How to customize cell to show an arrow that inform if value is up or down respect last value?

Hi Biagio!
Thank you for posting your question.
 
Could you clarify for us, please, what do you mean by “the last value”? If we understand you correctly, do you want to change the content of the cell based on the difference in the previous and the current value?
One way to track the changes in the values is by using getData().
Also, you can find more information about customizing cells in the customizeCell article.
 
More details about your goals will help us to decide whether it’s possible to solve your task.
 
Best regards,
WebDataRocks Team

Yes. I wish to show an arrow up, down near the value if this is major or minor respect the previous value.
How to?
thanks.

Like “20 (icon Arrow Up) or “20 (icon Arrow Down)” respect last value of the same cell.

Hello Biagio,
Thank you for your feedback.
In such a case, customizeCell approach should work the best for you.
It allows manipulating the content of the cells before they are actually drawn.
Please refer to our docs for more information: https://www.webdatarocks.com/doc/customizecell/.
Regards,
WebDataRocks Team