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TJ Rogers
TJ Rogers
8,758 Points

Error in one of the Tut Vids?

First, let me start off with an observation: Amit is awesome. I've really been enjoying the iOS course, and have learned a lot so far.

But I've sort of hit a wall in understanding the getter/setter principle in properties, and I'm hoping this is because there is a small error in the video - otherwise, I'll just need to watch it another five or ten times, after which I'm sure it will click.

In the "Understanding @Property" video (in the "Refactoring into a Model" section of "Build a Simple iPhone App"), at the 1:02 mark, the getter method for:

@property(strong, nonatomic) NSArray *predictions;

is declared as:

  • (NSString *) predictions;

Should this rather be:

  • (NSArray *) predictions;

I certainly hope this is the answer, because I've spent a lot more time than I care to admit trying to figure out how NSString works as a getter method for an NSArray property.

Apologies if this seems like a dumb or obvious question, but before a few weeks ago I had never even laid eyes on a block of code, let alone attempted to understand or write it myself. So I'm REALLY new at all this.

3 Answers

Amit Bijlani
Amit Bijlani
Treehouse Guest Teacher

You are right! Thanks for pointing it out. We will have our video team fix it. You sir have a keen eye for details :)

Stone Preston
Stone Preston
42,016 Points

it looks like you are right. If its getting the array of predictions, its return type should be NSArray *. Looks like there is a typo in that graphic thats used in the video.

TJ Rogers
TJ Rogers
8,758 Points

Phew! I understand @property now.