Silverlight Datagrid Validation on End Edit - validation

Question

I need to do validation on a grid column. all the cells in that column are blank. the user needs to input data and then i need to validate it.
I have at the moment the validation on the cells working but it works on Begin Edit event instead of the end edit event. which is pointless as the validation needs to check if they have entered information.
How can i get the validation to validate on the end edit Event?
Thank in advance for your help
Niven.
Code:
private string _reference;
public string Reference
{
get
{
return _reference;
}
set
{
_reference = value;
ChangeValue("Reference");
}
}
public event PropertyChangedEventHandler PropertyChanged;
public void ChangeValue(string propName)
{
if (PropertyChanged != null)
{
PropertyChanged(this, new PropertyChangedEventArgs(propName));
}
}
public string this[string columnName]
{
get
{
string msg = null;
if (columnName == "Reference")
{
if (Reference == "" && ValidateItem)
{
msg = "Reference is Required. Please Enter a Reference";
}
}
return msg;
}
}
string err;
public string Error
{
get { return err; }
}

Answer 1

I've just solved this behavior with the custom code below. I didn't have time to test all scenarios yet, but I'm pretty confident with the results.
public class ExtendedDataGrid : DataGrid {
private ValidationSummary _validationSummary = null;
private bool _validationFilterBehaviorApplied = false;
private bool _validationFilterBehaviorRestored = false;
public ExtendedDataGrid() { }
public override void OnApplyTemplate() {
base.OnApplyTemplate();
this._validationSummary = (ValidationSummary)this.GetTemplateChild("ValidationSummary");
}
protected override void OnBeginningEdit(DataGridBeginningEditEventArgs e) {
if (!_validationFilterBehaviorApplied) {
_validationSummary.Filter = ValidationSummaryFilters.None;
_validationFilterBehaviorApplied = true;
}
base.OnBeginningEdit(e);
}
protected override void OnRowEditEnding(DataGridRowEditEndingEventArgs e) {
if (_validationFilterBehaviorApplied && !_validationFilterBehaviorRestored) {
_validationSummary.Filter = ValidationSummaryFilters.All;
_validationFilterBehaviorRestored = true;
}
base.OnRowEditEnding(e);
}
protected override void OnRowEditEnded(DataGridRowEditEndedEventArgs e) {
_validationFilterBehaviorApplied = false;
_validationFilterBehaviorRestored = false;
base.OnRowEditEnded(e);
}
}