无法加载实时 Admob 广告

Live Admob ads will not load

我在尝试显示来自 Admob 的实时广告时遇到问题。测试广告运行良好,但当我切换到实时广告时,我不断收到此错误

 Unable to get provider com.google.android.gms.ads.MobileAdsInitProvider: 
 java.lang.IllegalStateException: 
 The Google Mobile Ads SDK was initialized incorrectly                                   

我已按照 Admob 提供的文档进行操作并检查了 APP_ID,但仍然不断收到此错误。我似乎无法弄清楚问题是什么。我已经在下面发布了我的代码,有什么建议吗?

AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
package="com.example.whatsfor">

<uses-permission android:name="android.permission.INTERNET"></uses-permission>

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">
    <activity
        android:name=".MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
        <meta-data
            android:name="com.google.android.gms.ads.APPLICATION_ID"
            android:value="ca-app-pub-123123123123-43434323"/>
    </activity>
</application>
</manifest> 

Main.java

public class MainActivity extends AppCompatActivity {
AdView bannerAdView;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main);

    MobileAds.initialize(this, new OnInitializationCompleteListener() {
        @Override
        public void onInitializationComplete(InitializationStatus initializationStatus) {
        }
    });
    bannerAdView = findViewById(R.id.adView);
    AdRequest adRequest = new AdRequest.Builder().build();
    bannerAdView.loadAd(adRequest);
    }}

activity.xml

<com.google.android.gms.ads.AdView
    android:id="@+id/adView"
    app:adSize="BANNER"
    app:adUnitId="ca-app-pub-6969696969/123123123"
    android:layout_width="320dp"
    android:layout_height="53dp"
    android:layout_alignParentBottom="true"
    android:layout_centerHorizontal="true"
    android:layout_marginStart="47dp"
    android:layout_marginLeft="47dp"
    android:layout_marginTop="69dp"
    android:layout_marginEnd="37dp"
    android:layout_marginRight="37dp"
    android:layout_marginBottom="68dp" />

您必须将 App ID <meta-data> 放在 <application> 下,而不是 <activity>.

<application
    android:allowBackup="true"
    android:icon="@mipmap/ic_launcher"
    android:label="@string/app_name"
    android:roundIcon="@mipmap/ic_launcher_round"
    android:supportsRtl="true"
    android:theme="@style/AppTheme">

    <meta-data
        android:name="com.google.android.gms.ads.APPLICATION_ID"
        android:value="ca-app-pub-123123123123-43434323"/>

    <activity
        android:name=".MainActivity"
        android:label="@string/app_name" >
        <intent-filter>
            <action android:name="android.intent.action.MAIN" />
            <category android:name="android.intent.category.LAUNCHER" />
        </intent-filter>
    </activity>
</application>

或者,the Official document提到:

Important: This step is required as of Google Mobile Ads SDK version 17.0.0. Failure to add this tag results in a crash with the message: The Google Mobile Ads SDK was initialized incorrectly.