Why does this crash

gistfile1.cpp

+ (TLAdView *)adViewForTopLevelTab:(NSDictionary *)topLevelTab
                                frame:(CGRect)frame
                 parentViewController:(UIViewController *)parentViewController
{
    
    TLLog( @"BCWebAdView:adViewForTopLevelTab:frame:%@", NSStringFromRect(frame) );
    
	NSString *adViewClassName =  @"BCWebAdView";
	TLAdView *adView = nil;
	
    if ([adViewClassName isEqualToString: @"GlamAdView"]) {
        NSLog(@"Warning: Glam ads not supported in this version of TapLynx. Please contact [email protected] if you see this message.");
				return nil; 
	}
/*    
    adView = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    //[adView setFrame:CGRectMake(0.0f, 100.0f, 320.0f, 50.0f)];
    [adView setFrame:frame];
    adView.backgroundColor = [UIColor greenColor];
    adView.opaque = YES;
*/
    
	if ([adView isKindOfClass:NSClassFromString(@"MedialetsAdView")]) {
		
        NSLog(@"Warning: Medialets are not supported in this version of TapLynx. Please contact [email protected] if you see this message.");
        
	}
	return adView;
}

-(void) createButtonTLAdView{
    NSLog(@"createButtonTLAdView");
    adButton = [UIButton buttonWithType:UIButtonTypeRoundedRect];
    [adButton setFrame:CGRectMake(0.0f, 100.0f, 320.0f, 50.0f)];
    adButton.backgroundColor = [UIColor greenColor];
    adButton.opaque = YES;
    NSLog(@"thisbutton %@", adButton);
    [self addSubview:adButton];
    [self bringSubviewToFront:adButton];
    
}

- (id)initWithAd:(UIView *)anAd delegate:(id<TLAdViewDelegate>)aDelegate {
    [self createButtonTLAdView];
    
    if ( ! [super initWithFrame:anAd.frame] ) return nil;
    
    TLLog(@"--- initWithAd ---"); 
    [self setDelegate:aDelegate];
    
    [TLUtil setOrigin:anAd origin:CGPointMake(0.0f, 0.0f)];

    //[self setBackgroundColor:[UIColor blueColor]];//TODO: revert to clearColor
   // [self setBackgroundColor:[UIColor clearColor]];

    [anAd setBackgroundColor:[UIColor clearColor]];
    TLLog( @"TLAdView:initWithAd:setBackgroundColor:clearColor:self:%@ anAd:%@", self, anAd );
    
    if ([anAd isKindOfClass:[BCWebAdView class]]) {
        [TLUtil setHeight:self height:[BCWebAdView preferredHeightForAd:anAd]];
    }
    
    [self addSubview:anAd];
    [self setAdView:anAd];
    
    return self;
}