'Display a SelectField whose options are the changeset_revision strings of all download-able revisions of this repository.'

def get_value(self, trans, grid, repository):

    select_field = grids_util.build_changeset_revision_select_field(trans, repository, downloadable=True)
    if (len(select_field.options) > 1):
        return select_field.get_html()
    elif (len(select_field.options) == 1):
        return select_field.options[0][0]
    return ''
