sheva | Parser combinator in Javascript | Parser library

for a Histogram, getSelection() only returns the index of the selected bar,
it does not return the row indexes from the data table,
as it does with other charts.

in this case, we need to use --> getChartLayoutInterface()
the layout interface is an object we can use to find the position of various chart elements.

first, we use getSelection() to determine which bar, and / or series, is selected.
getSelection() will return something similar to --> [{"row":3,"column":1}]

where row is the selected bar, and column is the data table column,
and column - 1 is the series index.

next, we use the layout interface method --> getBoundingBox(id)
where id is the id of the chart element, for a bar it takes the following format.
bar#series#row -- bar#0#3
as such, getBoundingBox('bar#0#3') will give us the dimensions of the fourth bar.
something like --> {"left":381,"top":60.5,"width":89,"height":103}

then we can use layout interface method --> getHAxisValue(position)
this will return the value on the x-axis for the given position

by providing the left and right coordinates of the bar,
we can determine the min and max values of the range

with the range, we can then filter the data table to determine which rows make up the bar.

here is the snippet...