Hi Abhishek,
There is some API documentation available for the sap.ui.vk
library in the SAPUI5 Demo Kit (version 1.32) - see link below:
- SAPUI5 SDK - Demo Kit (note that the link may not be available to you, depending on your permissions)
There will be more documentation available in later releases of SAPUI5 (from version 1.34 onwards), which will include tutorials, SAP Explored examples, and also select information on some of the controls.
I hope this helps.
Regards,
Ana