title: Handler() delay not working on my custom writing text animation
body: <p>I'm trying to append "..." to my <code>TextView</code> in the form of:</p>
  
  <ol>
  <li>append "."</li>
  <li>2000ms delay</li>
  <li>append "."</li>
  <li>2000ms delay</li>
  <li>append "..."</li>
  </ol>
  
  <p>However when I run my app, it appends all 3 "..." at the same time.</p>
  
  <p><strong>GlobalFunctions.kt</strong></p>
  
  <pre><code>fun writeText(tv: TextView, s: String){
      fun write(letter: Char){
          Handler().postDelayed({tv.append(letter.toString())}, 2000)
      }
      for (letter in s){
          write(letter)
      }
  }
  </code></pre>
  
  <p><strong>Activity.kt</strong></p>
  
  <pre><code>override fun onCreate(savedInstanceState: Bundle?) {
      writeText(chosenPlayer, "...")
  }
  </code></pre>
  
  <p><strong>xml</strong></p>
  
  <pre><code>&lt;TextView
      android:id="@+id/chosenPlayer"
      android:visibility="invisible"
      android:text=""
      android:textStyle="bold"
      android:textColor="@color/colorGreen"
      android:textSize="30dp"/&gt;
  </code></pre>
  
  <p>Any idea what the problem is?</p>