Can't compile code when working with CALayer

Question

For some reason I get linker errors when I try and use CALayer:

  "_OBJC_CLASS_$_CALayer", referenced from: 

I have imported the following headers:

#import <Foundation/Foundation.h> #import <UIKit/UIKit.h> #import <QuartzCore/QuartzCore.h> 

Code:

arrowImage = [[CALayer alloc] init]; 

Answer 1

Make sure you also add the QuartzCore framework to your target. Just importing the header isn't enough.

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