Question

它与非页内广告有关，我在Adview中遇到了同样的问题但是通过将Adview添加到xml并在java中引用来解决它但是你不能用插页式广告

public class MainActivity extends Activity {
    AdView adView;
    InterstitialAd interstitial;

    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.test);
        LinearLayout layout = (LinearLayout) findViewById(R.id.test);
        AdView adView = (AdView) this.findViewById(R.id.adView);

        AdRequest adRequest = new AdRequest.Builder()
                .addTestDevice(AdRequest.DEVICE_ID_EMULATOR)
                .addTestDevice("TEST_DEVICE_ID").build();
        adView.loadAd(adRequest);

        InterstitialAd interstitial = new InterstitialAd(this);
        interstitial.setAdUnitId("banner");
        AdRequest adRequest2 = new AdRequest.Builder()
                .addTestDevice(AdRequest.DEVICE_ID_EMULATOR)
                .addTestDevice("TEST_DEVICE_ID").build();
        interstitial.loadAd(adRequest2);
        displayInterstitial();

    }

    public void displayInterstitial() {
        if (interstitial.isLoaded()) {
            interstitial.show();
        }
    }
}

logcat的：

02-21 19:48:29.390: E/AndroidRuntime(1929): FATAL EXCEPTION: main
02-21 19:48:29.390: E/AndroidRuntime(1929): Process: com.adtest, PID: 1929
02-21 19:48:29.390: E/AndroidRuntime(1929): java.lang.RuntimeException: Unable to start activity ComponentInfo{com.adtest/com.adtest.MainActivity}: java.lang.NullPointerException
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2195)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.ActivityThread.handleLaunchActivity(ActivityThread.java:2245)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.ActivityThread.access$800(ActivityThread.java:135)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.ActivityThread$H.handleMessage(ActivityThread.java:1196)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.os.Handler.dispatchMessage(Handler.java:102)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.os.Looper.loop(Looper.java:136)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.ActivityThread.main(ActivityThread.java:5017)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at java.lang.reflect.Method.invokeNative(Native Method)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at java.lang.reflect.Method.invoke(Method.java:515)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at com.android.internal.os.ZygoteInit$MethodAndArgsCaller.run(ZygoteInit.java:779)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at com.android.internal.os.ZygoteInit.main(ZygoteInit.java:595)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at dalvik.system.NativeStart.main(Native Method)
02-21 19:48:29.390: E/AndroidRuntime(1929): Caused by: java.lang.NullPointerException
02-21 19:48:29.390: E/AndroidRuntime(1929):     at com.adtest.MainActivity.displayInterstitial(MainActivity.java:40)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at com.adtest.MainActivity.onCreate(MainActivity.java:35)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.Activity.performCreate(Activity.java:5231)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.Instrumentation.callActivityOnCreate(Instrumentation.java:1087)
02-21 19:48:29.390: E/AndroidRuntime(1929):     at android.app.ActivityThread.performLaunchActivity(ActivityThread.java:2159)
02-21 19:48:29.390: E/AndroidRuntime(1929):     ... 11 more
02-21 19:49:29.530: W/Ads(1929): Timed out waiting for ad response.
02-21 19:49:29.530: W/Ads(1929): Timed out waiting for ad response.
02-21 19:53:29.880: I/Process(1929): Sending signal. PID: 1929 SIG: 9

Answer 1

您已在onCreate()中创建了本地变量，并为其分配了InterstitialAd个实例：

InterstitialAd interstitial = new InterstitialAd(this);

这与您班级中的字段无关，因此当您致电displayInterstitial()并引用班级中的字段时...... null

另外值得注意的是，您使用AdView做同样的事情。

Answer 2

InterstitialAd interstitial = new InterstitialAd(this);

您没有将新实例写入类成员，而是创建局部变量。在开头删除InterstitialAd，你应该没事。

获得NullPointerException但无法看到一个，任何人都可以指出它

2 个答案: