title: Choose Data for a row in Vaadin's grid using a combobox
body: <p>I'd like to do the following using vaadin's <strong>grid</strong> (not table ! ). I have a list of java beans and each instance within this list serves as a data source for one row in the grid. 
  The grid should behave in the following way:</p>
  
  <ul>
  <li>Only the 1st column should be editable and the editor here is Combobox. Its list of possible values are all the beans available in the system.</li>
  <li>the values in the other columns are read-only and are in fact values of the other fields of the bean</li>
  <li><em>(This is the crucial part)</em> <strong>The user can edit the row in the following way</strong>: He selects from the combobox (in the 1st column) the bean he wants to be displayed in that particular row and after hitting save in the grid row's editor, this row gets saved to the Underlying Fieldgroup</li>
  </ul>
  
  <p>For the bean let's assume (simplified):</p>
  
  <pre><code>public class OfficeLocationDTO {
  
      private String locationCode;
      private String locationName;
  
      private CountryDTO country;
  
      // getters, seteers, etc. ommitted  
  }
  </code></pre>
  
  <p>For the Data to be filled into the combobox:</p>
  
  <pre><code>List&lt;OfficeLocationDTO&gt; officelocations = ..
  </code></pre>
  
  <p>Could You provide me with hints or links how to solve this task? I have not found yet any similar solution and everything I have tried so far did not work as a whole.
  Thank You in advance !</p>