You can see an example here WaterfallChart/waterfall.js at master · mindspank/WaterfallChart · GitHub that produces this properties page
The official documentation for the properties definition is available here https://help.qlik.com/sense/2.0/en-us/developer/Subsystems/Extensions/Content/Overview/visualization-properties.htm
I hope that helps you get started.
Thanks for the reply.
But what i need is something different. In the below extension property there is a create button which is used to add category. And when we expand that there is a delete button to delete that category. I want some thing like this. I found this code from Qlikbranch CSS Menu extension.
I couldn't understand the code completely. They have used a type as array and one more property addTranslation: "Common.Create".
Anyone have idea on how this is created and how to use this property or any documentation for these.
Thanks for the help.