[](https://github.com/KingSora/OverlayScrollbars)
[](https://github.com/sveltejs/svelte)
[](https://www.npmjs.com/package/overlayscrollbars-svelte)
[](https://www.npmjs.com/package/overlayscrollbars-svelte)
[](#)
# OverlayScrollbars for Svelte
This is the official OverlayScrollbars Svelte wrapper.
## Installation
```sh
npm install overlayscrollbars-svelte
```
## Peer Dependencies
OverlayScrollbars for Svelte has the following **peer dependencies**:
- The vanilla JavaScript library: [overlayscrollbars](https://www.npmjs.com/package/overlayscrollbars)
```
npm install overlayscrollbars
```
- The Svelte framework: [svelte](https://www.npmjs.com/package/svelte)
```
npm install svelte
```
## Usage
The first step is to import the CSS file into your app:
```ts
import 'overlayscrollbars/overlayscrollbars.css';
```
> __Note__: If the path `'overlayscrollbars/overlayscrollbars.css'` is not working use `'overlayscrollbars/styles/overlayscrollbars.css'` as the import path for the CSS file.
## Component
The main entry point is the `OverlayScrollbarsComponent` which can be used in your application as a component:
```svelte
example content
```
### Properties
The component accepts all properties of regular elements such as `div` and `span`.
Additionally it has custom optional properties:
- `element`: accepts a `string` which represents the tag of the root element.
- `options`: accepts an `object` which represents the OverlayScrollbars options.
- `events`: accepts an `object` which represents the OverlayScrollbars events.
- `defer`: accepts an `boolean` or `object`. Defers the initialization to a point in time when the browser is idle.
> __Note__: Its **highly recommended** to use the `defer` option whenever possible to defer the initialization to a browser's idle period.
```svelte
{ /* ... */ } }}
defer
/>
```
### Events
Additionally to the `events` property the `OverlayScrollbarsComponent` emits "native" Svelte events. To prevent name collisions with DOM events the events have a `os` prefix.
> __Note__: Events are still supported even though they are are [deprecated](https://svelte.dev/docs/svelte/v5-migration-guide#Event-changes). This was done to ease migration and will be removed in a future release. Please use the `events` option instead.
```svelte
```
All events are typed, but you can use the `EventListenerArgs` type as utility in case its needed:
```ts
import type { EventListenerArgs } from 'overlayscrollbars';
// example listener
const onUpdated = (event) => {
const [instance, onUpdatedArgs] = event.detail as EventListenerArgs['updated'];
}
```
### Ref
The `ref` of the `OverlayScrollbarsComponent` will give you an object with which you can access the OverlayScrollbars `instance` and the root `element` of the component.
The ref object has two properties:
- `osInstance`: a function which returns the OverlayScrollbars instance.
- `getElement`: a function which returns the root element.
## Primitive
In case the `OverlayScrollbarsComponent` is not enough, you can also use the `useOverlayScrollbars` primitive:
```svelte
```
The primitive is for advanced usage and lets you control the whole initialization process. This is useful if you want to integrate it with other plugins.
### Parameters
Parameters are optional and similar to the `OverlayScrollbarsComponent`.
Its an `object` with optional properties:
- `options`: accepts an `object` which represents the OverlayScrollbars options.
- `events`: accepts an `object` which represents the OverlayScrollbars events.
- `defer`: accepts an `boolean` or `object`. Defers the initialization to a point in time when the browser is idle.
> __Note__: You can also pass a `function` as parameter which returns the object in case the object itself is reactive. This also applies to all fields.
### Return
The `useOverlayScrollbars` primitive returns a `tuple` with two values:
- The first value is the `initialization` function, it takes one argument which is the `InitializationTarget`.
- The second value is a function which returns the current OverlayScrollbars instance or `null` if not initialized.
## License
MIT
