Google AdMob简单集成，主要代码，包含提前缓存一个广告

1.主要流程不说了，官方很详细（如果要在谷歌市场上架，请一定按照规定集成，否则有下架风险）
主要代码分享一下

private String TAG = "AdmobLog------>";
private RewardedAd rewardedAd;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);
    initialize(this, new OnInitializationCompleteListener() {
        @Override
        public void onInitializationComplete(InitializationStatus initializationStatus) {

        }
    });

    rewardedAd = new RewardedAd(this,
            "ca-app-pub-3940256099942544/5224354917");

    RewardedAdLoadCallback adLoadCallback = new RewardedAdLoadCallback() {
        @Override
        public void onRewardedAdLoaded() {
            // Ad successfully loaded.
            Log.d(TAG,"加载成功");
        }

        @Override
        public void onRewardedAdFailedToLoad(int errorCode) {
            // Ad failed to load.
            Log.d(TAG,"加载失败");
        }
    };
    rewardedAd.loadAd(new AdRequest.Builder().build(), adLoadCallback);
}

public void button(View view) {
    if (rewardedAd.isLoaded()) {
        Activity activityContext = MainActivity.this;
        RewardedAdCallback adCallback = new RewardedAdCallback() {
            @Override
            public void onRewardedAdOpened() {
                // Ad opened.
                Log.d(TAG,"广告打开");
            }

            @Override
            public void onRewardedAdClosed() {
                // Ad closed.
                Log.d(TAG,"广告关闭");
            }

            @Override
            public void onUserEarnedReward(@NonNull RewardItem reward) {
                // User earned reward.
                Log.d(TAG,"获得奖励");
            }

            @Override
            public void onRewardedAdFailedToShow(int errorCode) {
                // Ad failed to display.
                Log.d(TAG,"失败播放");
            }
        };
        rewardedAd.show(activityContext, adCallback);
        onRewardedAdClosed();
    } else {
        Log.d(TAG, "奖励广告尚未加载");
    }
}

public RewardedAd createAndLoadRewardedAd() {
    RewardedAd rewardedAd = new RewardedAd(this,
            "ca-app-pub-3940256099942544/5224354917");
    RewardedAdLoadCallback adLoadCallback = new RewardedAdLoadCallback() {
        @Override
        public void onRewardedAdLoaded() {
            // Ad successfully loaded.
            Log.d(TAG,"预加载成功");
        }

        @Override
        public void onRewardedAdFailedToLoad(int errorCode) {
            // Ad failed to load.
            Log.d(TAG,"预加载失败");
        }
    };
    rewardedAd.loadAd(new AdRequest.Builder().build(), adLoadCallback);
    return rewardedAd;
}

public void onRewardedAdClosed() {
    this.rewardedAd = createAndLoadRewardedAd();
}