title: user can not change checkbox in radgrid
body: <p>I use this code to add a checkbox column to radgrid.In my program,i want to add row dynamically.but when i use my code and run program,checkbox is disabled for user and he/she can not changed it.what should i do to allow user that cand change checkbox?</p>
  
  <p>my code:</p>
  
  <pre><code>&lt;telerik:GridCheckBoxColumn DataField="Discontinued" HeaderText="Discontinued"
                                        DataType="System.Boolean" ShowFilterIcon="False"&gt;
                                  &lt;/telerik:GridCheckBoxColumn&gt;
  </code></pre>
  
  <p>and dynamically add rows:</p>
  
  <pre><code> DataTable table = new DataTable();
              table.Columns.Add("DeliveryID");
              table.Columns.Add("DeliveryName");
  
              DataRow dr = table.NewRow();
  
              dr["DeliveryName"] = "uk";
  
              table.Rows.Add(dr);
  
              DataRow dr2 = table.NewRow();
  
              dr2["DeliveryName"] = "US";
  
              table.Rows.Add(dr2);
  
  
  
              RadGrid1.DataSource = table;
  
              RadGrid1.Rebind();
  </code></pre>