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.