Objective c - Iad WARNING: More than 10 instances of ADBannerView

问题

i have developed a tab bar application. Like title i have an iad banner positioned at bottom of screen. I have implemented this method to create/destroy banner and test iad works correctly:

Create:

-(void)viewWillAppear:(BOOL)animated {
     if(!adView) {
        adView = [[ADBannerView alloc] initWithFrame:CGRectMake(0, 315, 310, 45)];
        adView.requiredContentSizeIdentifiers = [NSSet setWithObject:ADBannerContentSizeIdentifierPortrait];
        adView.currentContentSizeIdentifier = ADBannerContentSizeIdentifierPortrait;
        adView.delegate = self;
        [self.view addSubview:adView];
    }

Destroy:

    - (void)viewWillDisappear:(BOOL)animated {
    [super viewWillDisappear:animated];

    // iAd
    if (adView != nil) {
        adView.delegate = nil;
        adView.hidden = YES;
        adView = nil;
       [adView release];
    }  
}

But if i try to rapid change view from tab bar i receive this error:

WARNING: More than 10 instances of ADBannerView or ADInterstitialView currently exist. This is a misuse of the iAd API, and ad performance will suffer as a result. This message is printed only once.

But the method create and destroy are always called. What i can do to debug this warning problem? Thanks so much.

回答1:

You need to release your instance variable before you nil it, not the other way around.

adView = nil;
[adView release];

Should be:

[adView release];
adView = nil;

来源：https://stackoverflow.com/questions/12669989/objective-c-iad-warning-more-than-10-instances-of-adbannerview