resizableIcons

If you want the icon size to be user definable, then create an IntProperty for the preferred size. And use it like so :

val iconSizeUserPreference : IntProperty = ...
val myIcons = icons{ ... } // Build metadata for many sizes
val myResizableIcons = myIcons.resizable( iconSizeUserPreference )
val myImageView = ImageView(rmyResizableIcons[ "document-save" ])