title: GridView Column validation, display error message don't loose focus
body: <p>I need to validate a gridView column such as the sum of all elements in the column are &lt;=100; </p>
  
  <p>If the user enters a value and the sum exceeds the limit i want to display a custom error message.</p>
  
  <p>I've tried using this event on the column's repositoryedit: </p>
  
  <pre><code> void pinEditRepositoryItem_Validating(object sender, System.ComponentModel.CancelEventArgs e)
      {
          e.Cancel = true;
          gridview1.SetColumnError(m_imixGridView.Columns["MyColumn"], "ColumnSum must be &lt;= 100", DevExpress.XtraEditors.DXErrorProvider.ErrorType.Critical);
      }
  </code></pre>
  
  <p>However, when setting </p>
  
  <pre><code>              e.Cancel = true;
  </code></pre>
  
  <p>I get the default message "Invalid Value". </p>
  
  <p>If i use </p>
  
  <pre><code>       gridview1.SetColumnError(m_imixGridView.Columns["MyColumn"], "ColumnSum must be &lt;= 100", DevExpress.XtraEditors.DXErrorProvider.ErrorType.Critical);
  </code></pre>
  
  <p>only, the error message is correct but if i click outside the focus is lost. </p>
  
  <p>I've seen that there are multiple methods for validating rows but didn't find a solution that will suit best in this case. </p>
  
  <p>Is it possible to disable 'unfocus' on a cell if the validation fails?</p>
  
  <p>Thanks a lot!</p>