GtkAdjustment::set_value
void set_value(double value);
This method sets the adjustment value to a
new level. It doesn't work where that value has already been set
by a widget or widgets; widget settings always take precedence over
manual settings. Where it is allowed, it causes a
"value-changed" signal
to be emitted, if the value is within the adjustment range.
Adjustable widgets generally have their own wrapper method for setting
the adjustment value, which should be used in preference where it
exists.