Nuxt Lenis

This is a Nuxt wrapper for Lenis (by Studio Freight) – providing smooth scrolling with support for multiple instances in a type-safe and reactive way.

Version 2 Notice:
In version 2, the module has been refactored to centrally manage multiple Lenis instances via a Nuxt plugin. Use the provided composable (useLenis) for accessing instance methods and reactive scroll state. The component expects an onScroll prop for scroll callbacks (instead of using emits).

---

Getting Started

1. Install the package:

   yarn add nuxt-lenis

2. Add the module in your nuxt.config:

   export default {
      modules: [
         'nuxt-lenis'
      ]
   }

3. Wrap your page with the Lenis component in app.vue:

   <template>
      <lenis
         :options="LenisOptions"
         onScroll="handleScroll"
      >
         <NuxtPage />
      </lenis>
   </template>
   
   <script setup lang="ts">
   const handleScroll = (scrollData: any) => {
      console.log("Scroll event:", scrollData);
   }
   </script>

---

Component Usage

The <lenis> component (located at src/runtime/components/Lenis.vue) accepts the following props:

• id (String, default: "default"): A unique identifier for your Lenis instance.
• root (Boolean, default: true): Determines if the window should be used as the scroll container.
• options (Object): Lenis options (e.g., duration, autoRaf, direction).
• onScroll (Function): Callback fired whenever a scrolling event is received.

Example:

<template>
   <lenis id="default" :options="LenisOptions" onScroll="handleScroll">
      <NuxtPage />
   </lenis>
</template>

<script setup lang="ts">
const LenisOptions = {
   smooth: true,
   duration: 1.2,
   autoRaf: true,
   direction: 'vertical'
}

const handleScroll = (data: any) => {
   console.log("Scroll detected:", data);
}
</script>

---

Composable Usage

Access the reactive Lenis API via the composable. By default, useLenis() returns the following properties:

• createLenis: Function to create and register a Lenis instance.
• getLenis: Function that returns the Lenis instance (or null if not found).
• destroyLenis: Function to destroy an instance.
• scrollState: Function to access the reactive scroll state of an instance.
• watchScrollState: Function to watch changes to the scroll state.

Single Instance Usage

For many cases, a single instance is sufficient:

<script setup lang="ts">
import { watch } from 'vue';
import { useLenis } from '#imports';

const { scrollState, getLenis } = useLenis();

// Example: retrieve default instance
const instance = getLenis(); // returns the Lenis instance or null

// Watch scroll state changes
watch(scrollState, (state) => {
   console.log("Scroll state:", state);
}, { deep: true });
</script>

Multiple Instances

If you need multiple instances, pass false (or use different IDs on each <lenis> component) and access them by ID:

<template>
   <lenis id="main">
      <NuxtPage />
   </lenis>
   <lenis id="modal">
      <NuxtPage />
   </lenis>
</template>

<script setup lang="ts">
import { useLenis } from '#imports';

// Using multiple instance mode:
const { scrollState, getLenis } = useLenis(false);

// Access the instances by ID
const mainInstance = getLenis("main");
const modalInstance = getLenis("modal");

// Example: Log scroll states for each instance
console.log("Main scroll state:", scrollState("main"));
console.log("Modal scroll state:", scrollState("modal"));
</script>

---

Plugin API

The Nuxt plugin (located at src/runtime/plugin.ts) exposes the following methods:

• createLenis(id, options?)
  Creates a new Lenis instance for a given ID and registers it.

• getLenis(id?)
  Retrieves a Lenis instance by its ID (or the default instance if none is specified).

• destroyLenis(id)
  Destroys the specified Lenis instance and cleans up its associated state.

• getScrollState(id?)
  Returns the current scroll state for the specified instance, which is updated reactively.

The composable (useLenis) wraps these methods and provides a streamlined API for your components.

---

Happy scrolling!