Zk Charts Change color of crosshair lines in zk

Q:How can I change the color of the crosshair lines? Only found a boolean flag in Tooltip class for switching crosshairs on/off.

Ans:The color of the crosshair lines can be customized by ```setCrosshairs(List)``` in Tooltip .

http://www.zkoss.org/javadoc/latest/zkcharts/org/zkoss/chart/Tooltip.html.

For example:

    Tooltip tooltip = chart.getTooltip();

    // create a list to store the style maps
    List<Map<String, String>> crosshairsStyle = new LinkedList<Map<String, String>>();

    // add the first map to customize x axis crosshair style 
    Map<String, String> xStyle = new LinkedHashMap<String, String>();
    xStyle.put("color", "#f39c12");
    crosshairsStyle.add(xStyle);

    // add the second map to customize y axis crosshair style 
    Map<String, String> yStyle = new LinkedHashMap<String, String>();
    yStyle.put("color", "#27ae60");
    yStyle.put("dashStyle", "dash");
    yStyle.put("width", "2");
    crosshairsStyle.add(yStyle);

    tooltip.setCrosshairs(crosshairsStyle);