EclipseCon Submissions - Last Chance to Propose a Talk

Oisín Hurley is one of the smartest, funniest and best looking people in the Eclipse community*  So when he says jump, I jump.

That's right it is the last day to get your EclipseCon submission for a talk in.  If you have been doing anything interesting with BIRT that you would like to share with the Eclipse community, we would love to hear about it.  There are lots of opportunities to present at different lengths.

Head on over to the EclipseCon submission site and make a proposal about how you are using BIRT.


*And totally immune to blatant attempts at flattery.

BIRT Plugins at Google Code

Blackboard, Inc. develops solutions for the K-12 school, college campus, workplace, and community that increase the impact of education by transforming the experience of education. Blackboard has chosen BIRT as its reporting and business intelligence tool.  

Over the last two years I have been lucky to work with Blackboard on their BIRT integration.  Working with their product and developers we have been able to enhance their core product with reports.  Each Blackboard report tells a story that can help their clients better perform their jobs.  

One of BIRT's features that was extremely helpful was the ability to customize and extend BIRT to meet Blackboards requirements.  Using the BIRT extension points we added functions and controls to BIRT that improved both the developer and users experience when interacting with BIRT.

Blackboard has agreed to release some of the generic portions of this work back to the BIRT community as open source contributions.  Rather than rolling these contributions into the core product (where it would quickly get lost amidst all the other code) we have created two small open source projects that can be used by the community.  These projects can be used either as fully functional products or as best practice sample code.  

	BIRT Functions	Uses the Aggregate and Script Function extension point to add new functions to the BIRT product.
	BIRT Controls	Uses the ReportItem extension point to create new elements that show up on BIRT reports.
	Innovent Update Site	Hosts an Eclipse Update site for both projects. We will be adding new projects to this site as we finish up the code.

If you are a BIRT developer that just wants to get started you can use the following update link:
  http://innovent.googlecode.com/svn/trunk/update

If you would like to find out a bit more about the projects, please visit the project sites.

• BIRT Functions Plugin
• BIRT Controls Plugin

Thanks go out to thank both BIRT Exchange and the brand spanking new Eclipse Marketplace for providing access to our projects.  It is really great to have a couple of quality channels to publicize our work to the BIRT community.

Also, I want to mention the team that helped to build and get this code open sourced.  Steve Schafer from Innovent Solutions wrote a lot of the code and figured out the inner workings of the ReportItem exension point.  Blackboard had a whole team of people working on reports, in particular thanks to Heather, JoAnna, Michelle, Dan, Joe, Joel, and Manpreet.

Calling Client Side JavaScript from a BIRT Chart

A couple of months ago I detailed a new feature for BIRT charts that allows multiple hyperlinks to be attached to one the supported events. That post is available here.

In this post I will discuss using a BIRT Text element that contains script which executes within the client browser and contains functions that are called from rendered charts.

General Information
BIRT currently supports interactivity on many chart components like chart series, title, axis, and the legend. The components that support interactivity will depend on the type of chart being used. The events are client based events like mouse click, mouse over, key down, etc. Multiple events can be hooked and each is associated with an action. Actions define the behavior that should occur when a specific event happens. The actions available depend on what component the action is defined for and what chart output type is being used. Currently BIRT supports the following Actions.

Hyperlink – Supports multiple hyperlinks, drill through, and linking to bookmarks.
Show Toolip – Supports displaying tooltips. Data available for use in the tooltip will depend on the component.
Highlight – Highlights the selected component. Most often used to highlight specific series or data point.
Toggle Visibility – Toggles the visibility of the selected component. Most often used to change the visibility of a series or data point.
Toggle DataPoint Visibility – Toggles the data point label visibility.
Invoke Script – Invokes client side script.

Additionally if you are using the Chart engine within an SWT, SVG, or Swing based application the engine supports adding a callback action that your code can use to interpret chart events.



Highlight, Toggle Visibility, and Toggle DataPoint Visibility actions are only available when using an SVG output setting.



If you use SVG, and you wish to test the report in the designer remember to set the Enable SVG chart in the Preview preferences for the Report Design Preference entry.



More information on Chart Interactivity is available here. Also see the Chart FAQ for more details.

InvokeScript Example
The follow section details an example of using the invokeScript action on multiple Chart events.

Assume that you have a Chart that displays a set of customers with a series value for each equal to the customer's credit limit.



Suppose you want to display the customer details right below the chart when the mouse is moved over a specific data point. This can be done using the invokeScript action on the mouse over event for the chart series. To do this first create a table below the chart that is bound to the same dataset that the chart is using. You can then nest a table that calls another data set to retrieve customer information. In the attached example this will be the ChartData and CustomerInformation datasets respectively.



By default this will generate a inner table that contains customer information for every customer represented in the chart. Obviously you do not want to display all of these at once, so create a new style in the style editor with only one property overridden – Text Block:Display set to no Display. Apply this new style to both the inner and outer tables.



If you run the report after completing this step all the tables will be generated in the output but none will be displayed. This is different than using the visibility property which will not put the tables in the output. Enter the following bookmarks for the outer and inner tables.

Outer table bookmark expression: "myoutertable";
Inner table bookmark expression: "mytable"+row["CUSTOMERNUMBER"]

This will assign the outer table id to myoutertable and a unique id for each inner table starting with mytable and the customer number for the given inner table appended to it. We can now use these with some client script to turn them on or off.

Add a Text element below the two tables with the following value.


<script>
function clearSel(){
var ot=document.getElementById("myoutertable");
ot.style.display="none";
var intbls=ot.getElementsByTagName("TABLE");
for( jj=0; jj<intbls.length; jj++ ){
intbls[jj].style.display = "none";
}
}
function DisplayCustomer(cat) {
clearSel();
//alert(cat);
document.getElementById("myoutertable").style.display="block"
document.getElementById("mytable"+cat).style.display="block"

}
</script>



Make sure to set the Text type to HTML.

The clearSel function first finds the outer table and then locates every nested table and sets the display style for each to none. The outer table’s display style is also set to none. This will effectively hide both tables.

The DisplayCustomer function first clears all current displayed tables. Next it uses a category passed in from the Chart to find the specific customer inner table and sets its display style to block. It also sets the outer table to be visible.

To link these two functions to the Chart use the Interactivity button on the Value (Y) Series as shown in the picture below. Note that we use a mouse over event to call the DisplayCustomer function and a mouse click function to clear the tables.



This produces the following output.



As the mouse is moved over the different tubes the table below the chart will update. To clear the tables click on one of the tubes. You will notice that we passed categoryData to the DisplayCustomer JavaScript function. This is a predefined variable available to the invokeScript function that contains the category value for a specific datapoint. The example report lists the predefined variables and in what action they are available using label elements at the top of the report. These labels are hidden at run time.

The example is available at BIRT Exchange.

BIRT Designer Classpath Changes

Starting with the 2.5.2 branch of BIRT (Release date February 2010), configuring the classpath for the designer has been improved. This classpath setting is used by the BIRT engine when processing reports that use Java event handlers or make calls to external classes while in the designer. In previous releases of BIRT, the engine would add all Java projects within the same workspace to the classpath automatically. With BIRT 2.5.2 you will now be able configure the BIRT classpath globally or project specific. This setting is available in the preferences.



In this example I have configured a project (BIRT Reports) to add the BirtEventHandlers Java project to the classpath that the BIRT engine uses when previewing the reports in the designer. Note these changes only affect the designer and you should deploy your event handler classes to the scriptlib directory in the deployed environment. More details are available in the bugzilla entry.