插页式广告返回空值

Question

我为Android编写了一个名为"Trumple Run"的应用程序。就像名字说的，这是一款Jump & Run游戏，我想尽快发布它。在此之前，我想从 AdMob 实现插页式广告。我遵循了实施广告的官方指南，但是当我尝试显示添加内容时，该应用程序总是崩溃。这是我的MainActivity中的一些代码(信息：我删除了与该问题无关的代码;方法addzeigen()是从另一个类调用的)

public class Main_activity extends Activity {
private InterstitialAd mInterstitial;
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState); 
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN); //Fullscreen
DisplayMetrics metrics = getResources().getDisplayMetrics(); //Display größe herausfinden
V.Bildbreite = metrics.widthPixels;
V.Bildhöhe = metrics.heightPixels;

addladen();

V.v = new View(this);
setContentView(V.v);
}

public void addladen(){
mInterstitial = new InterstitialAd(this);
mInterstitial.setAdUnitId("ca-app-pub-3940256099942544/1033173712");
AdRequest request = new AdRequest.Builder().build();
mInterstitial.loadAd(request);
}

public void addzeigen(){
if(mInterstitial.isLoaded()){
mInterstitial.show();
addladen();
}
}

我查看了 StackTrace 以找到问题的原因，这两行表示插页式广告尚未实例化(返回空值)。

java.lang.NullPointerException: Attempt to invoke virtual method 'boolean com.google.android.gms.ads.InterstitialAd.isLoaded()' on a null object reference

正因为如此，我在 addladen() 方法中添加了一个空检查器以防止崩溃。

public void addzeigen(){
if(mInterstitial != null && mInterstitial.isLoaded()){
mInterstitial.show();
addladen();
}
}

但是为什么我的插页式广告对象为空？我没有在我的addladen()方法中以正确的方式实例化它吗？我已经在互联网上搜索了很长时间，但没有找到解决方案并询问了AdMob支持，但他们说我应该在这里问，因为这是一个实施问题。如何修改代码以确保我的插页式广告不为空？如果你能帮助我，我会很高兴。

Answer 1

创建应用程序以打开应用程序时，添加即时负载

public class MyApplication extends Application {
public InterstitialAd mInterstitialAd;
private AppOpenManager appOpenAdManager;
private Activity currentActivity;
private int check = 0;
public AdLoader adLoader;
@Override
public void onCreate() {
super.onCreate();
MobileAds.initialize(
this,
new OnInitializationCompleteListener() {
@Override
public void onInitializationComplete(
@NonNull InitializationStatus initializationStatus) {
}
});
appOpenAdManager = new AppOpenManager();
loadInterstitial(AD_UNIT_ID_INTERSTITIAL_ADS);
}
public void loadInterstitial(String id) {
AdRequest adRequest = new AdRequest.Builder().build();
InterstitialAd.load(
this,
id,
adRequest,
new InterstitialAdLoadCallback() {
@Override
public void onAdLoaded(@NonNull InterstitialAd interstitialAd) {
mInterstitialAd = interstitialAd;
interstitialAd.setFullScreenContentCallback(
new FullScreenContentCallback() {
@Override
public void onAdDismissedFullScreenContent() {
mInterstitialAd = null;
}
@Override
public void onAdFailedToShowFullScreenContent(AdError adError) {
// Called when fullscreen content failed to show.
// Make sure to set your reference to null so you don't
// show it a second time.
mInterstitialAd = null;
}
@Override
public void onAdShowedFullScreenContent() {
}
});
}
@Override
public void onAdFailedToLoad(@NonNull LoadAdError loadAdError) {
mInterstitialAd = null;
}
});
}

} 然后你创建类检查异常发生加载和打开应用程序

public class LoadInterstitialAds {
private static LoadInterstitialAds instance;
private InterstitialAd mInterstitialAd;
public static LoadInterstitialAds getInstance() {
if (instance == null) {
return new LoadInterstitialAds();
}
return instance;
}
public void openAdsThenOpenActivity(Activity activity, InterstitialAdsListener listener) {
Application application = activity.getApplication();
if (application instanceof MyApplication) {
LoadInterstitialAds.this.mInterstitialAd = ((MyApplication) application).mInterstitialAd;
if (LoadInterstitialAds.this.mInterstitialAd != null) {
LoadInterstitialAds.this.mInterstitialAd.show(activity);
LoadInterstitialAds.this.mInterstitialAd.setFullScreenContentCallback(new FullScreenContentCallback() {
@Override
public void onAdDismissedFullScreenContent() {
listener.onStartActivity();
((MyApplication) application).loadInterstitial(AD_UNIT_ID_INTERSTITIAL_ADS);
}
@Override
public void onAdFailedToShowFullScreenContent(@NonNull AdError adError) {
((MyApplication) application).loadInterstitial(AD_UNIT_ID_INTERSTITIAL_ADS);
listener.onStartActivity();
}
});
} else {
((MyApplication) application).loadInterstitial(AD_UNIT_ID_INTERSTITIAL_ADS);
listener.onStartActivity();
}
}
}

} 创建接口侦听器以方便调用

public interface InterstitialAdsListener {
void onStartActivity();

} 最后，在要显示的任何位置运行此代码

LoadInterstitialAds loadInterstitialAds = LoadInterstitialAds.getInstance();
loadInterstitialAds.openAdsThenOpenActivity(getActivity(), ()->{
// your process
});