ios - iAd Banner Notification? -

i'm using following code setup vc can display banner ads

[self setcandisplaybannerads:yes]; 

the problem i'm having display text @ bottom of application unless of course banner ad appears in case place text on top of banner. can't seem find delegate method called or other way make happen using setcandisplaybannerads. missing simple here?

iad banner has 2 delegate methods notifies observer whether iad banner available display or not. these delegate methods are:

#import <uikit/uikit.h> #import <iad/iad.h>  @interface viewcontroller : uiviewcontroller<adbannerviewdelegate>  - (void)bannerviewdidloadad:(adbannerview *)banner {     if (!_bannerisvisible)     {         _bannerisvisible = yes;     } }  - (void)bannerview:(adbannerview *)banner didfailtoreceiveadwitherror:(nserror *)error {     _bannerisvisible = no; } @end 

with _bannerisvisible bool variable can decide when show text there or not.