>By using <a href="https://github.com/magicalpanda/MagicalRecord" rel="nofollow"><strong>MagicRecord</strong></a>, you can simply Grand Central Dispatch with a Block like this:</p> <pre><code>[MagicalRecord saveInBackgroundWithBlock:^(NSManagedObjectContext *localContext){ // here use the `localContext` as your NSManagedContext and do things in the background. // it will take care of all the rest. }]; </code></pre> <p>If you need to pass <code>NSManagedObject</code> into this block, remember to only pass the <code>NSManagedObjectID</code> instead of the proprety.</p> <p>this is a example.</p> <pre><code>NSManagedObjectID *coaMapID = CoaMap.objectID; [MagicalRecord saveInBackgroundWithBlock:^(NSManagedObjectContext *localContext){ coaMap *aCoaMap = (coaMap *)[localContext existingObjectWithID:coaMapID error:&amp;error]; // then use aCoaMap normally. }]; </code></pre> <p>Hope this helped.</p>
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    1. POCore Data & GCD: Passing the correct managed object context to custom NSManagedObjects
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    1. USKyle Fang
    1. USKyle Fang
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    1. COKyle, what is the advantage of using MagicalRecord's `saveInBackgroundWithBlock` vs `[context performBlock...]` with `NSPrivateQueueConcurrencyType` introduced in iOS 5?
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    2. COthe awesome advantage is that you don't need the `NSPrivateQueueConcurrencyType`, the `BackgroundThread`, the `performBlock` and the `save` and so much more. It does it all. let you focus what you really need to do.
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