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激励广告自定义事件

前提条件

请求激励广告

在达到广告瀑布流中介链内的自定义事件订单项时，系统会对您在创建自定义事件时提供的类名称调用 loadRewarded:adConfiguration:completionHandler: 方法。在这种情况下，该方法位于 SampleCustomEvent 中，后者随后会调用 SampleCustomEventRewarded 中的 loadRewarded:adConfiguration:completionHandler: 方法。

若要请求激励广告，请创建或修改实现 GADMediationAdapter 和 loadRewarded:adConfiguration:completionHandler: 的类。如果扩展 GADMediationAdapter 的类已存在，请在该类中实现 loadRewarded:adConfiguration:completionHandler:。此外，请创建一个新类来实现 GADMediationRewardedAd。

在我们的自定义事件示例中，SampleCustomEvent 会实现 GADMediationAdapter 接口，然后委托给 SampleCustomEventRewarded。

Swift

import GoogleMobileAds

class SampleCustomEvent: NSObject, GADMediationAdapter {

  fileprivate var rewardedAd: SampleCustomEventRewarded?
  ...

  func loadRewarded(
    for adConfiguration: GADMediationRewardedAdConfiguration,
    completionHandler: @escaping GADMediationRewardedLoadCompletionHandler
  ) {
    self.rewardedAd = SampleCustomEventRewarded()
    self.rewardedAd?.loadRewarded(
      for: adConfiguration, completionHandler: completionHandler)
  }
}

Objective-C

#import "SampleCustomEvent.h"

@implementation SampleCustomEvent
...

SampleCustomEventRewarded *sampleRewarded;

- (void)loadRewardedForAdConfiguration:
            (GADMediationRewardedAdConfiguration *)adConfiguration
                     completionHandler:
                         (GADMediationRewardedLoadCompletionHandler)
                             completionHandler {
  sampleRewarded = [[SampleCustomEventRewarded alloc] init];
  [sampleRewarded loadRewardedForAdConfiguration:adConfiguration
                               completionHandler:completionHandler];
}

SampleCustomEventRewarded 负责执行以下任务：

加载激励广告。
实现 GADMediationRewardedAd 协议。
接收广告事件回调并将其报告给 Google 移动广告 SDK。

AdMob 界面中定义的可选参数包含在广告配置中。此参数可通过 adConfiguration.credentials.settings[@"parameter"] 进行访问。通常，此参数是实例化广告对象时广告联盟 SDK 所需的广告单元标识符。

Swift

class SampleCustomEventRewarded: NSObject, GADMediationRewardedAd {
  /// The Sample Ad Network rewarded ad.
  var nativeAd: SampleRewarded?

  /// The ad event delegate to forward ad rendering events to the Google Mobile Ads SDK.
  var delegate: GADMediationRewardedAdEventDelegate?

  /// Completion handler called after ad load.
  var completionHandler: GADMediationRewardedLoadCompletionHandler?

  func loadRewarded(
    for adConfiguration: GADMediationRewardedAdConfiguration,
    completionHandler: @escaping GADMediationRewardedLoadCompletionHandler
  ) {
    rewarded = SampleRewarded.init(
      adUnitID: adConfiguration.credentials.settings["parameter"] as? String)
    rewarded?.delegate = self
    let adRequest = SampleAdRequest()
    adRequest.testMode = adConfiguration.isTestRequest
    self.completionHandler = completionHandler
    rewarded?.fetchAd(adRequest)
  }
}

Objective-C

#import "SampleCustomEventRewarded.h"

@interface SampleCustomEventRewarded () <SampleRewardedAdDelegate,
                                         GADMediationRewardedAd> {
  /// The sample rewarded ad.
  SampleRewarded *_rewardedAd;

  /// The completion handler to call when the ad loading succeeds or fails.
  GADMediationRewardedLoadCompletionHandler _loadCompletionHandler;

  /// The ad event delegate to forward ad rendering events to the Google Mobile Ads SDK.
  id <GADMediationRewardedAdEventDelegate> _adEventDelegate;
}
@end

- (void)loadRewardedAdForAdConfiguration:(GADMediationRewardedAdConfiguration *)adConfiguration
                       completionHandler:
                           (GADMediationRewardedLoadCompletionHandler)completionHandler {
  __block atomic_flag completionHandlerCalled = ATOMIC_FLAG_INIT;
  __block GADMediationRewardedLoadCompletionHandler originalCompletionHandler =
      [completionHandler copy];

  _loadCompletionHandler = ^id<GADMediationRewardedAdEventDelegate>(
      _Nullable id<GADMediationRewardedAd> ad, NSError *_Nullable error) {
    // Only allow completion handler to be called once.
    if (atomic_flag_test_and_set(&completionHandlerCalled)) {
      return nil;
    }

    id<GADMediationRewardedAdEventDelegate> delegate = nil;
    if (originalCompletionHandler) {
      // Call original handler and hold on to its return value.
      delegate = originalCompletionHandler(ad, error);
    }

    // Release reference to handler. Objects retained by the handler will also be released.
    originalCompletionHandler = nil;

    return delegate;
  };

  NSString *adUnit = adConfiguration.credentials.settings[@"parameter"];
  _rewardedAd = [[SampleRewardedAd alloc] initWithAdUnitID:adUnit];
  _rewardedAd.delegate = self;
  SampleAdRequest *adRequest = [[SampleAdRequest alloc] init];
  adRequest.testMode = adConfiguration.isTestRequest;
  [_rewardedAd fetchAd:adRequest];
}

无论广告是已成功提取还是遇到错误，您都需要调用 GADMediationRewardedLoadCompletionHandler。如果成功，请传递实现 GADMediationRewardedAd 的类，其中错误参数的值为 nil；如果失败，请传递您遇到的错误。

通常，这些方法是在您的适配器所实现的第三方 SDK 的回调中实现的。在此示例中，示例 SDK 具有一个 SampleRewardedAdDelegate 及相关回调：

Swift

func rewardedDidLoad(_ interstitial: SampleRewarded) {
  if let handler = completionHandler {
    delegate = handler(self, nil)
  }
}

func rewarded(
  rewarded: SampleRewarded, didFailToLoadAdWith errorCode: SampleErrorCode
) {
  let error =
    SampleCustomEventUtils.SampleCustomEventErrorWithCodeAndDescription(
      code: SampleCustomEventErrorCode
        .SampleCustomEventErrorAdLoadFailureCallback,
      description:
        "Sample SDK returned an ad load failure callback with error code: \(errorCode)"
    )
  if let handler = completionHandler {
    delegate = handler(nil, error)
  }
}

Objective-C

- (void)rewardedDidLoad:(SampleRewarded *)rewarded {
  _adEventDelegate = _loadCompletionHandler(self, nil);
}

- (void)rewarded:(SampleInterstitial *)rewarded
    didFailToLoadAdWithErrorCode:(SampleErrorCode)errorCode {
  NSError *error = SampleCustomEventErrorWithCodeAndDescription(
      SampleCustomEventErrorAdLoadFailureCallback,
      [NSString stringWithFormat:@"Sample SDK returned an ad load failure "
                                 @"callback with error code: %@",
                                 errorCode]);
  _adEventDelegate = _loadCompletionHandler(nil, error);
}

GADMediationrewardedAd 需要实现 present(viewController:) 方法才能展示广告：

Swift

func present(from viewController: UIViewController) {
  if let rewarded = rewarded, rewarded.isRewardedLoaded {
    rewarded.show()
  }
}

Objective-C

- (void)presentFromViewController:(UIViewController *)viewController {
  if ([_rewardedAd isRewardedLoaded]) {
    [_rewardedAd show];
  } else {
    NSError *error = SampleCustomEventErrorWithCodeAndDescription(
        SampleCustomEventErrorAdNotLoaded,
        [NSString stringWithFormat:
                      @"The rewarded ad failed to present because the ad was not loaded."]);
    [_adEventDelegate didFailToPresentWithError:error]
  }
}

将中介事件转发至 Google 移动广告 SDK

在您调用 GADMediationRewardedLoadCompletionHandler 并返回已加载的广告后，适配器便可以使用返回的 GADMediationRewardedAdEventDelegate 委托对象，将展示事件从第三方 SDK 转发至 Google 移动广告 SDK。SampleCustomEventRewarded 类实现了 SampleRewardedAdDelegate 协议，用于将回调从示例广告联盟转发到 Google 移动广告 SDK。

您的自定义事件必须尽可能多地转发这些回调，以便您的应用从 Google 移动广告 SDK 接收这些等效事件。以下示例展示了如何使用回调：

Swift

func rewardedAdDidPresent(_ rewarded: SampleRewardedAd) {
  delegate?.willPresentFullScreenVideo()
  delegate?.didStartVideo()
}

func rewardedAdUserDidEarnReward(_ rewarded: SampleRewardedAd) {
  GADAdReward aReward = GADAdReward("", rewarded)
  delegate.didRewardUser()
}

Objective-C

- (void)rewardedAdDidPresent:(SampleRewardedAd *)rewardedAd {
  [_adEventDelegate willPresentFullScreenView];
  [_adEventDelegate didStartVideo];
}

- (void)rewardedAd:(nonnull SampleRewardedAd *)rewardedAd
    userDidEarnReward:(NSUInteger)reward {
  GADAdReward *aReward = [[GADAdReward alloc]
      initWithRewardType:@""
            rewardAmount:[NSDecimalNumber numberWithUnsignedInt:reward]];
  [_adEventDelegate didRewardUserWithReward];
}

到这里，我们已经实现针对激励广告的自定义事件。GitHub 上提供了完整的示例。您可在已获支持的广告联盟上直接使用这些示例代码，也可在修改后用于展示自定义事件激励广告。