This works now, I tested it in the current JForex 3.2.21
IChart chart = context.getChart(Instrument.EURUSD);
IIndicator adx = indicators.getIndicator("ADX");
for (int i = 0; i < adx.getIndicatorInfo().getNumberOfOutputs(); i++) {
OutputParameterInfo output = adx.getOutputParameterInfo(i);
output.setColor(Color.red);
output.setColor2(Color.yellow);
}
chart.add(adx, new Object[]{14}, null, // color array value must be null here
new DrawingStyle[]{DrawingStyle.LINE}, new int[]{1});
You have to set the color array to null, otherwise the color will be always overwritten by the chart.add function.