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iOS Objective-C Basics (Retired) Foundation Framework NSDictionary

Posted by Pedro Lima
Pedro Lima
659 Points

Challenge 3 of NSDictionary

My bad, I am stuck again. [albumMutable setObject:@1969 forKey:@"year"]; I rechecked my work various times for silly mistakes, but this is the only way the video taught us how to do it.

1 Answer

Mike Baxter
Mike Baxter
4,442 Points
Mike Baxter
Mike Baxter
4,442 Points

Watch the quotation marks around NSString literals. Should be @"1969". A literal is any Objective-C class you don't specifically allocate but create in-line, such as NSString, NSArray, NSDictionary. You can make all of them explicitly with the alloc->init paradigm, or save yourself time and do the literals. But if you do them as literals, you have to be careful to get the syntax right.

Here's a good list of the syntax for the literals:

http://cocoaheads.tumblr.com/post/17757846453/objective-c-literals-for-nsdictionary-nsarray-and