{curl 7.0 applet}

{let r:Fraction, g:Fraction, b:Fraction}
{let f:Fill =
    {Fill width = 1cm,
        height = 1cm,
        background = "black"}
}
{let cb:CommandButton =
    {CommandButton
        label = "change size and color for 5.5 seconds...",
        {on Action do
            {f.animate
                interval = 0.1s,
                repeat = 55,
                {on TimerEvent do
                    set r = (r + 0.05) mod 1.0
                    set g = (g + 0.02) mod 1.0
                    set b = (b + 0.03) mod 1.0
                    set f.background = {Color.from-rgb r, g, b}
                    set f.width = 4cm * r
                    set f.height = 4cm * g
                }
            }
        }
    }
}
{VBox
    {HBox height = 5cm, width = 5cm, f},
    {HBox cb}
}