private Widget createCostField() {
    costField =
        new NumberField() {
          @Override
          public boolean validate() {
            if (splitPurchaseGrid != null) {
              splitPurchaseGrid.setTotalCost(getCost());
            }

            return super.validate();
          }
        };
    costField.setFieldLabel("Cost");
    costField.setAllowDecimals(true);
    costField.setAllowNegative(true);
    costField.setAllowBlank(false);

    return costField;
  }
  protected void onRender(Element parent, int index) {
    super.onRender(parent, index);
    setLayout(new FitLayout());
    setId("network-dhcp-nat");
    FormData formData = new FormData();
    formData.setWidth(250);

    m_formPanel = new FormPanel();
    m_formPanel.setFrame(false);
    m_formPanel.setBodyBorder(false);
    m_formPanel.setHeaderVisible(false);
    m_formPanel.setLayout(new FlowLayout());
    m_formPanel.setStyleAttribute("min-width", "775px");
    m_formPanel.setStyleAttribute("padding-left", "30px");

    FieldSet fieldSet = new FieldSet();
    FormLayout layoutAccount = new FormLayout();
    layoutAccount.setLabelWidth(Constants.LABEL_WIDTH_FORM);
    fieldSet.setLayout(layoutAccount);
    fieldSet.setBorders(false);

    //
    // Tool Tip Box
    //
    toolTipField.setText(defaultToolTip);
    fieldSet.add(toolTipField);

    //
    // Router Mode
    //
    m_modeCombo = new SimpleComboBox<String>();
    m_modeCombo.setName("comboMode");
    m_modeCombo.setFieldLabel(MSGS.netRouterMode());
    m_modeCombo.setEditable(false);
    m_modeCombo.setTypeAhead(true);
    m_modeCombo.setTriggerAction(TriggerAction.ALL);
    for (GwtNetRouterMode mode : GwtNetRouterMode.values()) {
      m_modeCombo.add(MessageUtils.get(mode.name()));
    }
    m_modeCombo.setSimpleValue(MessageUtils.get(GwtNetRouterMode.netRouterDchpNat.name()));
    m_modeCombo.setValidator(
        new Validator() {
          public String validate(Field<?> field, String value) {
            if (m_tcpIpConfigTab.isDhcp()
                && !value.equals(MessageUtils.get(GwtNetRouterMode.netRouterOff.toString()))) {
              return MSGS.netRouterConfiguredForDhcpError();
            }

            return null;
          }
        });
    m_modeCombo.addSelectionChangedListener(
        new SelectionChangedListener<SimpleComboValue<String>>() {
          @Override
          public void selectionChanged(SelectionChangedEvent<SimpleComboValue<String>> se) {
            refreshForm();
          }
        });
    m_modeCombo.addListener(Events.OnMouseOver, new MouseOverListener(MSGS.netRouterToolTipMode()));
    m_modeCombo.addStyleName("kura-combobox");
    m_modeCombo.addPlugin(m_dirtyPlugin);
    fieldSet.add(m_modeCombo, formData);

    //
    // DHCP Beginning Address
    //
    m_dhcpBeginAddressField = new TextField<String>();
    m_dhcpBeginAddressField.setAllowBlank(true);
    m_dhcpBeginAddressField.setName("dhcpBeginAddress");
    m_dhcpBeginAddressField.setFieldLabel(MSGS.netRouterDhcpBeginningAddress());
    m_dhcpBeginAddressField.setRegex(IPV4_REGEX);
    m_dhcpBeginAddressField.getMessages().setRegexText(MSGS.netIPv4InvalidAddress());
    m_dhcpBeginAddressField.addPlugin(m_dirtyPlugin);
    m_dhcpBeginAddressField.setStyleAttribute("margin-top", Constants.LABEL_MARGIN_TOP_SEPARATOR);
    m_dhcpBeginAddressField.addStyleName("kura-textfield");
    m_dhcpBeginAddressField.addListener(
        Events.OnMouseOver, new MouseOverListener(MSGS.netRouterToolTipDhcpBeginAddr()));
    fieldSet.add(m_dhcpBeginAddressField, formData);

    //
    // DHCP Ending Address
    //
    m_dhcpEndAddressField = new TextField<String>();
    m_dhcpEndAddressField.setAllowBlank(true);
    m_dhcpEndAddressField.setName("dhcpEndAddress");
    m_dhcpEndAddressField.setFieldLabel(MSGS.netRouterDhcpEndingAddress());
    m_dhcpEndAddressField.setRegex(IPV4_REGEX);
    m_dhcpEndAddressField.getMessages().setRegexText(MSGS.netIPv4InvalidAddress());
    m_dhcpEndAddressField.addListener(
        Events.OnMouseOver, new MouseOverListener(MSGS.netRouterToolTipDhcpEndAddr()));
    m_dhcpEndAddressField.addStyleName("kura-textfield");
    ;
    m_dhcpEndAddressField.addPlugin(m_dirtyPlugin);
    fieldSet.add(m_dhcpEndAddressField, formData);

    //
    // DHCP Subnet Mask
    //
    m_dhcpSubnetMaskField = new TextField<String>();
    m_dhcpSubnetMaskField.setAllowBlank(true);
    m_dhcpSubnetMaskField.setName("dhcpSubnetMask");
    m_dhcpSubnetMaskField.setFieldLabel(MSGS.netRouterDhcpSubnetMask());
    m_dhcpSubnetMaskField.setRegex(IPV4_REGEX);
    m_dhcpSubnetMaskField.addListener(
        Events.OnMouseOver, new MouseOverListener(MSGS.netRouterToolTipDhcpSubnet()));
    m_dhcpSubnetMaskField.getMessages().setRegexText(MSGS.netIPv4InvalidAddress());
    m_dhcpSubnetMaskField.addStyleName("kura-textfield");
    m_dhcpSubnetMaskField.addPlugin(m_dirtyPlugin);
    fieldSet.add(m_dhcpSubnetMaskField, formData);

    //
    // DHCP Default Lease
    //
    m_dhcpLeaseDefaultField = new NumberField();
    m_dhcpLeaseDefaultField.setPropertyEditorType(Integer.class);
    m_dhcpLeaseDefaultField.setAllowDecimals(false);
    m_dhcpLeaseDefaultField.setAllowNegative(false);
    m_dhcpLeaseDefaultField.setMaxValue(Integer.MAX_VALUE);
    m_dhcpLeaseDefaultField.setAllowBlank(true);
    m_dhcpLeaseDefaultField.setName("dhcpDefaultLease");
    m_dhcpLeaseDefaultField.setFieldLabel(MSGS.netRouterDhcpDefaultLease());
    m_dhcpLeaseDefaultField.addListener(
        Events.OnMouseOver, new MouseOverListener(MSGS.netRouterToolTipDhcpDefaultLeaseTime()));
    m_dhcpLeaseDefaultField.addPlugin(m_dirtyPlugin);
    fieldSet.add(m_dhcpLeaseDefaultField, formData);

    //
    // DHCP Max Lease
    //
    m_dhcpLeaseMaxField = new NumberField();
    m_dhcpLeaseMaxField.setPropertyEditorType(Integer.class);
    m_dhcpLeaseMaxField.setAllowDecimals(false);
    m_dhcpLeaseMaxField.setAllowNegative(false);
    m_dhcpLeaseMaxField.setMaxValue(Integer.MAX_VALUE);
    m_dhcpLeaseMaxField.setAllowBlank(true);
    m_dhcpLeaseMaxField.setName("dhcpMaxLease");
    m_dhcpLeaseMaxField.setFieldLabel(MSGS.netRouterDhcpMaxLease());
    m_dhcpLeaseMaxField.addListener(
        Events.OnMouseOver, new MouseOverListener(MSGS.netRouterToolTipDhcpMaxLeaseTime()));
    m_dhcpLeaseMaxField.addPlugin(m_dirtyPlugin);
    fieldSet.add(m_dhcpLeaseMaxField, formData);

    //
    // Pass DNS
    //
    m_passDnsRadioTrue = new Radio();
    m_passDnsRadioTrue.setBoxLabel(MSGS.trueLabel());
    m_passDnsRadioTrue.setItemId("true");

    m_passDnsRadioFalse = new Radio();
    m_passDnsRadioFalse.setBoxLabel(MSGS.falseLabel());
    m_passDnsRadioFalse.setItemId("false");

    m_passDnsRadioGroup = new RadioGroup();
    m_passDnsRadioGroup.setName("dhcpPassDns");
    m_passDnsRadioGroup.setFieldLabel(MSGS.netRouterPassDns());
    m_passDnsRadioGroup.add(m_passDnsRadioTrue);
    m_passDnsRadioGroup.add(m_passDnsRadioFalse);
    m_passDnsRadioGroup.addPlugin(m_dirtyPlugin);
    m_passDnsRadioGroup.addListener(
        Events.OnMouseOver, new MouseOverListener(MSGS.netRouterToolTipPassDns()));
    fieldSet.add(m_passDnsRadioGroup, formData);

    m_formPanel.add(fieldSet);
    add(m_formPanel);
    setScrollMode(Scroll.AUTO);
    m_initialized = true;
  }