Angular 2 Radio Button Validation with ngModel
<p><a href="https://angular.io/docs/ts/latest/guide/forms.html" rel="noreferrer">Angular 2's documentation</a> tells about the form validation. But only for input fields type text. My question is for Radio Buttons.</p>

<p>Here is HTML:</p>

<pre><code>&lt;input type="radio" required name='gender' value='Male' [(ngModel)]='gender'&gt;Male
&lt;input type="radio" required name='gender' value='Female' [(ngModel)]='gender'&gt;Female
&lt;button type='button' [disabled]="??"&gt;Next&lt;button&gt;
</code></pre>

<p>How to set disabled property to true if user hasn't selected any value.</p>