MVVM_01.groovy

<window apply="PersonComposer">
    <grid> 
        <rows>
            <row> <textbox id="txtFirstName"/> </row>
            <row> <textbox id="txtLastName"/>  </row>
            <row> <textbox id="txtFullName"/>  </row>
            <row>
                <hbox id="boxDialog">
                    <button>Save</button>
                    <button>Cancel</button>
                </hbox>
            </row>
        </rows>
    </grid>
</window>


class PersonComposer {

    def viewModel // MyViewModel

    // handler
    def onClick_btnSave(e) {
        def person = viewModel.person
        Person.withTransaction {
            person.save()
        }
    }

}

/*
    page-scoped
*/
class PersonViewModel {

    def binder

    List<Person> personList
    Person person

    static binding = {
        txtFirstName value:"firstName"
        txtLastName  value:"lastName"
        txtFullName  value: fullname
        boxDialog.$("> button") {
            disabled = disable
        }
        txtDayRemain style: dayRemain
    }

    def fullname = [
        forward: { "${person.firstName} ${person.lastName}" },    
        reverse: { fullname -> (person.firstName, person.lastName) = fullname.split(' ') }
    ]

    def dayRemain = {
        if (person.dayRemains < 10)
            "red"
        else
            "black"
    }
    
}