MoPubNativeNetworkListener.java

@Override
public void onNativeLoad(final NativeAd nativeAd) {
    nativeAd.setMoPubNativeEventListener(this);
    nativeAd.renderAdView(view);
    nativeAd.prepare(view);
}

@Override
public void onNativeFail(final NativeErrorCode errorCode) {
    Log.w(this.getClass().getSimpleName(), errorCode.toString());
    
    // Handle different kinds of error
    // E.g. hide the empty ad view, or log the error to your server
}