title: How to load JSON dynamic tree data in SmartGWT TreeGrid
body: <p>I have a JSON tree structure that is generated dinamically, this means the keys and the structure are unknown and it can change in every request, the only common property in every object are the <em>oldValue</em> and <em>newValue</em> keys...</p>
  
  <p>the JSON looks like this:</p>
  
  <pre><code>{
  "obj1": 
      {"oldValue": "foo", "newValue": "foofoo"},
  "obj2": 
      {"obj2_1": 
          {"oldValue": null, "newValue": "foo"}
      },
      {"obj2_2": 
          {"obj2_2_1": 
              {"oldValue": "foo", "newValue": "foofoo"}           
          },
          {"obj2_2_2": 
              {"oldValue": "foo1", "newValue": null}          
          }
      }
  }
  </code></pre>
  
  <p>How can I load this data in a TreeGrid dinamically? Is it possible to get to the deepest key using XPath?</p>