To provide your chart with additionnal tooltips and image map +information you have to provide an additional Java class or enhance an +existing one like the one below. In this tutorial we will add some +methods to the datasetproducer class which had been introduced at the +beginning of this tutorial.
++
...+
public String generateLink(Object data, int series, Object category) {
return seriesNames[series];
}
public String generateToolTip(CategoryDataset arg0, int series, int arg2) {
return seriesNames[series];
}
...
As you can see it is very easy to implement a class that produces +image map and tooltips information. First of all it has to implement the +interfaces CategoryItemLinkGenerator and CategoryToolTipGenerator +(as it produces a CategoryDataset). For other data types refer to the cewolf java api.
+To let your class produce links and tooltips for the chart image you +have to change the <cewolf:img> tag as follows:
++
<cewolf:img chartid="line" renderer="cewolf" width="400" height="300">+
<cewolf:map id="pageViews"/>
</cewolf:img>
Reload your page and you will see tooltips and links on data points. +Internet Explorer browsers are handled slightly different as others as +they are able to render a tooltip based on the alt attribute +inside an image map. All other browser need the overlib.js for this. +Cewolf tries to determine the used browser and renders a correct page +transparently.
+For further information on using Cewolf refer to the Tag Library Reference and the Cewolf JavaDoc.
+If you want to see more examples of how to implement catchy charts +in your webapp, you should deploy the example webapp (downloadable from +the Cewolf home +page and have a look at its sourcecode.
+