title: How to add fxFlex directive conditionally
body: <p>Is it possible to add fxFlex directive from <strong>@angular/flex-layout</strong> depending on some value? </p>
  
  <p>For example, I have a situation like this:</p>
  
  <pre><code>&lt;div [attr.fxFlex]="someCondition"&gt;&lt;/div&gt;
  </code></pre>
  
  <p>This does not work for me but I need fxFlex to be applied only if a condition is true.</p>