Scroll and read slickgrid table into memory - ruby

Question

I have a slickgrid table that I am trying to read into memory using watir-webdriver. Because the full data often cannot be seen without scrolling down, I want to make a function that can scroll through the table and also be able to tally a count of all the rows as well as access any row that might or might not be hidden within it. Here's what I have so far:
class SlickGridTable
def initialize(element)
#element = element
end
...
def scroll_down
location_y = 23
while true
location_y += 1
$browser.execute_script("arguments[0].scrollBy(0, #{location_y});", #element)
end
end
end
However I am regularly getting this error:
Selenium::WebDriver::Error::UnknownError: unknown error: undefined is not a function

Answer 1

I am also working with slickgrid, and considered a similar approach. Instead, I extended the Watir::Div class with a scroll_until_present method. Now we can scroll until present and then work with the data in the grid. I have not had the need to collect all the data after implementing this. Does not solve your problem with tallying rows, but does help find the records you are expecting to see.
# Extends the Watir::Div class to support slick grids
module Watir
class Div
# scrolls until it finds the item you are looking for
# can be used like wait_until_present
def scroll_until_present
scroll_height = browser.execute_script('return document.getElementsByClassName("slick-viewport")[0].scrollHeight')
(0..scroll_height).step(20).each { |item|
browser.execute_script('document.getElementsByClassName("slick-viewport")[0].scrollTop = ' + item.to_s)
if present?
# scroll a little more once the record is found
item += 30
browser.execute_script('document.getElementsByClassName("slick-viewport")[0].scrollTop = ' + item.to_s)
break
end
}
end
end
end