Select2 4.0.0 Bootstrap theme

@fk is working on a Bootstrap 3 theme for Select2 4.0.0.

https://github.com/select2/select2-bootstrap-theme

There is not currently any documentation on creating themes for Select2 4.0.0, but it may help to look at the default theme's SCSS for the selectors.

If you want to use bootstrap styling from Kevin Brown' answer

https://github.com/select2/select2-bootstrap-theme

You add this css file to your page, keep the default select2 styles

<link href="/select2-bootstrap-theme/select2-bootstrap.min.css" type="text/css" rel="stylesheet" />

Then set the theme

$("#elem").select2({theme:"bootstrap"});

Also, use classes .select2-bootstrap-prepend and .select2-bootstrap-append on the .input-group wrapper elements to group buttons and selects seamlessly.