Hi Saikiran,
Are you going to re-use this everywhere in your code? - Is it a matter you really need a Custom Control or just a matter to apply this into an UI5 Element?
Custom Controls are better for code re-use but in order to define then, you will end up with more code being executed and also transmitted - even thou they seem to be "good practice" inflating execution time and bytes transferred for no good reason hardly translates into good.
Cheers,
Dan.