A lightweight, dependency-free scrollbar library written in vanilla javascript.
- Fully customisable via CSS
- Native scrolling behaviour preserved
- Vertical and horizontal scroll support
- Textarea support
- Horizontal scrolling with mousewheel
Note
MiniBar is currently in a pre-release state so is not yet suitable for production so use with care. The API will be in constant flux until v1.0.0 is released so check back for any changes.
Horizontal scrolling with mousewheel and textarea support are experimental and may not work in certain browsers.
MiniBar utilizes the MutationObserver API to automatically detect changes in content so the dimensions can be updated. It will only use the API if your browser supports it. If it doesn't then you must call the update() method when adding / removing / updating the containers content otherwise the scroll bar position and size will be incorrect.
Install
These methods install original MiniBar from Moebius1
bower
bower install minibarjs
npm
npm install minibarjs
Browser
Grab the files from the CDN and include them in your project:
<link href="https://unpkg.com/minibarjs@latest/dist/minibar.min.css" rel="stylesheet" type="text/css">
<script src="https://unpkg.com/minibarjs@latest/dist/minibar.min.js" type="text/javascript"></script>
You can replace latest with the required release number if needed.
Initialisation
You can instantiate MiniBar by passing a reference to your content as the first parameter of the constructor as either a DOM node or a CSS3 selector string:
new MiniBar(document.getElementById('myContent'));
// or
new MiniBar('#myContent');
MiniBar also accepts an object as a second parameter of the constructor for user defined options:
new MiniBar('#myContent', {
barType: "default",
minBarSize: 10,
hideBars: false, /* v0.4.0 and above */
alwaysShowBars: false,
horizontalMouseScroll: false,
scrollX: true,
scrollY: true,
navButtons: false,
scrollAmount: 10,
mutationObserver: {
attributes: false,
childList: true,
subtree: true
},
/* v0.4.0 and above */
onInit: function() {
/* do something on init */
},
/* v0.4.0 and above */
onUpdate: function() {
/* do something on update */
},
/* v0.4.0 and above */
onScroll: function() {
/* do something on init */
},
classes: {
container: "mb-container",
content: "mb-content",
track: "mb-track",
bar: "mb-bar",
visible: "mb-visible",
progress: "mb-progress",
hover: "mb-hover",
scrolling: "mb-scrolling",
textarea: "mb-textarea",
wrapper: "mb-wrapper",
nav: "mb-nav",
btn: "mb-button",
btns: "mb-buttons",
increase: "mb-increase",
decrease: "mb-decrease",
item: "mb-item", /* v0.4.0 and above */
itemVisible: "mb-item-visible", /* v0.4.0 and above */
itemPartial: "mb-item-partial", /* v0.4.0 and above */
itemHidden: "mb-item-hidden" /* v0.4.0 and above */
}
});
You can also define global options with the MiniBarOptions object:
MiniBarOptions = {
barType: "default",
minBarSize: 10,
hideBars: false,
...
};
Options
hideBars (v0.4.0 and above)
Type: Boolean
Default: false
When set to true the scrollbars will be hidden.
minBarSize
Type: Integer
Default: 50
Sets the minimum size of the scrollbars. This can prevent the scollbar becoming to small when you have a ton of content.
alwaysShowBars
Type: Boolean
Default: false
By default the scrollbars aren't visible until hovering over the content. Set this to true to keep the scrollbars visible at all times.
barType
Type: String
Default: default
Set to progress to display the scrollbars as progress bars.
observableItems (v0.4.0 and above)
Type: Mixed
Default: false
Allows MiniBar to observe descendents and determine whether they're fully or partially visible within the scrolling container or completely out of view.
To use you must pass a CSS3 selector string of the scrolling containers descendents that you want to monitor. When monitored, each descendant will have a className added depending on it's visibility:
.mb-item-visible- item boundaries are completely within the scrolling container..mb-item-partial- item is visible, but it's boundaries are not completely within the scrolling container..mb-item-hidden- item is not visible.
NOTE: Your browser must support the IntersectionObserver API for this to work. The only code run in it's callback is the className changes, so latency is kept to a minimum.
horizontalMouseScroll
Type: Boolean
Default: false
Allow horizontal scrolling with the mousewheel.
navButtons
Type: Object
Default: false
Enable scrollbars with navigation buttons.
scrollAmount
Type: Integer
Default: 10
Increase or decrease the amount scrolled when clicking a nav button.
wheelScrollAmount
Type: Integer
Default: 100
Increase or decrease the amount scrolled when rolling mouse wheel.
Public Methods
destroy()
Destroy the current instance. Removes all nodes and event listeners attached to the DOM by MiniBar.
init()
Initialise the instance after destroying.
update()
Recalculate scollbar sizes / positions. This method is called automatically when the content and window are resized or if content is added / removed. You can call this method manually if you add or remove content.
scrollTo(position, axis) (v0.4.0 and above)
/**
* @param {Number|String} position | Position to scroll to
* @param {String} axis | Scroll axis
*/
Scroll the content to the defined position. This can either be an integer to represent the position in pixels to scroll to or "start" / "end" to scroll to the start / end position.
scrollBy(amount, axis, duration, easing)
/**
* @param {Number} amount Number of pixels to scroll
* @param {String} axis Scroll axis
* @param {Number} duration Duration of scroll animation in ms
* @param {Function} easing Easing function
*/
Scroll the content by a certain amount. You can define which axis to scroll with the axis parameter (defaults to "y").
By default this method animates the scrolling. To control the duration of the animation simply set the number of ms with the duration parameter. Setting to 0 will disable animation.
The default easing used is easeOutQuad, but you can pass your own easing function with the easing parameter.
scrollToTop() (v0.5.0 and above)
Scroll the container to the top
scrollToBottom() (v0.5.0 and above)
Scroll the container to the bottom
To Do
- Add touch / mobile support
Implement Mutation Observers to detect DOM changes?Added in v0.3.0
Copyright © 2017 Karl Saunders | MIT license
