Is there a way to set a Checkbox with something like AllowBlank="false"? I'd like my page validation to not let the form submit if the checkbox is not checked. Is there an attribute for this in ext.net? I know I can handle it on the back-end but just wanted to see if there's some easy way to do it I'm missing.

I use the following to check validation on the front end and I'd like it to catch an unchecked checkbox:

                <ext:Button ID="btnSubmit" runat="server" Text="Submit Nomination">
                    <Listeners>
                        <Click Handler="if (#{pnlNominationForm}.getForm().isValid()) {App.direct.submitNomination();}else{Ext.Msg.show({icon: Ext.MessageBox.ERROR, msg: 'Please check the fields and try again!', buttons:Ext.Msg.OK});}" />
                    </Listeners>
                </ext:Button>