The default implementation returns a string containing v printed in the standard way. Override this function in in a subclass if you want a specialized spin box, handling something else than integers. This function need not be concerned with prefix or suffix or special-value text, the QSpinBox handles that automatically. This method gets called by QRangeControl whenever the range has changed. It adjusts the default validator and updates the display.
Handles resize events for the spin box.
Reimplemented from QWidget. The prefix is prepended to the start of the displayed value. Typical use is to indicate the unit of measurement to the user. To turn off the prefix display, call this function with 0 or an empty string as parameter. The default is no prefix.