ios - Objective C- Import error with singleton -

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• circular import issues in objective c & cocoa touch 2 answers

i quite new on objective c please bit slow me.

i have constructed views this: viewcontroller=>root(view)=>controls(view). root singleton can root element of app time.

when add #import "root.h" controls.h parse issue.

#import <uikit/uikit.h> #import "root.h"      // triggers error  @interface controls : uiview  @end 

here root.h

#import <uikit/uikit.h> #import <foundation/foundation.h> #import "controls.h" #import "content.h"  @interface root : uiview {     controls *m_controls; // parse error: unknown type name "controls" } +(root*)getinstance; @end 

what causes that? how fix?

you use #import *.h in *.m file, when need use class in *.h use @class.

so, must change class this:

#import <uikit/uikit.h> @class root  @interface controls : uiview @end 

and in *.m file:

#import "root.h"