主要Activity代码:MobileAds.initialize(this,getResources().getString(R.string.app_id));mAdView=findViewById(R.id.adView);mAdView.setVisibility(View.VISIBLE);AdRequestadRequest=newAdRequest.Builder().build();mAdView.loadAd(adRequest);main_activity.xml文件当我添加测试ID广告时:ca-app-pub-3940256099942544/630097811