JAVAFX - Control candleStick chart with a slider

Question

I was trying to use old-known JAVA-FX candlestick chart, and having some trouble with it. When ever I try to re size my chart with a slider I have attached to it, for some reason the candles begin to grow bigger(thicker) or turn really small(thinner).

my sliderX is a slider with a data information, set min value as the minimum day(1), and max value as the maximum day.

I have the following code as the listener to my slider:

    sliderX.valueProperty().addListener(new ChangeListener<Number>() {
        public void changed(ObservableValue<? extends Number> ov,
            Number oldValue, Number newValue) {
                xAxis.setLowerBound(newValue.doubleValue());
                xAxis.setUpperBound(newValue.doubleValue() + 100);
                xAxis.setTickMarkVisible(true);
                chart.updateAxisRange();
        }

The idea was to see 100 days forward each time, and moving across the data with +100 interval. so in the beginning the chart will show 0-100 prices, and with one click of the slider to the left he will show 1-101 prices and etc.

I am clearly missing something but haven`t seen any normal explanation about this issue, maybe you can direct me to a tutorial/doc I can read and learn from. Not looking for a magic solution(but one can be good), but more a place to learn what was my misconception in this area.

Thanks.

Answer 1

Over the last couple of days I've been working on a similar issue and I found a solution that might better help you adapt your code in the following link: https://community.oracle.com/message/11143490#11143490

I think the issue is that you are using the newValue on both lower and upper bounds which seems to adjust the axis viewable area rather than pan/scroll side to side.

You could try implementing it like this:

sliderX.valueProperty().addListener(new ChangeListener<Number>() {
    public void changed(ObservableValue<? extends Number> ov, Number oldValue, Number newValue) {

            Delta = newValue.doubleValue() - oldValue.doubleValue(); 

            xAxis.setLowerBound(xAxis.getLowerBound() + Delta);
            xAxis.setUpperBound(xAxis.getUpperBound() + Delta);
            xAxis.setTickMarkVisible(true);
            chart.updateAxisRange();
    }
}

I have used a similar version of this code successfully on a JavaFX8 candlestick chart implementation for panning/scrolling (using a drag event rather than a slider but the math should remain the same)