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iOS Objective-C Basics (Retired) Introduction to Objective-C Syntax Overview

Posted by Ruth Hedley
Ruth Hedley
1,972 Points

setCenterAndRadius

At 1:47 the narration talks about creating a function setCenterAnd Radius but actually types setCenter (which we have already defined). Is this a typo?

2 Answers

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

if you continue watching you will see he adds a second radius parameter to the method so it looks like this:

- (void)setCenter:(NSArrray *)center radius:(float)radius;

thus, you now have a method that sets the center and the radius. this method is different from your setCenter method, which only takes one argument and is named setCenter, whereas this one takes 2 arguments and is named setCenter radius

objective c methods are read from left to right like usual (but you only read the words that come before the colons), so if you wanted it to literally be read as setCenter andRadius you would need to use the following definition:

- (void)setCenter:(NSArrray *)center andRadius:(float)radius;
Ruth Hedley
Ruth Hedley
1,972 Points

Thanks for the quick response! I incorrectly assumed that a method name only had one part to it.

Sungbae Park
Sungbae Park
9,389 Points
Sungbae Park
Sungbae Park
9,389 Points

Why does Douglass not explain this...my word