title: Assign default values while creating new Item
body: <p>This question about Telerik MVC Grid.</p>
  
  <p>I have two Grids with Master->Details relationship. These to grids are loaded using Ajax Binding. I want to create new Item in Details grid and pass ProductId field value from Master grid.
  I have added property below but do not know how to get ProductId from Master grid. I have tried to pass value using ViewBag on Detail child loading it it seems ViewBag is not assigned then Ajax call is performed. Maybe someone know how to solve this problem?</p>
  
  <pre><code>Editable(editing =&gt; editing.DefaultDataItem(new UserViewModel { ProductId = ?????? })
  </code></pre>