When I add the code
<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:tools="http://schemas.android.com/tools"
xmlns:android="http://schemas.android.com/apk/res/android"
android:id="@+id/LinearLayout1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:background="#F0F8FF"
android:orientation="vertical" >
<ListView
android:id="@+id/lvHienThi"
android:layout_width="match_parent"
android:layout_height="wrap_content" >
</ListView>
<com.google.android.gms.ads.AdView
xmlns:ads="http://schemas.android.com/apk/res-auto"
android:id="@+id/adview"
android:layout_width="match_parent"
android:layout_height="wrap_content"
android:layout_gravity="bottom|center"
ads:adSize="BANNER"
ads:adUnitId="@string/ad_unit_id" />
it show me :"No resource identifier found for attribute 'adSize' in package '....'" How can I fix it ? Please help me. Thank you !