Cascading prompt does not work in 1.3

Hi Folks,

I went through Design Studio 1.0: Set up a Cascading Filter in an Application. I am performing exact steps from the video still I am not getting filtered value in second dropbox.

Here is my code:

OnStartup:

DROPDOWN_1.setItems(DS_2.getMemberList("_dbXw4CwZEeS6mO4guBZEDA", MemberPresentation.INTERNAL_KEY, MemberDisplay.TEXT, 20));

DROPDOWN_2.setItems(DS_2.getMemberList("_dbYX8CwZEeS6mO4guBZEDA", MemberPresentation.INTERNAL_KEY, MemberDisplay.TEXT, 20));

On Selection:

DS_2.setFilter("_dbXw4CwZEeS6mO4guBZEDA", DROPDOWN_1. getSelectedValue());

DROPDOWN_2.setItems(DS_2.getMemberList("_dbYX8CwZEeS6mO4guBZEDA", MemberPresentation.INTERNAL_KEY, MemberDisplay.TEXT, 20));

These are exact same lines from video with dimensions changed according to my UNX universe.

Please suggest.

Regards,

Tejas