Add JavaScript to existing button (Ribbon WorkBench 2016)

Hello Everyone,

I'm new to ribbon workbench. 

when a user clicks on +new button then it should call my JavaScript.

I have installed Ribbon Workbench 2016.

I Selected Form ribbon, on new button I added new command, called my Js file and published it. 

I'm still not able to trigger my JavaScript file.

please help me to fix this issue.

Thanks in Advance.