原生廣告會使用平台原生的 UI 元件向使用者顯示，例如 Android 上的 View 或 iOS 上的 UIView。
本指南將說明如何使用特定平台程式碼載入、顯示及自訂原生廣告。
必要條件
請務必使用測試廣告進行測試
建構及測試應用程式時，請務必使用測試廣告，而非實際的正式版廣告。如要載入測試廣告，最簡單的方法是使用原生廣告專用的測試廣告單元 ID：
/21775744923/example/native
測試廣告單元會在每個請求中傳回測試廣告，因此您可以在編寫程式碼、測試及偵錯時，在自己的應用程式中使用這些廣告單元。不過，請務必在發布應用程式前，將這些廣告單元替換為您自己的廣告單元 ID。
平台專屬設定
如要建立原生廣告，您必須為 iOS 和 Android 編寫平台專屬程式碼，然後修改 Dart 實作，充分發揮原生程式碼變更的優勢。
Android
匯入外掛程式
Google 行動廣告外掛程式的 Android 實作需要實作 NativeAdFactory API 的類別。如要在 Android 專案中參照此 API，請在 settings.gradle 中加入下列行：
def flutterProjectRoot = rootProject.projectDir.parentFile.toPath()
def plugins = new Properties()
def pluginsFile = new File(flutterProjectRoot.toFile(), '.flutter-plugins')
if (pluginsFile.exists()) {
pluginsFile.withInputStream { stream -> plugins.load(stream) }
}
plugins.each { name, path ->
def pluginDirectory = flutterProjectRoot.resolve(path).resolve('android').toFile()
include ":$name"
project(":$name").projectDir = pluginDirectory
}
實作 NativeAdFactory
接下來，請建立導入 NativeAdFactory 並覆寫 createNativeAd() 方法的類別。
package io.flutter.plugins.googlemobileadsexample;
import android.graphics.Color;
import android.view.LayoutInflater;
import android.widget.TextView;
import com.google.android.gms.ads.nativead.NativeAd;
import com.google.android.gms.ads.nativead.NativeAdView;
import io.flutter.plugins.googlemobileads.GoogleMobileAdsPlugin.NativeAdFactory;
import java.util.Map;
/**
* my_native_ad.xml can be found at
* github.com/googleads/googleads-mobile-flutter/blob/main/packages/google_mobile_ads/
* example/android/app/src/main/res/layout/my_native_ad.xml
*/
class NativeAdFactoryExample implements NativeAdFactory {
private final LayoutInflater layoutInflater;
NativeAdFactoryExample(LayoutInflater layoutInflater) {
this.layoutInflater = layoutInflater;
}
@Override
public NativeAdView createNativeAd(
NativeAd nativeAd, Map<String, Object> customOptions) {
final NativeAdView adView =
(NativeAdView) layoutInflater.inflate(R.layout.my_native_ad, null);
// Set the media view.
adView.setMediaView((MediaView) adView.findViewById(R.id.ad_media));
// Set other ad assets.
adView.setHeadlineView(adView.findViewById(R.id.ad_headline));
adView.setBodyView(adView.findViewById(R.id.ad_body));
adView.setCallToActionView(adView.findViewById(R.id.ad_call_to_action));
adView.setIconView(adView.findViewById(R.id.ad_app_icon));
adView.setPriceView(adView.findViewById(R.id.ad_price));
adView.setStarRatingView(adView.findViewById(R.id.ad_stars));
adView.setStoreView(adView.findViewById(R.id.ad_store));
adView.setAdvertiserView(adView.findViewById(R.id.ad_advertiser));
// The headline and mediaContent are guaranteed to be in every NativeAd.
((TextView) adView.getHeadlineView()).setText(nativeAd.getHeadline());
adView.getMediaView().setMediaContent(nativeAd.getMediaContent());
// These assets aren't guaranteed to be in every NativeAd, so it's important to
// check before trying to display them.
if (nativeAd.getBody() == null) {
adView.getBodyView().setVisibility(View.INVISIBLE);
} else {
adView.getBodyView().setVisibility(View.VISIBLE);
((TextView) adView.getBodyView()).setText(nativeAd.getBody());
}
if (nativeAd.getCallToAction() == null) {
adView.getCallToActionView().setVisibility(View.INVISIBLE);
} else {
adView.getCallToActionView().setVisibility(View.VISIBLE);
((Button) adView.getCallToActionView()).setText(nativeAd.getCallToAction());
}
if (nativeAd.getIcon() == null) {
adView.getIconView().setVisibility(View.GONE);
} else {
((ImageView) adView.getIconView()).setImageDrawable(nativeAd.getIcon().getDrawable());
adView.getIconView().setVisibility(View.VISIBLE);
}
if (nativeAd.getPrice() == null) {
adView.getPriceView().setVisibility(View.INVISIBLE);
} else {
adView.getPriceView().setVisibility(View.VISIBLE);
((TextView) adView.getPriceView()).setText(nativeAd.getPrice());
}
if (nativeAd.getStore() == null) {
adView.getStoreView().setVisibility(View.INVISIBLE);
} else {
adView.getStoreView().setVisibility(View.VISIBLE);
((TextView) adView.getStoreView()).setText(nativeAd.getStore());
}
if (nativeAd.getStarRating() == null) {
adView.getStarRatingView().setVisibility(View.INVISIBLE);
} else {
((RatingBar) adView.getStarRatingView()).setRating(nativeAd.getStarRating()
.floatValue());
adView.getStarRatingView().setVisibility(View.VISIBLE);
}
if (nativeAd.getAdvertiser() == null) {
adView.getAdvertiserView().setVisibility(View.INVISIBLE);
} else {
adView.getAdvertiserView().setVisibility(View.VISIBLE);
((TextView) adView.getAdvertiserView()).setText(nativeAd.getAdvertiser());
}
// This method tells the Google Mobile Ads SDK that you have finished populating your
// native ad view with this native ad.
adView.setNativeAd(nativeAd);
return adView;
}
}
如需設定 NativeAdView 版面配置的範例，請參閱 my_native_ad.xml。
註冊 NativeAdFactory
呼叫 MainActivity.configureFlutterEngine(FlutterEngine) 時，每個 NativeAdFactory 實作項目都必須使用 factoryId (專屬的 String ID) 註冊。稍後從 Dart 程式碼例項化原生廣告時，會使用 factoryId。
您可以為應用程式使用的每個獨特原生廣告版面配置實作及註冊 NativeAdFactory，也可以使用單一 NativeAdFactory 處理所有版面配置。
請注意，使用新增至應用程式建構時，NativeAdFactory 也應在 cleanUpFlutterEngine(engine) 中取消註冊。
建立 NativeAdFactoryExample 後，請按照下列方式設定 MainActivity：
package my.app.path;
import io.flutter.embedding.android.FlutterActivity;
import io.flutter.embedding.engine.FlutterEngine;
import io.flutter.plugins.googlemobileads.GoogleMobileAdsPlugin;
public class MainActivity extends FlutterActivity {
@Override
public void configureFlutterEngine(FlutterEngine flutterEngine) {
flutterEngine.getPlugins().add(new GoogleMobileAdsPlugin());
super.configureFlutterEngine(flutterEngine);
GoogleMobileAdsPlugin.registerNativeAdFactory(flutterEngine,
"adFactoryExample", NativeAdFactoryExample());
}
@Override
public void cleanUpFlutterEngine(FlutterEngine flutterEngine) {
GoogleMobileAdsPlugin.unregisterNativeAdFactory(flutterEngine, "adFactoryExample");
}
}
iOS
實作 NativeAdFactory
Google 行動廣告外掛程式的 iOS 實作需要實作 FLTNativeAdFactory API 的類別。建立實作 NativeAdFactory 的類別，並實作 createNativeAd() 方法。
#import "FLTGoogleMobileAdsPlugin.h"
/**
* The example NativeAdView.xib can be found at
* github.com/googleads/googleads-mobile-flutter/blob/main/packages/google_mobile_ads/
* example/ios/Runner/NativeAdView.xib
*/
@interface NativeAdFactoryExample : NSObject <FLTNativeAdFactory>
@end
@implementation NativeAdFactoryExample
- (GADNativeAdView *)createNativeAd:(GADNativeAd *)nativeAd
customOptions:(NSDictionary *)customOptions {
// Create and place the ad in the view hierarchy.
GADNativeAdView *adView =
[[NSBundle mainBundle] loadNibNamed:@"NativeAdView" owner:nil options:nil].firstObject;
// Populate the native ad view with the native ad assets.
// The headline is guaranteed to be present in every native ad.
((UILabel *)adView.headlineView).text = nativeAd.headline;
// These assets are not guaranteed to be present. Check that they are before
// showing or hiding them.
((UILabel *)adView.bodyView).text = nativeAd.body;
adView.bodyView.hidden = nativeAd.body ? NO : YES;
[((UIButton *)adView.callToActionView) setTitle:nativeAd.callToAction
forState:UIControlStateNormal];
adView.callToActionView.hidden = nativeAd.callToAction ? NO : YES;
((UIImageView *)adView.iconView).image = nativeAd.icon.image;
adView.iconView.hidden = nativeAd.icon ? NO : YES;
((UILabel *)adView.storeView).text = nativeAd.store;
adView.storeView.hidden = nativeAd.store ? NO : YES;
((UILabel *)adView.priceView).text = nativeAd.price;
adView.priceView.hidden = nativeAd.price ? NO : YES;
((UILabel *)adView.advertiserView).text = nativeAd.advertiser;
adView.advertiserView.hidden = nativeAd.advertiser ? NO : YES;
// In order for the SDK to process touch events properly, user interaction
// should be disabled.
adView.callToActionView.userInteractionEnabled = NO;
// Associate the native ad view with the native ad object. This is
// required to make the ad clickable.
// Note: this should always be done after populating the ad views.
adView.nativeAd = nativeAd;
return adView;
}
@end
如需設定 GADNativeAdView 版面配置的範例，請參閱 NativeAdView.xib。
註冊 NativeAdFactory
每個 FLTNativeAdFactory 都必須在 registerNativeAdFactory:factoryId:nativeAdFactory: 中註冊 factoryId (專屬的 String 識別碼)。稍後從 Dart 程式碼例項化原生廣告時，會使用 factoryId。
您可以針對應用程式使用的每個獨特原生廣告版面配置實作及註冊 FLTNativeAdFactory，也可以使用單一 FLTNativeAdFactory 處理所有版面配置。
建立 FLTNativeAdFactory 後，請按照下列方式設定 AppDelegate：
#import "FLTGoogleMobileAdsPlugin.h"
#import "NativeAdFactoryExample.h"
@implementation AppDelegate
- (BOOL)application:(UIApplication *)application
didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
[GeneratedPluginRegistrant registerWithRegistry:self];
// Must be added after GeneratedPluginRegistrant registerWithRegistry:self];
// is called.
NativeAdFactoryExample *nativeAdFactory = [[NativeAdFactoryExample alloc] init];
[FLTGoogleMobileAdsPlugin registerNativeAdFactory:self
factoryId:@"adFactoryExample"
nativeAdFactory:nativeAdFactory];
return [super application:application didFinishLaunchingWithOptions:launchOptions];
}
@end
載入廣告
新增平台專屬程式碼後，請改用 Dart 載入廣告。請確認 factoryID 與您先前註冊的 ID 相符。
class NativeExampleState extends State<NativeExample> {
NativeAd? _nativeAd;
bool _nativeAdIsLoaded = false;
// TODO: replace this test ad unit with your own ad unit.
final _adUnitId = '/21775744923/example/native';
/// Loads a native ad.
void loadAd() {
_nativeAd = NativeAd(
adUnitId: _adUnitId,
// Factory ID registered by your native ad factory implementation.
factoryId: 'adFactoryExample',
listener: NativeAdListener(
onAdLoaded: (ad) {
print('$NativeAd loaded.');
setState(() {
_nativeAdIsLoaded = true;
});
},
onAdFailedToLoad: (ad, error) {
// Dispose the ad here to free resources.
print('$NativeAd failedToLoad: $error');
ad.dispose();
},
),
request: const AdManagerAdRequest(),
// Optional: Pass custom options to your native ad factory implementation.
customOptions: {'custom-option-1', 'custom-value-1'}
);
_nativeAd.load();
}
}
原生廣告事件
如要接收與原生廣告互動相關的事件通知，請使用廣告的 listener 屬性。接著，實作 NativeAdListener 以接收廣告事件回呼。
class NativeExampleState extends State<NativeExample> {
NativeAd? _nativeAd;
bool _nativeAdIsLoaded = false;
// TODO: replace this test ad unit with your own ad unit.
final _adUnitId = '/21775744923/example/native';
/// Loads a native ad.
void loadAd() {
_nativeAd = NativeAd(
adUnitId: _adUnitId,
// Factory ID registered by your native ad factory implementation.
factoryId: 'adFactoryExample',
listener: NativeAdListener(
onAdLoaded: (ad) {
print('$NativeAd loaded.');
setState(() {
_nativeAdIsLoaded = true;
});
},
onAdFailedToLoad: (ad, error) {
// Dispose the ad here to free resources.
print('$NativeAd failedToLoad: $error');
ad.dispose();
},
// Called when a click is recorded for a NativeAd.
onAdClicked: (ad) {},
// Called when an impression occurs on the ad.
onAdImpression: (ad) {},
// Called when an ad removes an overlay that covers the screen.
onAdClosed: (ad) {},
// Called when an ad opens an overlay that covers the screen.
onAdOpened: (ad) {},
// For iOS only. Called before dismissing a full screen view
onAdWillDismissScreen: (ad) {},
// Called when an ad receives revenue value.
onPaidEvent: (ad, valueMicros, precision, currencyCode) {},
),
request: const AdManagerAdRequest(),
// Optional: Pass custom options to your native ad factory implementation.
customOptions: {'custom-option-1', 'custom-value-1'}
);
_nativeAd.load();
}
}
多媒體廣告
如要將 NativeAd 顯示為小工具，您必須在呼叫 load() 後，使用支援的廣告將 AdWidget 例項化。您可以在呼叫 load() 之前建立小工具，但必須先呼叫 load()，才能將其新增至小工具樹狀結構。
AdWidget 會繼承 Flutter 的 Widget 類別，並可像其他小工具一樣使用。在 iOS 上，請務必將小工具放入具有指定寬度和高度的容器中。否則廣告可能無法顯示。
final Container adContainer = Container(
alignment: Alignment.center,
child: AdWidget adWidget = AdWidget(ad: _nativeAd!),
width: WIDTH,
height: HEIGHT,
);
Dispose 廣告
當不再需要存取 NativeAd 時，必須將其處置。如要瞭解何時呼叫 dispose() 的最佳做法，請在與原生廣告相關聯的 AdWidget 從小工具樹狀結構中移除後，在 AdListener.onAdFailedToLoad() 回呼中呼叫 dispose()。