仅在iOS 7上使用iAd崩溃 - 弱委托是糟糕的指针

Question

我遇到了一个奇怪的崩溃，iAd错误回调。这是我的崩溃日志：

Exception Type: EXC_BAD_ACCESS Code: KERN_INVALID_ADDRESS at 0x2281
0com.apple.main-thread Crashed
0    libobjc.A.dylib     objc_retain + 17
1    YouDoodle AdView.m line 265 -[AdContainerView requestGAD]
2    iAd     -[ADBannerView _forwardErrorToDelegate:] + 254
3    iAd     -[ADBannerView serverBannerViewDidFailToReceiveAdWithError:] + 178
4    iAd     -[ADAdSpace setServiceAdSpace:] + 472
5    CoreFoundation  __CFNOTIFICATIONCENTER_IS_CALLING_OUT_TO_AN_OBSERVER__ + 12
6    CoreFoundation  _CFXNotificationPost + 1718
7    Foundation  -[NSNotificationCenter postNotificationName:object:userInfo:] + 76
8    Foundation  -[NSNotificationCenter postNotificationName:object:] + 30
9    iAd     -[ADAdSheetProxy _adSheetConnectionLost] + 292
10 ...   libdispatch.dylib   _dispatch_call_block_and_release + 10
11   libdispatch.dylib   _dispatch_client_callout + 22
12   libdispatch.dylib   _dispatch_main_queue_callback_4CF$VARIANT$up + 274
13   CoreFoundation  __CFRUNLOOP_IS_SERVICING_THE_MAIN_DISPATCH_QUEUE__ + 8
14   CoreFoundation  __CFRunLoopRun + 1300
15   CoreFoundation  CFRunLoopRunSpecific + 522
16   CoreFoundation  CFRunLoopRunInMode + 106
17   GraphicsServices    GSEventRunModal + 138
18   UIKit   UIApplicationMain + 1136
19   YouDoodle  
AppDelegate.m line 129
main

http://crashes.to/s/c654d14dcfa

iAd 的委托回调：

- (void) bannerView:(ADBannerView *)banner didFailToReceiveAdWithError:(NSError *)error
{
    DLog(@"IAD Failed to load with error %@", error);
    self.adBannerContainer.hidden = YES;
    if (InternetAvailableWithAlert(NO))
    {
        if (self.gadAvailable)
        {
            self.gadBannerContainer.hidden = NO;
        }
        else
        {
            [self requestGAD];
        }
    }
}
- (void) requestGAD
{
    GADRequest* request = [[GADRequest alloc] init];
#if TARGET_IPHONE_SIMULATOR
    request.testDevices = @[GAD_SIMULATOR_ID];
#endif
    self.gadBanner.rootViewController = (self.gadBanner.rootViewController ?: self.viewController);
    [self.gadBanner loadRequest:request];
}

iAd 视图委托是一个永远不会发布的单一实例。即使它已释放，iAd 类委托属性也是一个弱属性，因此它应该自动 nil。

@property (nonatomic, weak) id<ADBannerViewDelegate> delegate;

想法？

Answer 1

这是因为将

Admob SDK 根视图控制器设置回自身，当视图控制器解除分配后，此操作会崩溃。Admob SDK 使用分配引用而不是弱引用，这就是它崩溃的原因。