Your code must then interpret the spin box value of -1 as the user requesting automatic margin width. Neither prefix nor suffix, if set, are added to the special-value text when displayed. To turn off the special-value text display, call this function with an empty string as parameter. The default is no special-value text, i.e. the numeric value is shown as usual. The suffix is appended to the end of the displayed value.
Typical use is to indicate the unit of measurement to the user.
To turn off the suffix display, call this function with an empty string as parameter. The default is no suffix. Sets the validator to v. The validator controls what keyboard input is accepted when the user is editing in the value field. The default is to use a suitable QIntValidator .