clamp_page
Description:
Updates the value property to ensure that the range between lower and upper is in the current page.
The current page goes from `value` to `value` + `page-size`. If the range is larger than the page size, then only the start of it will be in the current page.
A [signal@Gtk.Adjustment:GtkAdjustment:value-changed] signal will be emitted if the value is changed.
Parameters:
| this |
a `GtkAdjustment` |
| lower |
the lower value |
| upper |
the upper value |