Calayer subclass problem

I am creating calayer subclass for carousel view.

My subclass is

@interface Carousellayer : CALayer {

}

I get an error m开发者_JAVA百科essage in

Cannot find interface declaration for 'CALayer', superclass of 'Carousellayer' in Carousellayer.h

---

CALayer header files are not included by default, you need to import QuartzCore:

#import <QuartzCore/QuartzCore.h>

And also link your application with the corresponding framework.