Multi Select with drop down box?

Hello

Is it possible to create a multi select with the drop down box in BEX Web Application Designer? (BI AddOn 7.X – based on 7.3).

I have found the ABAP Standard Class CL_RSR_WWW_ITEM_FILTER_DDOWN which could maybe solve the problem.

Has anyone experience with that issue or any other ideas how I can do this? For example select multiple values using CTRL button?

Regards

Janine