''

def scan_tasks(self, ignore_shutdown=False):

    for row in self.liststore:
        if (len(self.workers.keys()) >= self.app.profile['concurr-download']):
            break
        if (row[STATE_COL] == State.WAITING):
            self.start_worker(row)
    if ((not self.shutdown_button.get_active()) or ignore_shutdown):
        return
    for row in self.liststore:
        if (row[STATE_COL] not in (State.PAUSED, State.FINISHED, State.CANCELED)):
            return
    self.shutdown.shutdown()
