sneas / img-comparison-slider

Image comparison slider. Compare images before and after. Supports React, Vue, Angular.

img-comparison-slider

Slider Component for Comparing Images (Before and After).

Usage examples: https://img-comparison-slider.sneas.io/examples.html

Most Important Features

• Mobile friendly
• Accessible
• Responsive
• Compact - less than 12 kB minified (Or less than 4 kB if gzipped)
• Compatible with modern frameworks (React, Angular, Vue2, Vue3)
• Distributed via CDN or NPM

Installation

Browser Requirements

• Support for ECMAScript 2015 (ES6). Use Babel if needed.
• Support for Custom Elements (V1) and ShadowDOM (V1). Use Polyfills if support for older browsers is needed.
• Support for CSS Variables (Custom Properties). Polyfill it for IE11.

HTML

<script
  defer
  src="https://cdn.jsdelivr.net/npm/img-comparison-slider@8/dist/index.js"
></script>
<link
  rel="stylesheet"
  href="https://cdn.jsdelivr.net/npm/img-comparison-slider@8/dist/styles.css"
/>

<img-comparison-slider>
  <img slot="first" src="before.jpg" />
  <img slot="second" src="after.jpg" />
</img-comparison-slider>

Frameworks Support

• React
• Angular
• Vue2
• Vue3

Supported Attributes

Besides the default HTMLElement attributes such as class, tabindex, title, etc., img-comparison-slider supports:

Attribute	Description	Default	Available
value	Position of the divider in percents.	50	0..100
hover	Automatically slide on mouse over.	false
direction	Set slider direction.	horizontal	horizontal, vertical
nonce	Define nonce which gets passed to inline style.
keyboard	Enable/disable slider position control with the keyboard.	enabled	enabled, disabled
handle	Enable/disable dragging by handle only.	false	true, false

Events

The component emits slide event when the slider position is changed by user.

Styling

Some styling techniques and ideas can be found in examples.

The component elements like the default handle or the separator line could be styled using CSS3 variables.

Example:

<style type="text/css">
  img-comparison-slider {
    --divider-width: 2px;
    --divider-color: #c0c0c0;
    --default-handle-opacity: 0.3;
  }
</style>

Available Variables

Variable	Description	Default value	Example value
--divider-width	Width of the vertical line separating both images	1px	1em
--divider-color	Color of the vertical line separating the two images	#fff	rgba(0, 0, 0, 0.5)
--divider-shadow	Shadow cast by the vertical line separating the two images	none	0px 0px 5px rgba(0, 0, 0, 0.5)
--handle-position-start	Handle position on the divider axis. In case the handle must be displaced off the center	50%
--default-handle-width	Width of the default handle	50px
--default-handle-color	Color of the default handle	#fff	rgba(0, 0, 0, 0.5)
--default-handle-opacity	Opacity of the default handle	1	0.3
--default-handle-shadow	Shadow cast by the default handle	none	0px 0px 5px rgba(0, 0, 0, 1)

Handle

The handle of the component can be changed by assigning the attribute slot="handle" to any element within img-comparison-slider.