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  1. PO
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    <p>first off, can you explain what the purpose of doing the following is for: </p> <p>first you create a new context with a private concurrency type.</p> <pre><code>NSManagedObjectContext *context = [[NSManagedObjectContext alloc]initWithConcurrencyType:NSPrivateQueueConcurrencyType]; </code></pre> <p>Now you take that context and reassign it to something else?</p> <pre><code>context = [appDelegate managedObjectContext]; </code></pre> <p>Now the context that you are using is the one you defined in your appDelegate...</p> <p>Furthermore, assuming that the context defined in your appDelegate is correct, you are performing a fetch request in the context asynchronously. Then on the following lines you check for the results of that fetch without knowing whether or not the fetch request has been returned or not (since it is asynchronous). This explains why you see the results the second time since they have been fetched by then. A quick fix would be to sprinkle in some GCD into the context block like so:</p> <pre><code>[context performBlock:^{ NSError *error = nil; NSArray *fetchedObjects = [context executeFetchRequest:request error:&amp;error]; dispatch_async(dispatch_get_main_queue(),^{ _objects = fetchedObjects; if (_objects == nil) { _status.text = @"No matches"; } else { NSLog(@"data= %@", [_objects description]); NSManagedObject *matches = _objects[0]; _address.text = [matches valueForKey:@"address"]; _phone.text = [matches valueForKey:@"phone"]; _status.text = [NSString stringWithFormat: @"%d matches found", [_objects count]]; } }); }]; </code></pre> <p>I hope this helps?</p>
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    1. POCore data background fetch not working
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    1. USDaniel Galasko
    1. USDaniel Galasko
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    1. This table or related slice is empty.
    1. This table or related slice is empty.
    1. POCore data background fetch not working
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    1. COThis is not working, it shows the error where I assigned matches = _objects[0], the error is "variable is not assignable(missing _block type specifier).
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      1. PO
      1. USParas Gorasiya
    2. COMy apologies, I edited my answer and created a temporary variable to store the results of the fetch and then assign it to the instance variable in the main queue. Try it again, it works on the sample app I just wrote...
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      1. USDaniel Galasko
    3. COStill the problem is same. I am doing background fetching of data and displaying it to respective text fields. Here I am assigning first object after search operation if I find more than one object in fetched objects and assigning it to NSManagedObject matches but I am not able to do it. Thanks in advance...
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      1. USParas Gorasiya
 

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