Note that only the Cell Validating event can keep the editor active,when the validation fails and it does not allow the user to exit the cell until a valid value is filled.However, pressing the Esc key in this situation will revert the initial value of the cell and it will close the editor. The Row Validating event has a slightly different behavior. The hanging up problem I couldn't reproduce so I guess it has to do with the code of your executed buttons there.
By asynchronous validation I mean that Rad Grid View can save a value in its collection and from somewhere (server side usually) to receive a message that this value doesn’t pass some business requirements.
Note: When i debug code and insert breakpoints on cell Validating event and button.
Cell Validating Dim column As Grid View Data Column = Try Cast(e. Row Is Grid View Data Row Info And Also column Is Not Nothing And Also column.
This means that Rad Grid View will fire all events related to editing and validation logic (cell/row Validating, cell/row Validated, cell/row Edit Ended) and will leave edit mode. Keep in mind that Rad Grid View will not scroll wrong items (cells) into view, only if corresponding UI elements (cells and rows) are visible (or become visible) they will update their validation status.
When such an error message occurs then Rad Grid View will show the error accordingly. For Silverlight async validation will be provided by INotify Data Error Info interface.