我在github例子中找到了解决方案，即:

I found solution in the github example, that is:

而不是

xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"

删除 xmlns:ads*** 标签并添加

delete the xmlns:ads*** tag and add

xmlns:ads="http://schemas.android.com/apk/res-auto"

标记到您的 LinearLayout 标记如下:

tag to your LinearLayout tag as follow:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
          xmlns:ads="http://schemas.android.com/apk/res-auto"
          android:orientation="vertical"
          android:layout_width="match_parent"
          android:layout_height="match_parent">
<TextView android:layout_width="match_parent"
          android:layout_height="wrap_content"
          android:text="@string/hello"/>
<com.google.android.gms.ads.AdView android:id="@+id/adView"
                       android:layout_width="match_parent"
                       android:layout_height="wrap_content"
                       ads:adSize="BANNER"
                       ads:adUnitId="INSERT_YOUR_AD_UNIT_ID_HERE"/>
</LinearLayout>

就是这样:)

此xml的github链接