We try to keep our books accurate, but sometimes mistakes creep in. This page lists the errors submitted by our astute readers. If you've found a new error, please submit it.

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Key: Typo Tech. Error Suggestion Not a problem Next edition

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PDF Paper Description Found in Fixed in
1
#76322: In the extract (no page numbers, so I entered "1"), under: 6.1 Introducing the UIManagedDocument, Manually Saving a UIManagedDocument, I f...more...
P1.0
21-Jan-14
3,10
#53055: Sec 1.4 The interface property for "serves" should be a NSUInteger type instead of an NSString. This would be consistent with the CD model p...more...
P1.0
21-Oct-13
9
#51137: NSManagedObjectContext ... Therefor, we hand off the reference to it to our AppDelegate so the the rest of the application can access it. T...more...
P1.0
26-Mar-13
18/26
#50484: I've been unable to run the sample code because of the lack of initialization of the data base. I could not find a section of the book or note...more...
B4.0
18-Jan-13
20

#53039: The screenshot shows a highlighted fetch request name "bigMeals". The code snippet below it calls for "allIngredients".--Bruce Payan

P1.0
20-Oct-13
20
#51451: Under the section on StoreFetchedRequests, the code snippet includes an example of using NSSortDescriptors, which are not covered until the ne...more...
P1.0
05-May-13
26
#53036: In the section on wiring up the UITableView ("Wiring the NSFetchedResultsController to a UITableView"), the data source protocol is referred t...more...
P1.0
18-Oct-13
28 14
#50847: In Chapter 1. Under the Hood of Core Data, subsection Property Accessors there is a wrong reference in the following text: --- Relations...more...
P1.0
24-Feb-13
29
#50503: These two lines are not correct: NSArray *newArray = [NSArray arrayWithObject:newIndexPath]; NSArray *oldArray = [NSArray arrayWithObject:...more...
B4.0
21-Jan-13
29
#50626: [REF: Pete Hopkins B4 Note] Within the first printing the tech. error noted by Pete Hopkins in B4 still remains. NSArray *newArray = [NS...more...
P1.0
31-Jan-13
34
#50838: finalPredicate never declared either in the class or within the local method scope. You might want to check the code being posted on media.pra...more...
P1.0
19-Feb-13
34
#76477: In the code snippet you define NSPredicate *final; but then go on and use an undefined predicate called finalPredicate. - (void)addEntityT...more...
P1.0
04-Mar-14
35
#51654: (Or a suggestion) 1) The results mDictionary is local to -contextUpdated and never assigned/passed so how does it "...pass the newly created...more...
P1.0
28-May-13
39
#50502: The creation of the UIAlertView is done within the dispatch_async block on the global queue, which causes an error. It should be done on a blo...more...
B4.0
21-Jan-13
39

#76713: The `UIAlertView` is created and displayed from a background thread.--Incorrect UI thread

P2.0
21-Apr-14
43

#50774: Screen shots of data models are equal, screen shot for version 2 is missing the Author entity and the lastUsed property.

P1.0
08-Feb-13
47

#51476: "NSEntityMigrationPolicy is designed to be subclasses..."

"Subclasses" should be "subclassed".--Zachary Klein

P1.0
08-May-13
63
#76288: Figure 13 is named "Turn on the external record flag," which suggests the Spotlight flag. Combined with the previously-noted fact that the fig...more...
P1.0
13-Jan-14
63
#51523: 5th Paragraph. Text mentions to "turn on external binary storage," however the corresponding image referenced (figure 13, pg. 64) shows the "...more...
P1.0
15-May-13
67
#50486: In the book on page 67/336 in the code for ZSContextWatcher.m, the sample shows, NSPredicate *final = nil; Where in the Github copy of Z...more...
B4.0
19-Jan-13
82
#76286: Since this is all about getting the export off the main thread, adding the export operation to the mainQueue makes no sense. (The import code ...more...
P1.0
13-Jan-14
86
#52057: In the first code example on the page, this line is incorrect: [dict addEntriesFromDictionary:[self moToDictionary:childMO]]; It should re...more...
P1.0
24-Jun-13
86

#76287: If the lastUsed attribute of the Recipe entity is set, JSON serialization will fail here, since NSDate isn't supported.--Randy Saldinger

P1.0
13-Jan-14
92
#51215: Book describes 5.5 Parent-Child NSManagedObjectContext Instances With the release of iOS 6.0 and Mac OS X 10.8 Mountain Lion, a number of ...more...
P1.0
03-Apr-13
95
#50481: [self setValue:childSet forKey:key]; This line of code is VERY likely not what's wanted here (it's broken). Calling setValue on "self" refe...more...
B4.0
17-Jan-13
211

#51005: At the bottom of the page it says "seques" instead of "segues".--koen

P1.0
11-Mar-13
219
#51548: Last line in the page begins with "The seques of this UIViewController." It should be "The segues of this UIViewController." (i.e. segues i...more...
P1.0
20-May-13
221
#52430: Reading ePub version, so page number won't work. Chapter 3.5, last paragraph: “Is it of vital importance…" I think it should be: "It is of ...more...
P1.0
20-Aug-13
229 222
#52058: I'm using Xcode 4.6.2. I'm having problems with your nifty Macros. Note: I have actually manually typed in the Macros (you provide in Append...more...
P1.0
24-Jun-13