Concurrency with Core Data

Threading is a complex problem in applications. Adding Core Data to the mix doesn't make it easier. However, if you follow some rules you can perform Core Data operations on Background queues without too much trouble.

Transcript

1. Background Saving
   with Core Data
   Josh Johnson
   josh@twotoasters.com
   twitter.com/jnjosh
   Sunday, December 4, 11
   

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2. Concurrency with
   Core Data
   Josh Johnson
   josh@twotoasters.com
   twitter.com/jnjosh
   Sunday, December 4, 11
   

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3. “Why support
   concurrency?”
   Sunday, December 4, 11
   

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4. http://skitch.com/okidokie/nm31y/beach-ball-mac-osx
   Sunday, December 4, 11
   

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5. Wait... Isn’t this too
   hard?
   Sunday, December 4, 11
   

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6. Wait... Isn’t this too
   hard?
   http://www.wallchan.com/sandbox/57897/
   Sunday, December 4, 11
   

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7. http://kelvinslush.com/blog/the-rules
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8. Thread Confinement
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9. NSManagedObjectContext
   NSManagedObject
   Rule 1.
   &
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10. NSManagedObjectContext
    NSManagedObject
    Rule 1.
    &
    Not Thread-safe
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11. NSManagedObjectId
    Rule 2.
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12. NSManagedObjectId
    Rule 2.
    Is Thread-safe
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13. NSManagedObjectId
    Rule 2.
    Is Thread-safe
    [otherMoc objectWithID:objectID]
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14. Merge Changes from
    Notifications
    Rule 3.
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15. Merge Changes from
    Notifications
    Rule 3.
    NSManagedObjectContextDidSaveNotification
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16. Merge Changes from
    Notifications
    Rule 3.
    NSManagedObjectContextDidSaveNotification
    [moc mergeChangesFromContextDidSaveNotification:note];
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17. No Thread
    Confinement?
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18. http://63angel.blogspot.com/2011/07/danger-will-robinson-obsessions.html
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19. http://pennystockgurus.blogspot.com/2010_07_01_archive.html
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20. “Siri, make my app
    better”
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21. http://skitch.com/okidokie/nm31y/beach-ball-mac-osx
    Demo
    NSOperation
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22. Wait... Isn’t this too
    hard?
    http://www.wallchan.com/sandbox/57897/
    Sunday, December 4, 11
    

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23. GCD & Blocks
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24. Grand Central Dispatch
    & Blocks
    Concurrent And Asynchronous Programming With GCD
    Nathan Eror
    Saturday @ 2:45pm
    Sunday, December 4, 11
    

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25. “The irresponsibly quick
    review”
    Grand Central Dispatch
    & Blocks
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26. Blocks
    http://developer.apple.com/library/ios/#documentation/cocoa/Conceptual/Blocks/Articles/00_Introduction.html
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27. GCD
    dispatch_async(dispatch_get_main_queue(), ^{
    [self doSomethingImportantOnMainQueue];
    });
    dispatch_async(myQueue, ^{
    [self doSomethingImportant];
    });
    Sunday, December 4, 11
    

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28. Grand Central Dispatch
    & Blocks
    Concurrent And Asynchronous Programming With GCD
    Nathan Eror
    Saturday @ 2:45pm
    Sunday, December 4, 11
    

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29. http://skitch.com/okidokie/nm31y/beach-ball-mac-osx
    Demo
    GCD & Blocks
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30. Sunday, December 4, 11
    

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31. Core Data Concurrency in iOS 5
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32. Core Data Concurrency in iOS 5
    • Concurrency Types
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33. Core Data Concurrency in iOS 5
    • Concurrency Types
    • NSConfinementConcurrencyType
    • NSMainQueueConcurrencyType
    • NSPrivateQueueConcurrencyType
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34. Core Data Concurrency in iOS 5
    • Concurrency Types
    • NSConfinementConcurrencyType
    • NSMainQueueConcurrencyType
    • NSPrivateQueueConcurrencyType
    • Parent / Child Contexts
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35. http://skitch.com/okidokie/nm31y/beach-ball-mac-osx
    Demo
    Parent / Child Contexts
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36. Resources
    MAGICALRECORD
    https://github.com/magicalpanda/MagicalRecord
     http://developer.apple.com
    http://cimgf.com
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37. Questions?
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38. Thank You!
    Josh Johnson
    josh@twotoasters.com
    twitter.com/jnjosh
    Sunday, December 4, 11
    

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