7guis counter

Counter.groovy

import javafx.geometry.Insets
import static groovyx.javafx.GroovyFX.start

start {
    stage(title: 'Counter', show: true, onHidden:{e -> System.exit(0)}) {
        scene {
            hbox(spacing:10, padding:new Insets(10)) {
                textField(id: 'count', editable: false, prefColumnCount: 10, text:'0')
                button('count', onAction:{e -> count.text = (count.text as Integer) + 1})
            }
        }
    }
}

CounterModel.groovy

// Or, with binding:

import javafx.geometry.Insets
import groovyx.javafx.beans.FXBindable
import static groovyx.javafx.GroovyFX.start

class Model {
    @FXBindable String clicksStr = "0"
    private int clicks = 0

    def onClick = {
        clicksStr = "${++clicks}"
    }
}

start {
    def model = new Model()
    stage(title: 'Counter', show: true, onHidden:{e -> System.exit(0)}) {
        scene {
            hbox(spacing:10, padding:new Insets(10)) {
                textField(id: 'count', text:bind(model.clicksStrProperty), editable: false, prefColumnCount: 10)
                button('count', onAction:model.onClick, focused: true)
            }
        }
    }
}