QlineEdit -- how to enter single value -- with no spaces

QlineEdit -- how to enter single value -- with no spaces

I have made an editor in which i have to enter a Hex or decimal value in
each field. Here the field i am using is QlineEdit.
Now requirement is that each Qlineedit box accept only one value without
spaces. Then i can read this text value & convert it directly from string
to decimal.
Is it possible to make QlineEdit to accept only one value without spaces ?
Boxes in below figure are QlineEdit.
I do not want to use combo box here.