public void commandAction(Command c, Displayable d) {
        // Help command displays Help Form
         if (c == CMD_HELP) {
            HelpForm h = new HelpForm(this.midlet, this, "edit_number");
            this.midlet.display.setCurrent(h);
        }

        // exit command goes back to Main Menu
        if (c == CMD_EXIT) {
            this.midlet.display.setCurrent(this.midlet.mainMenu);
        }

        // save command stores new number in config or display errors.
        if (c == CMD_SAVE) {
            Alert alert;
            if (config.set("server_number", numberField.getString())) {
                String saved = config.get("server_number");
                alert = new Alert ("Succès !", "Le nouveau numéro a été enregistré: " + saved, null, AlertType.CONFIRMATION);
            } else {
                alert = new Alert ("FAIL!", "fail to save", null, AlertType.WARNING);
                alert.setTimeout(Alert.FOREVER);
            }
            this.midlet.display.setCurrent (alert, this);
        }
    }