動畫演示

class AnimationDemo : Fragment() {

    override val root=group {
        val circle = Circle(200.0, 200.0, 10.0)
        class AniTimer: AnimationTimer(){
            var lastTime=0L
            var step=1
            override fun handle(now: Long) {
                if((now-lastTime)> 10000000){
                    lastTime=now
                }else{
                    return
                }
                if (circle.radius > 200 || circle.radius < 0) {
                    step *= -1
                }
                circle.radius = circle.radius + step
            }
        }
        class ColorChanger: AnimationTimer(){
            var lastTime=0L
            var red = 10
            var green = 10
            var blue = 60
            var direction=1
            override fun handle(now: Long) {
                if((now-lastTime)> 10000000){
                    lastTime=now
                }else{
                    return
                }
                circle.fill = Color.rgb(red, green, blue)
                if (red > 254 || red < 1) {
                    direction *= -1
                    blue += 2
                    green += 10
                }
                red += direction
            }
        }
        add(circle)

        ColorChanger().start()
        AniTimer().start()
    }
}