scrollbar-compensate

npm i scrollbar-compensate

A hack to compensate for scrollbar size for modals

Problem

Usually, you would set overflow: hidden to body when the modal mounts. However, this causes a weird adjustment to the layout (because the scrollbar disappears). This mostly affects Windows/Linux users, and some OSX users that use a mouse (because it forces the scrollbar to appear).

As an example, compare Semantic UI's Modal and TWBS' Modal. TWBS solved this by adding a padding-right to the body when the modal mounts.

What It Does

It adds an inline-style that adds a padding-right to the provided selectors. It appends the following to head:

<style>.my-selector, .my-selector-2 .my-nested-selector { padding-right: 15px; }</style>

Take note that the 15px value here may vary depending on your scrollbar width. Typically, OS X has this set to 15px.

Usage

compensate(selectors) — This module only exposes a single function that accepts an array of elements as an argument. Usually, you pass class names here that are added to the body when a modal mounts.

var compensate = require('scrollbar-compensate');

document.addEventListener('DOMContentLoaded', function() {
  compensate(['.modal-open', '.overlay-enabled .global-nav']);
});

Note — If you're wondering why it's necessary to run compensate when the document loads: We're using the scrollbar-size library internally which needs to be called after the document is ready.

Examples

jquery-modal is using this library.

Alternatives

no-scroll also solves this problem, however covers more than scrollbar compensation.

Use this library only if you want the scrollbar compensation library. Otherwise, check the alternatives.

Note

This library isn't available in UMD because I don't really need it at the moment. Please send a PR or submit an issue if you'd like it to be implemented. Moreover, no tests yet.