iAds bug？或者我做错了什么

Question

我已经在我的Sprite套件游戏中实现了iAds，一切正常，除了我每次点击横幅然后返回游戏2-3次，游戏冻结，我应该重启应用程序。

尝试让iAd正常运行3天。似乎没有解决方法。我认为这可能是iAds的错误。

Viecontroller.h

#import <UIKit/UIKit.h>
#import <SpriteKit/SpriteKit.h>
#import <iAd/iAd.h>

@interface ViewController : UIViewController<ADBannerViewDelegate>

@end

Viewcontroller.m

#import "ViewController.h"
#import "MyScene.h"

@interface ViewController ()
{
    BOOL _bannerIsVisible;
    ADBannerView *_adBanner;
}
@end

@implementation ViewController

- (void)viewWillLayoutSubviews
{
    [super viewWillLayoutSubviews];

    // Configure the view.
    SKView * skView = (SKView *)self.view;
    skView.showsFPS = YES;
    skView.showsNodeCount = YES;
    skView.multipleTouchEnabled = YES;

    if ( !skView.scene ) { 

        SKScene * scene = [MyScene sceneWithSize:skView.bounds.size];
        scene.scaleMode = SKSceneScaleModeAspectFill;

        [skView presentScene:scene];
    }
}

- (void)viewDidAppear:(BOOL)animated // IADS
{
    [super viewDidAppear:animated];

    _adBanner = [[ADBannerView alloc] initWithFrame:CGRectMake(self.view.frame.size.width / 2 - 160, self.view.frame.size.height, 320, 50)];
    _adBanner.delegate = self;
}

- (void)bannerViewDidLoadAd:(ADBannerView *)banner
{
    if (!_bannerIsVisible)
    {
        // If banner isn't part of view hierarchy, add it
        if (_adBanner.superview == nil)
        {
            [self.view addSubview:_adBanner];
        }

        [UIView beginAnimations:@"animateAdBannerOn" context:NULL];

        // Assumes the banner view is just off the bottom of the screen.
        banner.frame = CGRectOffset(banner.frame, 0, -banner.frame.size.height);

        [UIView commitAnimations];

        _bannerIsVisible = YES;
    }
}

- (void)bannerView:(ADBannerView *)banner didFailToReceiveAdWithError:(NSError *)error // IADS
{
    NSLog(@"Failed to retrieve ad");

    if (_bannerIsVisible)
    {
        [UIView beginAnimations:@"animateAdBannerOff" context:NULL];

        // Assumes the banner view is placed at the bottom of the screen.
        banner.frame = CGRectOffset(banner.frame, 0, banner.frame.size.height);

        [UIView commitAnimations];

        _bannerIsVisible = NO;
    }
}

@end