The ad size and ad unit ID must be set before loadAd when set programmatically

Question

I have no idea what is going on here but I am trying to set my ad unit ID dynamically through code like below and removing it from the XML but still get the error:

Answer 1

I have made it like this

in code

@Override
protected void onCreate(Bundle savedInstanceState)
{
    super.onCreate(savedInstanceState);
    setContentView(R.layout.newone);
    initAdsAccount();
    initAds();
}

private void initAdsAccount()
{
    String accountId = AdsConstants.my_fake_ads_account_id;

    if (AdsConstants.isAdsMode)
    {
        accountId = AdsConstants.my_ads_account_id;
    }

    MobileAds.initialize(this, accountId);
}

private void initAds()
{
    findViewById(R.id.ll_main_screen_container).post(//
            new Runnable()
            {
                @Override
                public void run()
                {
                    LinearLayout adContainer = findViewById(R.id.ll_main_screen_container);
                    AdView mAdView = new AdView(MainActivity.this);
                    mAdView.setAdSize(AdSize.BANNER);

                    if (AdsConstants.isAdsMode)
                    {
                        mAdView.setAdUnitId(AdsConstants.main_screen_bottom_banner_id);
                    }
                    else
                    {
                        mAdView.setAdUnitId(AdsConstants.fake_banner_id);
                    }

                    adContainer.addView(mAdView);
                    AdRequest adRequest = new AdRequest.Builder().build();
                    mAdView.loadAd(adRequest);
                }
            }//
    );
}