Gtk.TreeStore.prototype.insert_after

function insert_after(parent:Gtk.TreeIter, sibling:Gtk.TreeIter):void {
    // Gjs wrapper for gtk_tree_store_insert_after()
}

Inserts a new row after sibling. If sibling is null, then the row will be prepended to parent 's children. If parent and sibling are null, then the row will be prepended to the toplevel. If both sibling and parent are set, then parent must be the parent of sibling. When sibling is set, parent is optional.

iter will be changed to point to this new row. The row will be empty after this function is called. To fill in values, you need to call Gtk.set or Gtk.set_value.