title: Flutter TextButton splashColor property
body: <p>I was using <code>FlatButton</code> and passed the properties</p>
  <pre><code>FlatButton(
        splashColor: Colors.transparent,
        highlightColor: Colors.transparent,
        child: ..., 
  )
  </code></pre>
  <p>The <a href="https://api.flutter.dev/flutter/material/FlatButton-class.html" rel="noreferrer">documentation says that FlatButton will become obsolete</a>, and to use <code>TextButton</code> instead, but it does not take <code>splashColor</code> or <code>highlightColor</code> properties</p>
  <pre><code>TextButton(                  
      splashColor: Colors.transparent,
      highlightColor: Colors.transparent,
      child: ...,       
  )
  </code></pre>
  <p>does not work. it is not allowed</p>
  <p>I also tried like this</p>
  <pre><code>TextButton(            
    style: ButtonStyle(
      splashColor: Colors.transparent,
      highlightColor: Colors.transparent,
    ),
    child: ..., 
  )
  </code></pre>
  <p>How can I do this? Thank you</p>