nav[aria-label="Primary Navigation"] { padding: 0; & ul { list-style: none; width: 100%; display: flex; flex-direction: row; justify-content: start; align-items: start; gap: 30px; padding: 0; & li { margin: 0; } & ul li { list-style: none; } } }

How do you access dataset from a chart element through script

newbie321

Hello, 
I have a chart element in .rptdesign file. it uses the dataset that has two columns (x,y) and are used to make the plot. 
Now depending on how many points are the dataset, I would need to dynamically adjust the properties of the chart, through the beforeGeneration() event handler or any other applicable event handler.
Question: how do I access dataset list values from within the beforeGeneration() event handler as shown below:
function beforeGeneration( chart, icsc ) 
{ 
importPackage( Packages.org.eclipse.birt.chart.model.data.impl ); 
totalPoints = ????? 
}
 
Thanks!!

Find more posts tagged with

Comments

pricher

Hi,
 
You cannot access the dataset when scripting a chart. If you need access to data to change the properties of a chart, you can store the data in a persistent global variable using
 
reportContext.setPersistentGlobalVariable("MyVar", "My Value");
 
and retrieve that content using
 
icsc.getExternalContext().getScriptable().getPersistentGlobalVariable("MyVar");
 
in the beforeGeneration method of the chart.
 
Now, since the modifications you want to make to the chart are based on the number of data points, another solution could be to use something like this:
 
function beforeGeneration( chart, icsc ) 
{ 
xAxis = chart.getBaseAxes()[0]; 
yAxis = chart.getOrthogonalAxes( xAxis, true )[0]; 
seriesDef = yAxis.getSeriesDefinitions().get(0); 
runSeries = seriesDef.getRunTimeSeries()[0]; 
list = runSeries.getDataSet().getValues(); 
if( list.length > 3){ 
chart.getBlock().getBounds().setHeight(150); 
chart.getBlock().getBounds().setWidth(600); 
}else{ 
chart.getBlock().getBounds().setHeight(400); 
chart.getBlock().getBounds().setWidth(600); 
} 
}
 
Hope this helps,
 
P.

newbie321

Thanks for a pointer #pritcher. 
 
After couple days of beating my head against the problem, I actually figured it out this noon. The solution turned out to be simpler than I thought but took forever to produce the workable result.
 
Here is the recipe for the benefit of community:
In the 
<pre class="_prettyXprint">
.beforeGeneration()</pre>
do the following:
<div>
<pre class="_prettyXprint">
data = chart.getAxes().get(0).getAssociatedAxes().get(0).getRuntimeSeries()[0].getDataSet().getValues();</pre>
The data will be of an Array type. So all you have to do is to cycle through the an array using the classic approach:
<pre class="_prettyXprint">
for (i=0; i<data.length;i++){
System.out.println(data[i]);
}</pre>
At this point of time the data corresponding to y-axis is exposed. 
 
Your reply also answered my another question which I wanted to ask but have not had a chance to post. 
Thanks again for the reply.
 
</div>