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Null last series leaves label off of legend





We have come into an issue with jChartFX in displaying multi-series legend labels in a chart.  In this case we are using a line chart.  The problem is when the last series has null data (i.e. no data points), but there is a series label, that series label does not show on the legend.


If there null series in the middle (like series 3 of 5) that label IS shown in the legend. 


The only workaround is to create a datapoint for the last series, then the legend label shows.


Example attached. 

In the example attached there are 5 series.  Series #3 and series #5 are null.  You will see that series' 3 label (i.e. "Category3") is shown in the legend, but series' 5 label is not shown in the legend (i.e. "Category5").


Even though the data has no values, it is important to know that the series was included in the chart; it's just that there was no data.



jChartFX - Issue with null last series.html

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The misunderstanding is that trying to get a specific series (last loop) or setting its text does not create a series so the chart is not aware of the existence of such series.


One way to fix this would be for you to tell us the size of your data set before you pass the values, i.e. before you call chartdata.setItem



This will also result in better performance as we can preallocate the right size of buffers and not have to "grow" them as needed when you pass the data without telling us the size of the data set.
Also this means you do not need the try/catch in the loop that sets the series labels, you needed that because the last series does not exist so when you say getSeries().getItem(4) it was probably failing or returning null
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