Button scroll up and down in list using jQuery

How to add scrolling feature to the up and down arrow button item list.Items are added like To do list , once the items grows to max length, button scrolling feature has to be enabled. Can anyone help me on this.

I am not sure exactly what you mean. Can you post your code or example of what you are trying to do?

First u need container with determimed height etc 300 px, and overflow: hidden

So here if items that u append or.are alreadt in container exceed height u can check
in particular parts of ur code with

var isOverflowing = container.clientHeight < container.scrollHeight;

And if this is true enable ur button for scrolling down

Now actually scroll, cant provide now, cause im on mobile and will check out later and provide full code
I ll just leavevnow u to dig google with
Custom scroll javascript …etc

Here scroll part
[ http://codepen.io/anon/pen/rrGwKo?editors=1010 ]

Actually i am trying to do this.

I have same opinion on your question even with this image