The QRangeControl class provides an integer value within a range. ... QRangeControl  ( int minValue, int maxValue, int lineStep, int pageStep, int value )  . ... void  setValue  ( int )  . ... virtual void  valueChange  ()  . ... The three virtual functions valueChange (), rangeChange () and stepChange () can be reimplemented in a subclass to detect range control changes. ... Sets the range control value to value. ... This virtual function is called whenever the range control step value changes. ...