title: set icon after input onChange
body: <p>I want to add icon after input field it will display on change.
  and another icon if its not on focus.</p>
  <p>Can anyone help me please
  i have tried something like below but i don't know how to toggle icon in this.</p>
  <pre><code>&lt;input matInput type=&quot;text&quot; style=&quot;width: 200px;&quot;&gt;
  &lt;button mat-mini-fab  style=&quot;float: right;&quot; color=&quot;primary&quot; (click)=&quot;element.disabled = !element.disabled&quot;&gt;
    &lt;mat-icon&gt;{{element.disabled ? 'home' : 'edit'}}&lt;/mat-icon&gt;
  &lt;/button&gt;
  
  </code></pre>
  <p>Thank you</p>