title: Checkbox input undefined when unchecked - AngularJS
body: <p>I have an issue with my <code>AngularJS</code> checkbox where they become <code>undefined</code> when they are unchecked. Can't figure out why this is happening.</p>
  
  <pre><code>&lt;input type="checkbox" name="available" ng-model="formData.available" ng-true-value="1" ng-false-value="0" required&gt;
  </code></pre>
  
  <p>With the above code; default on page load is <code>0</code>. when Its checked it becomes <code>1</code>. When I uncheck it it becomes <code>undefined</code></p>
  
  <p>Any help appreciated.</p>