I'm having a problem using a validation rule in a data grid:
I want to use a ValidationRule on a DataGridComboBoxColumn, I used this example
for guidance, in particular the BindingGroup stuff.
This works to an extent but seems very broken. The ValidatioRule doesn't fire as soon as the combo box selection changes, instead it fires only when I change the selection then click on another row in the DataGrid. I really need it to fire as soon as I have changed the selection of the combo box.
I've tried messing with the validation step but to no avail, can anybody help?
Thanks in advance!