title: How to select parent view model in Knockout?
body: <p>I using two view models, <code>mainViewModel</code> and <code>filterViewModel</code> in my page, where <code>filterViewModel</code> is instanced by <code>mainViewModel</code></p>
  
  <pre><code>function mainViewModel() {
      this.data   = ko.observableArray();
      this.filter = new filterViewModel();
  }
  
  function filterViewModel() {
      this.filter = function() {
          // ajax blablabla
      }
  }
  </code></pre>
  
  <p>How to can I access my <code>mainViewModel</code> from <code>filterViewModel</code> for set ajax result, executed by <code>filterViewModel</code>, to <code>data</code> variable in your parent view model?</p>