Understanding Timelines

Question

I am learning JavaFX, have been through a few tutorials (all of which worked, thats something new in Java :) ) and have come to the conclusion that 'I like it'.
I am still at the beginning really, so the test pieces I am doing do not really have a purpose other than learning JavaFX.
The part I am stuck on at the moment is using Timeline. Each example seems to use a piece of magic dust to bind a timer event to something in the scene. I am a bit short of magic dust right now.
Lets say that I want to display a different word each time we get the timer event. I believe I have to bind a variable inside my scene to the timer. (ok, so I have already tried binding everywhere now). Nothing happens of cause, so what are the rules here? The JavaFX master index doesn't give any clues and all of the examples around do the same thing, assume you know what to bind to what in order to get a timer event to act on your scene.
You do not need to use my example here to explain it if you already have a nice neat example, but if you use something like
x => newX tween Interpolator.EASEBOTH;
I shall be cross with you.
Here is my diddy little example:
* Main.fx
* Created on 04-Feb-2010, 15:52:22
package textstuff;
import javafx.stage.Stage;
import javafx.scene.Scene;
import javafx.scene.text.Text;
import javafx.scene.text.Font;
import javafx.animation.Timeline;
import javafx.animation.KeyFrame;
import javafx.animation.Interpolator;
* @author robert
var arStrings = ["one ", "two ", "three ", "four "];
var iCount = 0;
//My timer, every 5 seconds iCount is incremented, the word onscreen should change
// iCount is incremented because I can see in the console output
var timer = Timeline {
     repeatCount: Timeline.INDEFINITE
     keyFrames : [
          KeyFrame {
               time : 5s
               canSkip : true
action: function () {
++iCount;
if(iCount > 3)
iCount = 0;
println(iCount);
//I had to use timer.play() though tutorials don't always use it.( Magic dust again )
timer.play();
Stage {
title: "Application title"
//I have tried this in various places, but can not update my scene
// var ar = bind iCount;
scene: Scene {
//I have tried this in various places, but can not update my scene
var ar = bind iCount;
width: 250
height: 80
content: [
Text {
font : Font {
size : 24
x: 10
y: 30
//this ought to change but it doesn't
content: "{arStrings[ar]}"
I would rather have an explanation than an auto changing text block, but just do your best, cheers
Edited by: rassler on Feb 4, 2010 9:41 AM

Answer 1

General advice: use the CODE button above the textarea to avoid issues like interpreting the asterisk as bold mark...
It just need a bind at the right place... :)
Stage {
    title: "Application title"
    scene: Scene {
        width: 250
        height: 80
        content: [
            Text {
                font : Font {
                    size : 24
                x: 10
                y: 30
                content: bind arStrings[iCount]
}There, bind acts on arStrings (defining it with a 'def' here would be more efficient) and on iCount.