There is a mark column in the ultragrid,and it requires a postive data, when user click the add button, the ultraGrid add a new row,
and the mark cell display a red icon(indicate user should input a valid data ) by default,when input a negative the red icon show still,
if input a positive,the red icon disappear at once, if the data is invalid and you can not move out from this cell . (in winform)

How to handle it?

thanks