title: Lazy AdMob ads loading
body: <p>I'm loading a simple banner ad in my main activity. The problem is whenever I start application it stucks about 2 sec on white screen and then loads UI. 
  The problem isn't about the app code, because before I added ads app used to launch instantly. This is the code I load ads:<br>
  in <code>onCreate</code>:  </p>
  
  <pre><code>MobileAds.initialize(this, "ca-app-pub-#######")
          val mAdView: AdView = findViewById(R.id.adView)
          mAdView.visibility = View.GONE
          val adRequest = AdRequest.Builder().build()
          val adView = AdView(this)
          adView.adSize = AdSize.BANNER
          adView.adUnitId = "ca-app-pub-3940256099942544/6300978111"  &lt;- test id
          initializeAds(mAdView, adRequest)
  </code></pre>
  
  <p><code>initializeAds()</code>:</p>
  
  <pre><code> fun initializeAds(adView: AdView, adRequest: AdRequest){
          adView.loadAd(adRequest)
          adView.adListener = object : AdListener(){
              override fun onAdLoaded() {
                  super.onAdLoaded()
                  if (adView.visibility == View.GONE) {
                      adView.visibility = View.VISIBLE
                  }
              }
  
              override fun onAdFailedToLoad(p0: Int) {
                  super.onAdFailedToLoad(p0)
                  adView.visibility = View.GONE
              }
          }
      }
  </code></pre>
  
  <p>Is there any way to load ad without UI lag?  </p>