所谓激励广告,指的是用户可以选择与之互动来换取应用内奖励的一种广告。本指南介绍了如何将 AdMob 激励广告植入到 Flutter 应用中。
务必用测试广告进行测试
在构建和测试应用时,请确保使用的是测试广告,而不是实际投放的广告。否则,可能会导致您的账号被中止。
对于激励广告,加载测试广告最简便的方法就是使用下面的测试专用广告单元 ID:
Android
ca-app-pub-3940256099942544/5224354917
iOS
ca-app-pub-3940256099942544/1712485313
这些测试广告单元 ID 已经过专门配置,可确保每个请求返回的都是测试广告。您可以在自己应用的编码、测试和调试过程中随意使用这些测试广告单元 ID。只需确保在发布应用前用您自己的广告单元 ID 替换这些测试广告单元 ID 即可。
加载广告
以下示例加载了一个激励广告:
class RewardedExampleState extends State<RewardedExample> { RewardedAd? _rewardedAd; // TODO: replace this test ad unit with your own ad unit. final adUnitId = Platform.isAndroid ? 'ca-app-pub-3940256099942544/5224354917' : 'ca-app-pub-3940256099942544/1712485313'; /// Loads a rewarded ad. void loadAd() { RewardedAd.load( adUnitId: adUnitId, request: const AdRequest(), adLoadCallback: RewardedAdLoadCallback( // Called when an ad is successfully received. onAdLoaded: (ad) { debugPrint('$ad loaded.'); // Keep a reference to the ad so you can show it later. _rewardedAd = ad; }, // Called when an ad request failed. onAdFailedToLoad: (LoadAdError error) { debugPrint('RewardedAd failed to load: $error'); }, )); } }
激励广告事件
通过使用 FullScreenContentCallback
,您可以监听各种广告生命周期事件,例如广告何时展示或何时关闭。在展示广告之前设置 RewardedAd.fullScreenContentCallback
,以接收这些事件的通知。以下示例实现了每个方法,并将消息记录到控制台:
class RewardedExampleState extends State<RewardedExample> { RewardedAd? _rewardedAd; // TODO: replace this test ad unit with your own ad unit. final adUnitId = Platform.isAndroid ? 'ca-app-pub-3940256099942544/5224354917' : 'ca-app-pub-3940256099942544/1712485313'; /// Loads a rewarded ad. void loadAd() { RewardedAd.load( adUnitId: adUnitId, request: const AdRequest(), adLoadCallback: RewardedAdLoadCallback( // Called when an ad is successfully received. onAdLoaded: (ad) { ad.fullScreenContentCallback = FullScreenContentCallback( // Called when the ad showed the full screen content. onAdShowedFullScreenContent: (ad) {}, // Called when an impression occurs on the ad. onAdImpression: (ad) {}, // Called when the ad failed to show full screen content. onAdFailedToShowFullScreenContent: (ad, err) { // Dispose the ad here to free resources. ad.dispose(); }, // Called when the ad dismissed full screen content. onAdDismissedFullScreenContent: (ad) { // Dispose the ad here to free resources. ad.dispose(); }, // Called when a click is recorded for an ad. onAdClicked: (ad) {}); debugPrint('$ad loaded.'); // Keep a reference to the ad so you can show it later. _rewardedAd = ad; }, // Called when an ad request failed. onAdFailedToLoad: (LoadAdError error) { debugPrint('RewardedAd failed to load: $error'); }, )); } }
展示广告
RewardedAd
作为叠加层显示在所有应用内容之上,并以静态方式放置;因此,它无法添加到 Flutter widget 树。您可以通过调用 show()
来选择展示广告的时间。RewardedAd.show()
接受 OnUserEarnedRewardCallback
,系统会在用户获得奖励时调用该事件。请务必实现此事件,在用户观看广告后给予奖励。
_rewardedAd.show(onUserEarnedReward: (AdWithoutView ad, RewardItem rewardItem) { // Reward the user for watching an ad. });
调用 show()
后,以这种方式展示的 Ad
无法以编程方式移除,并且需要用户输入内容。一个 RewardedAd
只能显示一次。后续显示的调用将触发 onAdFailedToShowFullScreenContent
。
当不再需要访问广告时,必须对其进行处置。调用 dispose()
的最佳实践是,在 FullScreenContentCallback.onAdDismissedFullScreenContent
和 FullScreenContentCallback.onAdFailedToShowFullScreenContent
回调中调用。
大功告成!您的应用现在就可以展示激励广告了。