title: Upgrading a Handler with Runnable to lambda expression
body: <p>I want to upgrade this code to use a lambda expression:</p>
  
  <pre><code>Handler handler = new Handler(Looper.getMainLooper());
  handler.postDelayed(new Runnable() {
      @Override
      public void run() {
          missileX = ufoX;
          resetRecent();
          waitForUfoTimer = false;
      }
  }, randomize(20000, 18000));
  </code></pre>
  
  <p>I try it this way but it doesn't compile:</p>
  
  <pre><code>Handler handler2 = new Handler(Looper.getMainLooper());
  handler2.postDelayed(Runnable task = () -&gt; {  
      missileX = ufoX;
      resetRecent();
      waitForUfoTimer = false; 
    }
  }, randomize(20000, 18000));
  </code></pre>
  
  <p>Where are some instructions so that I can learn how to do it? It is preposterous that I must guess the syntax. </p>