Why does the following not trigger the Validate event when a letter is typed into the TextEdit? If will trigger the event only when focus is lost.
<dxe:TextEdit EditValue="{Binding MyName}" ValidateOnTextInput="True" ValidateOnEnterKeyPressed="False" />
I've not used that control, but try this:
<dxe:TextEdit EditValue="{Binding MyName, UpdateSourceTrigger=PropertyChanged}"
ValidateOnTextInput="True" ValidateOnEnterKeyPressed="False" />
You can find out more from the Binding.UpdateSourceTrigger
Property page on MSDN.