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Kathleen Bryan
1,581 PointsCode won't run, no known class method for selector alloc?
I'm using a newer version of X-Code then the tutorial. In the tutorial the .m and .h made was under Iphone, Cocoa, Objective C class, since I did not have that option in my menu I selected the next closest thing which was Cocoa Class with objective C as the language.
In the first Objective C tutorial the typed out code in the main looked like:
Sphere *ball=[[Sphere alloc] init];
My code isn't running and says the error is "No known class method for selector 'alloc'"
How can I get this code to run and am I creating the correct kind of .m and .h
(I've checked the rest of my code for errors)
7 Answers
Michael Liendo
15,326 PointsHi there and welcome :)
Is there a reason you're using an older version of Xcode? If you're building an iPhone app, then you should be using the CocoaTouch framework and not Cocoa. Hope that helps, let me know if you need more assistance.
Michael Liendo
15,326 PointsOh I see, sorry for the mix up on the Xcode version. I'll look into it for you, what is the exact tutorial that you're on?
Kathleen Bryan
1,581 Pointshttp://teamtreehouse.com/library/objectivec-basics/introduction-to-objectivec/introducing-property
its introduction to the @property.
Thank you so much!
Michael Liendo
15,326 Pointshmmm...it worked for me. "no known class method.." essentially means that Xcode isn't recognizing your alloc method. In your .h file, have you made sure to subclass NSObject by putting Sphere: NSObject there? I'll attach my screenshots to make sure we're on the same page. Sorry for the long troubleshoot...I've been purely Swift for the past 7 months!
Michael Liendo
15,326 PointsWell I couldn't find an easy way to add photos :/ so I posted them on twitter for you :)
Kathleen Bryan
1,581 Pointsthanks so much I got it all figured out!
Kathleen Bryan
1,581 Pointsthanks so much I got it all figured out!
Kathleen Bryan
1,581 PointsKathleen Bryan
1,581 PointsNo, I'm using the newer version of Xcode, the tutorial is using the older version. I don't think it would be beneficial for me to revert back to an older version.
The options were not the same in my window as that of the tutorial. I selected the only Cocoa option available (which was yes, the CocoaTouch framework) and selected the language as Objective C. Where as in the tutorial he selected the Cocoa class and there was no language option.