How to create a custom field?

Hello,
I'm trying to create a custom field in WordPress to add vine videos.
I found the guide which demonstrate how to add a custom meta box for YouTube videos only.
http://www.iamclarence.com/blog/201…dding-a-youtube-meta-box-to-pagepost-editing/
Can anyone help me to change that metabox from YouTube Videos to Vine.co Videos?
This is the function to OutPut the Vine

PHP:

function vine($id) { // gets the raw .mp4 url from the vine id

    $vine =…

How to create a custom field?

See original post by ibadullah