原生廣告自訂事件

必要條件

完成自訂事件設定。

請求原生廣告

當刊登序列中介服務鏈中到達自訂事件委刊項時，系統會使用您在建立自訂事件時提供的類別名稱呼叫the loadNativeAd:adConfiguration:completionHandler: method 。在此情況下，該方法位於 SampleCustomEvent 中，接著在 SampleCustomEventNative中呼叫the loadNativeAd:adConfiguration:completionHandler: method 。

如要請求原生廣告，請建立或修改實作 GADMediationAdapter 和 loadNativeAd:adConfiguration:completionHandler: 的類別。如果擴充 GADMediationAdapter 的類別已存在，請在該類別實作 loadNativeAd:adConfiguration:completionHandler:。此外，您也可以建立新類別來實作 GADMediationNativeAd。

在自訂事件範例中，SampleCustomEvent 會實作the GADMediationAdapter interface ，然後委派給SampleCustomEventNative。

Swift

import GoogleMobileAds

class SampleCustomEvent: NSObject, GADMediationAdapter {

  fileprivate var nativeAd: SampleCustomEventNativeAd?

  func loadNativeAd(
    for adConfiguration: GADMediationNativeAdConfiguration,
    completionHandler: @escaping GADMediationNativeAdLoadCompletionHandler
  ) {
    self.nativeAd = SampleCustomEventNativeAd()
    self.nativeAd?.loadNativeAd(
      for: adConfiguration, completionHandler: completionHandler)
  }
}

Objective-C

#import "SampleCustomEvent.h"

@implementation SampleCustomEvent

SampleCustomEventNativeAd *sampleNativeAd;

- (void)loadNativeAdForAdConfiguration:
            (GADMediationNativeAdConfiguration *)adConfiguration
                     completionHandler:
                         (GADMediationNativeAdLoadCompletionHandler)
                             completionHandler {
  sampleNative = [[SampleCustomEventNativeAd alloc] init];
  [sampleNative loadNativeAdForAdConfiguration:adConfiguration
                             completionHandler:completionHandler];
}

「SampleCustomEventNative 」負責以下工作：

• 載入原生廣告

• 導入 GADMediationNativeAd protocol

• 接收及回報 Google Mobile Ads SDK 的廣告事件回呼

廣告設定包含 AdMob UI 中定義的選用參數。您可以透過 adConfiguration.credentials.settings[@"parameter"] 存取這個參數。這個參數通常是廣告聯播網 SDK 在執行個體化廣告物件時所需的廣告單元 ID。

Swift

class SampleCustomEventNativeAd: NSObject, GADMediationNativeAd {
  /// The Sample Ad Network native ad.
  var nativeAd: SampleNativeAd?

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

  /// Completion handler called after ad load
  var completionHandler: GADMediationNativeLoadCompletionHandler?

  func loadNativeAd(
    for adConfiguration: GADMediationNativeAdConfiguration,
    completionHandler: @escaping GADMediationNativeLoadCompletionHandler
  ) {
    let adLoader = SampleNativeAdLoader()
    let sampleRequest = SampleNativeAdRequest()

    // The Google Mobile Ads SDK requires the image assets to be downloaded
    // automatically unless the publisher specifies otherwise by using the
    // GADNativeAdImageAdLoaderOptions object's disableImageLoading property. If
    // your network doesn't have an option like this and instead only ever
    // returns URLs for images (rather than the images themselves), your adapter
    // should download image assets on behalf of the publisher. This should be
    // done after receiving the native ad object from your network's SDK, and
    // before calling the connector's adapter:didReceiveMediatedNativeAd: method.
    sampleRequest.shouldDownloadImages = true
    sampleRequest.preferredImageOrientation = NativeAdImageOrientation.any
    sampleRequest.shouldRequestMultipleImages = false
    let options = adConfiguration.options
    for loaderOptions: GADAdLoaderOptions in options {
      if let imageOptions = loaderOptions as? GADNativeAdImageAdLoaderOptions {
        sampleRequest.shouldRequestMultipleImages =
          imageOptions.shouldRequestMultipleImages
        // If the GADNativeAdImageAdLoaderOptions' disableImageLoading property is
        // YES, the adapter should send just the URLs for the images.
        sampleRequest.shouldDownloadImages = !imageOptions.disableImageLoading
      } else if let mediaOptions = loaderOptions
        as? GADNativeAdMediaAdLoaderOptions
      {
        switch mediaOptions.mediaAspectRatio {
        case GADMediaAspectRatio.landscape:
          sampleRequest.preferredImageOrientation =
            NativeAdImageOrientation.landscape
        case GADMediaAspectRatio.portrait:
          sampleRequest.preferredImageOrientation =
            NativeAdImageOrientation.portrait
        default:
          sampleRequest.preferredImageOrientation = NativeAdImageOrientation.any
        }
      }
    }
    // This custom event uses the server parameter to carry an ad unit ID, which
    // is the most common use case.
    adLoader.delegate = self
    adLoader.adUnitID =
      adConfiguration.credentials.settings["parameter"] as? String
    self.completionHandler = completionHandler
    adLoader.fetchAd(sampleRequest)
  }
}

Objective-C

#import "SampleCustomEventNativeAd.h"

@interface SampleCustomEventNativeAd () <SampleNativeAdDelegate,
                                         GADMediationNativeAd> {
  /// The sample native ad.
  SampleNativeAd *_nativeAd;

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

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

- (void)loadNativeAdForAdConfiguration:
            (GADMediationNativeAdConfiguration *)adConfiguration
                     completionHandler:(GADMediationNativeLoadCompletionHandler)
                                           completionHandler {
  __block atomic_flag completionHandlerCalled = ATOMIC_FLAG_INIT;
  __block GADMediationNativeLoadCompletionHandler originalCompletionHandler =
      [completionHandler copy];

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

    id<GADMediationNativeAdEventDelegate> 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;
  };

  SampleNativeAdLoader *adLoader = [[SampleNativeAdLoader alloc] init];
  SampleNativeAdRequest *sampleRequest = [[SampleNativeAdRequest alloc] init];

  // The Google Mobile Ads SDK requires the image assets to be downloaded
  // automatically unless the publisher specifies otherwise by using the
  // GADNativeAdImageAdLoaderOptions object's disableImageLoading property. If
  // your network doesn't have an option like this and instead only ever returns
  // URLs for images (rather than the images themselves), your adapter should
  // download image assets on behalf of the publisher. This should be done after
  // receiving the native ad object from your network's SDK, and before calling
  // the connector's adapter:didReceiveMediatedNativeAd: method.
  sampleRequest.shouldDownloadImages = YES;

  sampleRequest.preferredImageOrientation = NativeAdImageOrientationAny;
  sampleRequest.shouldRequestMultipleImages = NO;
  sampleRequest.testMode = adConfiguration.isTestRequest;

  for (GADAdLoaderOptions *loaderOptions in adConfiguration.options) {
    if ([loaderOptions isKindOfClass:[GADNativeAdImageAdLoaderOptions class]]) {
      GADNativeAdImageAdLoaderOptions *imageOptions =
          (GADNativeAdImageAdLoaderOptions *)loaderOptions;
      sampleRequest.shouldRequestMultipleImages =
          imageOptions.shouldRequestMultipleImages;

      // If the GADNativeAdImageAdLoaderOptions' disableImageLoading property is
      // YES, the adapter should send just the URLs for the images.
      sampleRequest.shouldDownloadImages = !imageOptions.disableImageLoading;
    } else if ([loaderOptions
                   isKindOfClass:[GADNativeAdMediaAdLoaderOptions class]]) {
      GADNativeAdMediaAdLoaderOptions *mediaOptions =
          (GADNativeAdMediaAdLoaderOptions *)loaderOptions;
      switch (mediaOptions.mediaAspectRatio) {
        case GADMediaAspectRatioLandscape:
          sampleRequest.preferredImageOrientation =
              NativeAdImageOrientationLandscape;
          break;
        case GADMediaAspectRatioPortrait:
          sampleRequest.preferredImageOrientation =
              NativeAdImageOrientationPortrait;
          break;
        default:
          sampleRequest.preferredImageOrientation = NativeAdImageOrientationAny;
          break;
      }
    } else if ([loaderOptions isKindOfClass:[GADNativeAdViewAdOptions class]]) {
      _nativeAdViewAdOptions = (GADNativeAdViewAdOptions *)loaderOptions;
    }
  }

  // This custom event uses the server parameter to carry an ad unit ID, which
  // is the most common use case.
  NSString *adUnit = adConfiguration.credentials.settings[@"parameter"];
  adLoader.adUnitID = adUnit;
  adLoader.delegate = self;

  [adLoader fetchAd:sampleRequest];
}

無論廣告是否成功擷取還是發生錯誤，您都需要呼叫 GADMediationNativeAdLoadCompletionHandler。如果事件成功，請傳遞用於實作 GADMediationNativeAd 且為錯誤參數使用 nil 值的類別；如果發生失敗，請傳遞您遇到的錯誤。

一般來說，這些方法是在轉接程式實作的第三方 SDK 回呼內實作。在這個範例中，範例 SDK 的 SampleNativeAdDelegate 含有相關回呼：

Swift

func adLoader(
  _ adLoader: SampleNativeAdLoader, didReceive nativeAd: SampleNativeAd
) {
  extraAssets = [
    SampleCustomEventConstantsSwift.awesomenessKey: nativeAd.degreeOfAwesomeness
      ?? ""
  ]

  if let image = nativeAd.image {
    images = [GADNativeAdImage(image: image)]
  } else {
    let imageUrl = URL(fileURLWithPath: nativeAd.imageURL)
    images = [GADNativeAdImage(url: imageUrl, scale: nativeAd.imageScale)]
  }
  if let mappedIcon = nativeAd.icon {
    icon = GADNativeAdImage(image: mappedIcon)
  } else {
    let iconURL = URL(fileURLWithPath: nativeAd.iconURL)
    icon = GADNativeAdImage(url: iconURL, scale: nativeAd.iconScale)
  }

  adChoicesView = SampleAdInfoView()
  self.nativeAd = nativeAd
  if let handler = completionHandler {
    delegate = handler(self, nil)
  }
}

func adLoader(
  _ adLoader: SampleNativeAdLoader,
  didFailToLoadAdWith errorCode: SampleErrorCode
) {
  let error =
    SampleCustomEventUtilsSwift.SampleCustomEventErrorWithCodeAndDescription(
      code: SampleCustomEventErrorCodeSwift
        .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)adLoader:(SampleNativeAdLoader *)adLoader
    didReceiveNativeAd:(SampleNativeAd *)nativeAd {
  if (nativeAd.image) {
    _images = @[ [[GADNativeAdImage alloc] initWithImage:nativeAd.image] ];
  } else {
    NSURL *imageURL = [[NSURL alloc] initFileURLWithPath:nativeAd.imageURL];
    _images = @[ [[GADNativeAdImage alloc] initWithURL:imageURL
                                                 scale:nativeAd.imageScale] ];
  }

  if (nativeAd.icon) {
    _icon = [[GADNativeAdImage alloc] initWithImage:nativeAd.icon];
  } else {
    NSURL *iconURL = [[NSURL alloc] initFileURLWithPath:nativeAd.iconURL];
    _icon = [[GADNativeAdImage alloc] initWithURL:iconURL
                                            scale:nativeAd.iconScale];
  }

  // The sample SDK provides an AdChoices view (SampleAdInfoView). If your SDK
  // provides image and click through URLs for its AdChoices icon instead of an
  // actual UIView, the adapter is responsible for downloading the icon image
  // and creating the AdChoices icon view.
  _adChoicesView = [[SampleAdInfoView alloc] init];
  _nativeAd = nativeAd;

  _adEventDelegate = _loadCompletionHandler(self, nil);
}

- (void)adLoader:(SampleNativeAdLoader *)adLoader
    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);
}

對應原生廣告

不同的 SDK 各有專屬的原生廣告格式。舉例來說，其中一個可能會傳回包含「title」欄位的物件，而另一個可能有「headline」欄位。此外，用於追蹤曝光和處理點擊的方法可能依 SDK 而異。

為解決這些問題，當自訂事件從其中介服務 SDK 收到原生廣告物件時，應使用導入 GADMediationNativeAd (例如 SampleCustomEventNativeAd) 的類別來「對應」中介服務 SDK 的原生廣告物件，讓該物件符合 Google Mobile Ads SDK 預期的介面。

我們現在將進一步說明 SampleCustomEventNativeAd 的實作詳細資料。

儲存對應關係

GADMediationNativeAd 應會實作從其他 SDK 屬性對應的特定屬性：

Swift

var nativeAd: SampleNativeAd?

var headline: String? {
  return nativeAd?.headline
}

var images: [GADNativeAdImage]?

var body: String? {
  return nativeAd?.body
}

var icon: GADNativeAdImage?

var callToAction: String? {
  return nativeAd?.callToAction
}

var starRating: NSDecimalNumber? {
  return nativeAd?.starRating
}

var store: String? {
  return nativeAd?.store
}

var price: String? {
  return nativeAd?.price
}

var advertiser: String? {
  return nativeAd?.advertiser
}

var extraAssets: [String: Any]? {
  return [
    SampleCustomEventConstantsSwift.awesomenessKey:
      nativeAd?.degreeOfAwesomeness
      ?? ""
  ]
}

var adChoicesView: UIView?

var mediaView: UIView? {
  return nativeAd?.mediaView
}

Objective-C

/// Used to store the ad's images. In order to implement the
/// GADMediationNativeAd protocol, we use this class to return the images
/// property.
NSArray<GADNativeAdImage *> *_images;

/// Used to store the ad's icon. In order to implement the GADMediationNativeAd
/// protocol, we use this class to return the icon property.
GADNativeAdImage *_icon;

/// Used to store the ad's ad choices view. In order to implement the
/// GADMediationNativeAd protocol, we use this class to return the adChoicesView
/// property.
UIView *_adChoicesView;

- (nullable NSString *)headline {
  return _nativeAd.headline;
}

- (nullable NSArray<GADNativeAdImage *> *)images {
  return _images;
}

- (nullable NSString *)body {
  return _nativeAd.body;
}

- (nullable GADNativeAdImage *)icon {
  return _icon;
}

- (nullable NSString *)callToAction {
  return _nativeAd.callToAction;
}

- (nullable NSDecimalNumber *)starRating {
  return _nativeAd.starRating;
}

- (nullable NSString *)store {
  return _nativeAd.store;
}

- (nullable NSString *)price {
  return _nativeAd.price;
}

- (nullable NSString *)advertiser {
  return _nativeAd.advertiser;
}

- (nullable NSDictionary<NSString *, id> *)extraAssets {
  return
      @{SampleCustomEventExtraKeyAwesomeness : _nativeAd.degreeOfAwesomeness};
}

- (nullable UIView *)adChoicesView {
  return _adChoicesView;
}

- (nullable UIView *)mediaView {
  return _nativeAd.mediaView;
}

- (BOOL)hasVideoContent {
  return self.mediaView != nil;
}

除了 Google Mobile Ads SDK 所定義的素材資源外，某些中介聯播網還可提供額外的素材資源。GADMediationNativeAd 通訊協定包含名為 extraAssets 的方法，Google Mobile Ads SDK 會使用此方法從對應器中擷取上述任何「額外」素材資源。

對應圖片素材資源

對應圖片素材資源會比對應較簡單的資料類型 (例如 NSString 或 double) 複雜。系統可能會自動下載圖片，或以網址值的形式傳回圖片。他們的像素密度也可能有所差異。

為協助您管理這些詳細資料，Google Mobile Ads SDK 提供 GADNativeAdImage 類別。圖片素材資源資訊 (無論是實際 UIImage 物件或只有 NSURL 值) 應使用此類別傳回 Google Mobile Ads SDK。

以下說明對應工具類別如何建立 GADNativeAdImage 來保存圖示圖片：

Swift

if let image = nativeAd.image {
  images = [GADNativeAdImage(image: image)]
} else {
  let imageUrl = URL(fileURLWithPath: nativeAd.imageURL)
  images = [GADNativeAdImage(url: imageUrl, scale: nativeAd.imageScale)]
}

Objective-C

if (nativeAd.image) {
  _images = @[ [[GADNativeAdImage alloc] initWithImage:nativeAd.image] ];
} else {
  NSURL *imageURL = [[NSURL alloc] initFileURLWithPath:nativeAd.imageURL];
  _images = @[ [[GADNativeAdImage alloc] initWithURL:imageURL
                                               scale:nativeAd.imageScale] ];
}

曝光和點擊事件

Google Mobile Ads SDK 和中介服務 SDK 都必須知道曝光或點擊何時發生，但只需要一個 SDK 就能追蹤這些事件。自訂事件可採用兩種不同方法，具體視中介 SDK 是否支援自行追蹤曝光和點擊的方式而定。

使用 Google Mobile Ads SDK 追蹤點擊和曝光

如果中介服務 SDK 不會自行執行曝光和點擊追蹤，但提供記錄點擊和曝光的方法，Google Mobile Ads SDK 就能追蹤這些事件並通知轉接程式。GADMediationNativeAd protocol 包含兩種方法：didRecordImpression: 以及 didRecordClickOnAssetWithName:view:viewController: 自訂事件可實作，用於在中介原生廣告物件呼叫相應的方法：

Swift

func didRecordImpression() {
  nativeAd?.recordImpression()
}

func didRecordClickOnAsset(
  withName assetName: GADUnifiedNativeAssetIdentifier,
  view: UIView,
  wController: UIViewController
) {
  nativeAd?.handleClick(on: view)
}

Objective-C

- (void)didRecordImpression {
  if (self.nativeAd) {
    [self.nativeAd recordImpression];
  }
}

- (void)didRecordClickOnAssetWithName:(GADUnifiedNativeAssetIdentifier)assetName
                                 view:(UIView *)view
                       viewController:(UIViewController *)viewController {
  if (self.nativeAd) {
    [self.nativeAd handleClickOnView:view];
  }
}

由於導入 GADMediationNativeAd protocol通訊協定的類別會保留對範例 SDK 的原生廣告物件的參照，因此可以針對該物件呼叫適當的方法，藉此回報點擊或曝光。請注意，didRecordClickOnAssetWithName:view:viewController: 方法使用單一參數：與接收點擊的原生廣告素材資源相對應的 View 物件。

使用中介服務 SDK 追蹤點擊和曝光

有些採用中介服務的 SDK 可能會想自行追蹤點擊和曝光次數，在這種情況下，應實作 handlesUserClicks 和 handlesUserImpressions 方法，如以下程式碼片段所示。傳回 YES，即表示您表示自訂事件負責追蹤這些事件，並在這些事件發生時通知 Google Mobile Ads SDK。

如果自訂事件會覆寫點擊和曝光追蹤，可以使用 didRenderInView: 訊息將原生廣告的檢視畫面傳送至中介 SDK 的原生廣告物件，讓中介服務 SDK 進行實際追蹤。自訂事件範例專案中的範例 SDK (這是本指南的程式碼片段的來源) 並未使用這個方法。如果支援，自訂事件程式碼就會呼叫 setNativeAdView:view: 方法，如以下程式碼片段所示：

Swift

func handlesUserClicks() -> Bool {
  return true
}
func handlesUserImpressions() -> Bool {
  return true
}

func didRender(
  in view: UIView, clickableAssetViews: [GADNativeAssetIdentifier: UIView],
  nonclickableAssetViews: [GADNativeAssetIdentifier: UIView],
  viewController: UIViewController
) {
  // This method is called when the native ad view is rendered. Here you would pass the UIView
  // back to the mediated network's SDK.
  self.nativeAd?.setNativeAdView(view)
}

Objective-C

- (BOOL)handlesUserClicks {
  return YES;
}

- (BOOL)handlesUserImpressions {
  return YES;
}

- (void)didRenderInView:(UIView *)view
       clickableAssetViews:(NSDictionary<GADNativeAssetIdentifier, UIView *> *)
                               clickableAssetViews
    nonclickableAssetViews:(NSDictionary<GADNativeAssetIdentifier, UIView *> *)
                               nonclickableAssetViews
            viewController:(UIViewController *)viewController {
  // This method is called when the native ad view is rendered. Here you would
  // pass the UIView back to the mediated network's SDK. Playing video using
  // SampleNativeAd's playVideo method
  [_nativeAd setNativeAdView:view];
}

將中介服務事件轉送至 Google Mobile Ads SDK

使用已載入的廣告呼叫 GADMediationNativeLoadCompletionHandler 後，轉接程式即可使用傳回的 GADMediationNativeAdEventDelegate 委派物件，將顯示事件從第三方 SDK 轉送至 Google Mobile Ads SDK。

您的自訂事件必須盡可能轉送這些回呼，才能讓應用程式從 Google Mobile Ads SDK 接收這些對等事件。以下是回呼的使用範例：

系統隨即會完成原生廣告的自訂事件導入。您可以在 GitHub 取得完整範例。