select/unselect 1 row on xbrowse

[Silvio.Falconi]

On Xbrowse, Select block of rows Shift-Click and toggle selection by Ctrl-Click.

But if I wish make the same from a button wich command I must call to select /unselect a row of xbrowse ?

I tried with
DEFINE BUTTON OF oBar RESOURCE "LOOK_SEL" ACTION oBrw:SelectRow(1)
DEFINE BUTTON OF oBar RESOURCE "LOOK_DESEL" ACTION oBrw:SelectRow(2)

but not run