Apryse Setup

The Velt Apryse WebViewer integration is documented for React. This guide covers the React integration only.

Setup

Step 1: Add Comment components

Add the Velt Comments component to the root of your app.
This component is required to render comments in your app.
Set the text mode prop to false to hide the default text comment tool.

React / Next.js

<VeltProvider apiKey="API_KEY">
  <VeltComments textMode={false} />
</VeltProvider>

Step 2: Install the Velt Apryse package

npm i @veltdev/apryse-velt-comments

@veltdev/apryse-velt-comments lists @pdftron/webviewer as a peer dependency — install it yourself (the package won’t bring its own copy, to avoid running two WebViewer runtimes in the same browser):

npm i @pdftron/webviewer

Serve Apryse’s runtime assets Apryse’s WebViewer isn’t just JavaScript — it ships with a WebAssembly core, the Office Editor engine, and a UI shell (HTML/CSS/JS), all under node_modules/@pdftron/webviewer/public/. These are loaded at runtime over HTTP from a URL on your site (the path option you pass to WebViewer(...)), not via a JS import — so your bundler won’t pick them up on its own. You need to copy them into your app’s static folder so the browser can fetch them. Most teams automate this with a postinstall script:

// scripts/copy-webviewer-assets.mjs
import { cpSync, existsSync, mkdirSync, rmSync } from 'node:fs';
import { dirname, resolve } from 'node:path';
import { fileURLToPath } from 'node:url';

const __dirname = dirname(fileURLToPath(import.meta.url));
const root = resolve(__dirname, '..');
const src = resolve(root, 'node_modules/@pdftron/webviewer/public');
const destDir = resolve(root, 'public/lib/webviewer');

if (!existsSync(src)) {
  console.warn('[copy-webviewer-assets] @pdftron/webviewer not installed yet — skipping.');
  process.exit(0);
}

rmSync(destDir, { recursive: true, force: true });
mkdirSync(destDir, { recursive: true });
for (const folder of ['core', 'ui']) {
  cpSync(resolve(src, folder), resolve(destDir, folder), { recursive: true });
}

Wire it up in package.json:

{
  "scripts": {
    "postinstall": "node scripts/copy-webviewer-assets.mjs"
  }
}

After install, the assets are at public/lib/webviewer/core/ (WASM + PDF/Office engines) and public/lib/webviewer/ui/ (WebViewer UI shell) — which is exactly what the path: 'lib/webviewer' option in WebViewer(...) (see Step 3) points to.

Step 3: Create an Apryse WebViewer component with Velt Comments

Attach the extension to the WebViewer instance once it’s created. The instance is then the handle that every addComment / renderComments call uses.
@pdftron/webviewer touches the DOM, so import it dynamically (only in the browser) to stay SSR-safe in Next.js, Remix, etc.

React / Next.js

import { useEffect, useRef, useState } from 'react';
import { useCommentAnnotations } from '@veltdev/react';
import {
  ApryseVeltComments,
  addComment,
  renderComments,
} from '@veltdev/apryse-velt-comments';

function ApryseEditor() {
  const viewerRef = useRef(null);
  const instanceRef = useRef(null);
  const extensionRef = useRef(null);
  const [instance, setInstance] = useState(null);

  const annotations = useCommentAnnotations();

  useEffect(() => {
    if (!viewerRef.current || instanceRef.current) return;
    let cancelled = false;

    import('@pdftron/webviewer').then(({ default: WebViewer }) => {
      if (cancelled) return;
      WebViewer(
        {
          path: 'lib/webviewer',
          licenseKey: 'YOUR_APRYSE_LICENSE_KEY',
          initialDoc: '/your-document.docx',
          initialMode: 'docxEditor',
        },
        viewerRef.current,
      ).then((webViewerInstance) => {
        if (cancelled) return;
        instanceRef.current = webViewerInstance;

        // Attach the Velt comments extension to the WebViewer instance.
        extensionRef.current = ApryseVeltComments.configure({}).attach(
          webViewerInstance,
        );
        setInstance(webViewerInstance);
      });
    });

    return () => {
      cancelled = true;
      extensionRef.current?.detach();
      extensionRef.current = null;
      instanceRef.current = null;
      setInstance(null);
    };
  }, []);

  useEffect(() => {
    if (instance && annotations) {
      renderComments({ instance, commentAnnotations: annotations });
    }
  }, [instance, annotations]);

  return <div ref={viewerRef} style={{ width: '100%', height: '100vh' }} />;
}

Step 4: Add a comment button to your WebViewer

Add a button that users can click to add comments after selecting text in the document.
Unlike DOM-based editors, Apryse selections live in the WebViewer’s canvas — clicking a button in the host page does not clear the selection, so no onMouseDown / preventDefault dance is needed. Just call addComment({ instance }).

React / Next.js

import { addComment } from '@veltdev/apryse-velt-comments';

function AddCommentButton({ instance }) {
  const handleAddComment = async () => {
    if (!instance) return;
    await addComment({ instance });
  };

  return <button onClick={handleAddComment}>Add Comment</button>;
}

Step 5: Call `addComment` to add a comment

Call this method to add a comment to the currently selected text in the WebViewer. You can use this when the user clicks on the comment button or presses a keyboard shortcut.
Params: AddCommentArgs. It has the following properties:
- instance: The Apryse WebViewerInstance returned by WebViewer(...).
Returns: AddCommentResult or null. Resolves to null if no text is selected or the Velt SDK is not yet loaded. On success it returns:
- veltAnnotationId: The Velt annotation id assigned by the SDK.
- textEditorConfig: The durable logical anchor stored on the annotation ({ editorId, text, pageNumber, occurrence }).

React / Next.js

import { addComment } from '@veltdev/apryse-velt-comments';

const handleAddComment = async () => {
  const result = await addComment({ instance });
  if (!result) {
    console.warn('Add comment failed — make sure text is selected.');
    return;
  }
  console.log('Created annotation:', result.veltAnnotationId);
};

To scope comments to a specific WebViewer (multi-viewer pages), set the editor id when you attach the extension: ApryseVeltComments.configure({ editorId: 'EDITOR_ID' }).attach(webViewerInstance). renderComments will then only paint annotations whose stored editorId matches.

Step 6: Render comments in the WebViewer

Use the useCommentAnnotations hook from @veltdev/react to get comment data from Velt and render it in the WebViewer.
Params: RenderCommentsArgs. It has the following properties:
- instance: The Apryse WebViewerInstance.
- commentAnnotations: Array of Comment Annotation objects from Velt.

React / Next.js

import { useEffect } from 'react';
import { renderComments } from '@veltdev/apryse-velt-comments';
import { useCommentAnnotations } from '@veltdev/react';

const annotations = useCommentAnnotations();

useEffect(() => {
  if (instance && annotations) {
    renderComments({
      instance,
      commentAnnotations: annotations,
    });
  }
}, [instance, annotations]);

The library uses a durable logical anchor (text + occurrence) per comment — anchors survive document edits, page reflow, and viewer ↔ docxEditor mode switches. Physical positions are re-derived at render time.

Step 7: Clean up when the component unmounts

ApryseVeltComments.configure(...).attach(instance) returns an AttachedExtension handle. Call detach() from your effect cleanup so every Apryse listener and per-instance cache is released.
If you switch documents inside the same WebViewer (e.g. via instance.UI.loadDocument(...)), you do not need to detach/re-attach — the extension listens for Apryse’s beforeDocumentLoaded / documentLoaded events and re-syncs the comment highlights automatically.

React / Next.js

useEffect(() => {
  // ...attach as in Step 3...
  extensionRef.current = ApryseVeltComments.configure({}).attach(webViewerInstance);

  return () => {
    // Removes textSelected / pagesUpdated / documentLoaded / docx-edit
    // listeners and clears the per-instance annotation + page-text caches.
    extensionRef.current?.detach();
    extensionRef.current = null;
  };
}, []);

Step 8: Style the commented text

Comment highlights are rendered as positioned <div> elements inside <velt-comment-text> annotation overlays that Apryse manages on each page.
The default styles are set via inline !important rules, so to override them target the inner highlight class with a higher-specificity selector or !important.

/* Override the default yellow highlight */
velt-comment-text .velt-apryse-highlight {
  background-color: rgba(60, 130, 246, 0.30) !important;
  border-bottom: 2px solid rgba(60, 130, 246, 0.95) !important;
}

/* Hover state — apply to the host element */
velt-comment-text:hover .velt-apryse-highlight {
  background-color: rgba(60, 130, 246, 0.50) !important;
}

<velt-comment-text> lives inside the <apryse-webviewer> shadow root, so global CSS automatically reaches it (the browser applies host-page styles into open shadow roots for unknown custom elements).

APIs

ApryseVeltComments.configure()

Creates the Velt Comments extension for the Apryse WebViewer. It exposes a configure(...).attach(instance) pattern — each .attach() returns a handle whose .detach() undoes everything for that instance.

Params: config?: ApryseVeltCommentsConfig
- editorId?: string - Unique identifier for this WebViewer instance (for multi-viewer scenarios). Default: 'apryse'.
Returns: ApryseVeltComments (call .attach(instance) to wire it to a WebViewer, which returns an AttachedExtension)

React / Next.js

import { ApryseVeltComments } from '@veltdev/apryse-velt-comments';

const extension = ApryseVeltComments.configure({
  editorId: 'my-editor',
}).attach(webViewerInstance);

// later, on unmount:
extension.detach();

addComment()

Creates a comment annotation for the currently selected text in the WebViewer.

Params:
- request: AddCommentArgs
  - instance: WebViewerInstance
Returns: Promise<AddCommentResult | null>

React / Next.js

import { addComment } from '@veltdev/apryse-velt-comments';

<button
  onClick={async () => {
    const result = await addComment({ instance });
    if (result) {
      console.log('Created annotation:', result.veltAnnotationId);
    }
  }}
>
  Comment
</button>

renderComments()

Renders and highlights comment annotations in the WebViewer.

Params:
- request: RenderCommentsArgs
  - instance: WebViewerInstance
  - commentAnnotations: CommentAnnotation[]
Returns: void

React / Next.js

import { useEffect } from 'react';
import { renderComments } from '@veltdev/apryse-velt-comments';
import { useCommentAnnotations } from '@veltdev/react';

const annotations = useCommentAnnotations();

useEffect(() => {
  if (instance && annotations) {
    renderComments({
      instance,
      commentAnnotations: annotations,
    });
  }
}, [instance, annotations]);

Get Started

Agentic Setup

Key Concepts

Async Collaboration

Realtime Collaboration

AI

Self-Host Data

Backend SDKs

Model Context Protocol

Webhooks

Security

Miscellaneous

Apryse Setup

Setup

Step 1: Add Comment components

Step 2: Install the Velt Apryse package

Step 3: Create an Apryse WebViewer component with Velt Comments

Step 4: Add a comment button to your WebViewer

Step 5: Call `addComment` to add a comment

Step 6: Render comments in the WebViewer

Step 7: Clean up when the component unmounts

Step 8: Style the commented text

APIs

ApryseVeltComments.configure()

addComment()

renderComments()

​Setup

​Step 1: Add Comment components

​Step 2: Install the Velt Apryse package

​Step 3: Create an Apryse WebViewer component with Velt Comments

​Step 4: Add a comment button to your WebViewer

​Step 5: Call addComment to add a comment

​Step 6: Render comments in the WebViewer

​Step 7: Clean up when the component unmounts

​Step 8: Style the commented text

​APIs

​ApryseVeltComments.configure()

​addComment()

​renderComments()

Setup

Step 1: Add Comment components

Step 2: Install the Velt Apryse package

Step 3: Create an Apryse WebViewer component with Velt Comments

Step 4: Add a comment button to your WebViewer

Step 5: Call `addComment` to add a comment

Step 6: Render comments in the WebViewer

Step 7: Clean up when the component unmounts

Step 8: Style the commented text

APIs

ApryseVeltComments.configure()

addComment()

renderComments()