java - Android 谷歌广告错误(空引用？)

Question

我实际上在过去的 24 小时里一直陷入这个错误，仍然找不到解决方案错误描述:

11-06 18:53:37.745: E/AndroidRuntime(1698): Caused by: java.lang.NullPointerException: Attempt to invoke virtual method 'void com.google.android.gms.ads.AdView.loadAd(com.google.android.gms.ads.AdRequest)' on a null object reference

这是一些 xml 布局:

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:ads="http://schemas.android.com/apk/lib/com.google.ads"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:background="@drawable/background_pattern"
    android:orientation="vertical" >
.
.
.
.
.
 <com.google.android.gms.ads.AdView
            android:id="@+id/adView"
            android:layout_width="fill_parent"
            android:layout_height="wrap_content"
            android:layout_alignParentBottom="true"
            android:layout_alignParentLeft="true"
            ads:adSize="SMART_BANNER"
            ads:adUnitId="ca-app-pub-xxxxxxx/xxxxxxxx" />

        <TextView
            android:id="@+id/tv_05"
            android:layout_width="wrap_content"
            android:layout_height="wrap_content"
            android:layout_alignParentTop="true"
            android:layout_centerHorizontal="true"
            android:layout_marginTop="40dp"
            android:textAppearance="?android:attr/textAppearanceMedium" />


</LinearLayout>

mainActivity.java 中的 oncreate 方法:

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

        AdView adview = (AdView) this.findViewById(R.id.adView);

        // Request for Ads
        AdRequest adRequest = new AdRequest.Builder()

                // Add a test device to show Test Ads
                .addTestDevice(AdRequest.DEVICE_ID_EMULATOR).addTestDevice("")
                .build();

        adview.loadAd(adRequest);
        // Prepare the Interstitial Ad
        interstitial = new InterstitialAd(mainActivity.this);
        // Insert the Ad Unit ID
        interstitial.setAdUnitId(AppConstants.Interstitial_Id);

        // Load ads into Interstitial Ads
        interstitial.loadAd(adRequest);
.....

我看不到任何错误我检查了所有导入库一切正常请帮帮我，我快没时间了:/

Answer 1

失败是因为它在您的布局中找不到 ID 为 adView 的元素。

确保上面显示的 XML 文件实际上是 activity_main.xml。

并进行干净的构建。