get_preferred_width

Description:

public virtual void get_preferred_width (Container container, float for_height, out float min_width_p, out float nat_width_p)

Computes the minimum and natural widths of the container according to this.

this	a LayoutManager
container	the Container using this
for_height	the height for which the width should be computed, or -1
min_width_p	return location for the minimum width of the layout, or `null`
nat_width_p	return location for the natural width of the layout, or `null`