xcode - iOS compile error: No visible @interface for 'CDViewController' declares the selector -

since switched ios project arc, keep getting compiler error:

no visible @interface 'cdviewcontroller' declares selector 'setuseagof:'

in line:

[self.viewcontroller setuseagof:false]; 

in file:

appdelegate.m

#import "appdelegate.h" #import "mainviewcontroller.h" #import <cordova/cdvplugin.h> #import "nsstring+md5.h"  @implementation appdelegate  @synthesize window, viewcontroller;  - (bool)application:(uiapplication*)application didfinishlaunchingwithoptions:(nsdictionary*)launchoptions {     // (...)     [self.viewcontroller setuseagof:false]; // <-- here     // (...)      return yes; }  @end 

although method defined:

mainviewcontroller.h

#import <cordova/cdvviewcontroller.h> #import <adtechmobilesdk/adtechmobilesdk.h>  @interface mainviewcontroller : cdvviewcontroller <atinterstitialviewdelegate>{     atinterstitialview *interstitial; } - (void)setuseagof:(bool)useagofparam; @end  @interface maincommanddelegate : cdvcommanddelegateimpl @end  @interface maincommandqueue : cdvcommandqueue @end 

mainviewcontroller.m

#import "mainviewcontroller.h"  @interface mainviewcontroller()     - (void)setuseagof:(bool)useagofparam; @end  @implementation mainviewcontroller  bool useagof = true;  - (void)setuseagof:(bool)useagofparam {     nslog(@"1.) setting useagof = %d", (int)useagofparam);     useagof = useagofparam; } 

i don't it. what's wrong?

---

update:

appdelegate.h

#import <uikit/uikit.h> #import <cordova/cdvviewcontroller.h> #import <infonlinelibrary/infonlinelibrary.h>  @interface appdelegate : nsobject <uiapplicationdelegate>{}  @property (nonatomic, strong) iboutlet uiwindow* window; @property (nonatomic, strong) iboutlet cdvviewcontroller* viewcontroller;  @end 

viewcontroller seems declared pointer of cdvviewcontroller. calling method part of mainviewcontroller class derived cdvviewcontroller. method being called part of derived class , not base class, hence make viewcontroller pointer of mainviewcontroller instead.