GtkHScale a horizontal slider widget for selecting a value from a range. The #GtkHScale widget is used to allow the user to select a value using a horizontal slider. A #GtkAdjustment is used to set the initial value, the lower and upper bounds, and the step and page increments. The position to show the current value, and the number of decimal places shown can be set using the parent #GtkScale class's functions. The #GtkHScale-struct struct contains private data only, and should be accessed using the functions below. Creates a new #GtkHScale. @adjustment: the #GtkAdjustment which sets the range of the scale. @Returns: a new #GtkHScale.