Can I set a "More" "Less..." button in my Qlikview extension just like the button in the Qlikview native objects?

[#1]

I found a "solution" in google but it isn't working...

I know that the line nedds to be similar to:

<button class="prop-grid_button prop-grid_span-4 prop-more-less-button" avq="????????" name="barchart">More...</button>

Thanks in advance

Alex