Barchart with Wicket and pure HTML

I needed to display the tweets per day for my date filter @

I tried the jfreechart approach but I didn’t like to have a generated image with an imagemap although it worked and looks nicely.

So here you have the html, css and java snippet necessary to do the same in pure html. Please comment if something is wrong (I had to edit the working code to remove the unnecessary solrJ stuff that I had within that component).


<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
<html xmlns="" xml:lang="en" lang="en"
        <title>[Panel Test]</title>
               <div class="main-bar-chart">
               <div class="bar-chart">
                    <div wicket:id="items">
                        <a wicket:id="itemLink">
                            <span wicket:id="itemLabel">[Text]</span>
                            <div wicket:id="itemSpan"/>


.date-filter .main-bar-chart {
    background: #f2f2f2 url('../img/bottom-line.png') bottom left repeat-x;
    padding: 10px;
    width: 610px;
    height: 100px;
.date-filter-label {
    padding-bottom: 10px;
.date-filter .bar-chart, .main-bar-chart .gray  { color: gray; }

.date-filter .bar-chart .item {
    padding-left: 10px;
    float: left;

.date-filter .bar-chart .item span  {
    font-size: 12px;

.date-filter .bar-chart .item .item-span {
    background-repeat: repeat-y;
background-image: url('../img/bar-min.png');


     private List<Object[]> entryList = new ArrayList<Object[]>();
    private long max = 1;

    public JSDateFilter(String id) {

        ListView items = new ListView("items", entryList) {

            public void populateItem(final ListItem item) {
                float zoomer = MAX_HEIGHT_IN_PX / max;
                final Object[] entry = (Object[]) item.getModelObject();
                String strValue = (String) entry[0];
                Integer count = (Integer) entry[1];
                Label bar = new Label("itemSpan");

                AttributeAppender app = new AttributeAppender("title", new Model(count + " entries"), " ");
                bar.add(app).add(new AttributeAppender("style", new Model("height:" + (int) (zoomer * count) + "px"), " "));
                AjaxFallbackLink link = new AjaxFallbackLink("itemLink") {

                    public void onClick(AjaxRequestTarget target) {
                Label label = new Label("itemLabel", strValue);
                if (count == 0) {
                    link.add(new AttributeAppender("class", new Model("gray"), " "));

//                if (selected)
//                    link.add(new AttributeAppender("class", new Model("filter-rm"), " "));
//                else
//                    link.add(new AttributeAppender("class", new Model("filter-add"), " "));



    public void update(Map<String, Integer> map) {
        max = 1;
        for (Entry<String, Integer> e : map.entrySet()) {
            entryList.add(new Object[]{e.getKey(), e.getValue()});
            if (e.getValue() > max)
                max = e.getValue();

You can use this code in your wicket page via the following snippet in the html:

<div wicket:id="dateFilter">[dateFilter]</div>

and add(new DateFilter(“dateFilter”)) in the Java part. The bar image is available here.

Test All Browsers Under Almost One Operating System

For professional website development it is necessary to test the application under the major browsers. I will not decide which browsers the major ones are. Instead you can “install” all browser at one time under the latest Ubuntu:

  1. If you have Ubuntu you already have access to Firefox, Konqueror and Opera
  2. Now install VirtualBox and  a Windows of you choice (installation of Novell Silverlight fails under my ubuntu version :-()
    1. Now you can install Microsoft Silverlight under Windows
    2. Go to xenocode then you can install InternetExplorer 6,7 and 8. Plus the Mac Os browser Safari
      The cool thing about xenocode is that you can have several different versions of IE installed (and even all the others)

View the results in the picture below:


From left to right: Firefox 3, Opera 9.6, Konqueror 4.2, IE 7, IE 8 and Safari 3

So, even if the side is only a static one like my timefinder side not all browser display it correctly (konqueror fails …)

Have fun to try your application under all the funky browsers out there …