Force the colour of a grouping in a stacked bar chart.

Question

Hello, I'm currently stuck with BIRT as you might expect.

As indicated in the title, I'm looking for a way to force BIRT to associate a specific colour to a grouping in a stacked bar chart.

I need this behaviour because I'm generating several charts using the same parameters and data source, but on different filters.

Because the repartition of the groupings is not perfect depending filter, I get different colors associated for the same grouping in two different charts.

eg:

In chart 1, I get [A,B,C] groupings with blue for A, red for B and orange for C. Because in chart 2 I get only [A, C] groupings, I have blue for A, and red for C.

This behaviour breaks the coherence if both charts are in the same page...

Does anyone has an idea on how to fix this?

Thanks,

Vincent

Answer 1

I have a post on the DevShare over at BIRT Exchange that does just this:

http://www.birt-exchange.org/org/devshare/designing-birt-reports/1231-custom-chart-colors-based-on-data-set-values/

The chart scripting uses values in the Data Set to dynamically set the color on the chart. Here is the key bit from the "beforeDrawDataPoint" event on the chart:

var Condition = dph.getBaseDisplayValue();
if(Condition.contains("Critical")) { fill.set(255, 0, 0);} // Set to RED
else if(Condition.contains("High")){ fill.set(255, 255, 0); } // Set to Yellow
...

Good Luck!