React Chrono

A flexible and modern timeline component for React.

React Chrono is a modern timeline component for React that offers a variety of features and customization options. It allows you to render timelines in horizontal, vertical, and vertical-alternating modes, display images and videos, and much more.

Table of Contents

• ✨ Features
• 💾 Installation
• 🚀 Getting Started
  • Basic Horizontal Mode
  • Vertical Mode
  • Vertical Alternating Mode
• ⚙️ Props
  • Core Props
  • Timeline Item Model
  • Navigation & Interaction
  • Layout & Sizing
  • Media Handling
  • Content & Display
  • Theming & Styling
  • Slideshow
  • Search
  • Miscellaneous
• 🎨 Customization
  • Rendering Custom Content
  • Custom Icons
  • Nested Timelines
  • Custom Class Names
  • Custom Font Sizes
  • Custom Button Alt Text
• 📦 Examples & Demos
  • CodeSandbox Examples
  • Kitchen Sink Demo
  • Storybook
• 🛠️ Build Setup
• 🧪 Tests
• 🤝 Contributing
• 🧱 Built With
• 💖 Support & Meta
• ✨ Contributors

✨ Features

• 🚥 Multiple Modes: Render timelines in Horizontal, Vertical, or Vertical-Alternating layouts.
• 📺 Slideshow: Auto-play the timeline with slideshow functionality.
• 🖼️ Media Support: Easily display images and videos within timeline cards.
• ⌨️ Keyboard Accessible: Navigate the timeline using keyboard controls.
• 🔧 Custom Content: Render custom React components within timeline cards.
• 🌿 Nested Timelines: Display timelines within timeline cards for complex narratives.
• ⚡ Data-Driven API: Configure the timeline dynamically using a simple data structure.
• 🎨 Theming: Customize colors and appearance with ease.
• 🎭 Custom Icons: Use your own icons for timeline points.
• 💪 TypeScript: Built with TypeScript for robust development.
• 💅 Styled with Styled Component: Leverages Styled Component for flexible styling.

💾 Installation

# Using yarn
yarn add react-chrono

# Using npm
npm install react-chrono

🚀 Getting Started

Ensure you wrap the Chrono component in a container with a specified width and height.

Basic Horizontal Mode

By default, if no mode is specified, the component renders in HORIZONTAL mode.

import React from "react";
import { Chrono } from "react-chrono";

const App = () => {
  const items = [
    {
      title: "May 1940",
      cardTitle: "Dunkirk",
      url: "http://www.history.com",
      cardSubtitle: "Men of the British Expeditionary Force (BEF) wade out to a destroyer...",
      cardDetailedText: "Men of the British Expeditionary Force (BEF) wade out to a destroyer during the evacuation from Dunkirk.",
      media: {
        type: "IMAGE",
        source: {
          url: "http://someurl/image.jpg"
        }
      }
    },
    // ... more items
  ];

  return (
    <div style={{ width: "800px", height: "400px" }}>
      <Chrono items={items} />
    </div>
  );
};

export default App;

Vertical Mode

To render the timeline vertically, set the mode prop to VERTICAL.

<div style={{ width: '300px', height: '950px' }}>
  <Chrono items={items} mode="VERTICAL" />
</div>

Vertical Alternating Mode

For a layout where cards alternate sides, use VERTICAL_ALTERNATING.

<div style={{ width: '500px', height: '950px' }}>
  <Chrono items={items} mode="VERTICAL_ALTERNATING" />
</div>

⚙️ Props

React Chrono offers a wide range of props for customization.

Core Props

Name	Type	Default	Description
items	TimelineItemModel[]	[]	An array of Timeline Item objects to display.
mode	'HORIZONTAL', 'VERTICAL', 'VERTICAL_ALTERNATING'	'HORIZONTAL'	Sets the layout mode of the timeline. Changed to HORIZONTAL from VERTICAL_ALTERNATING for new projects.
theme	Theme	{...}	Customizes colors. See Theming & Styling for details.

Timeline Item Model

Each object in the items array can have the following properties:

Property	Type	Description
title	string	Title of the timeline item (often a date or short label).
cardTitle	string	Title displayed on the timeline card.
cardSubtitle	string	Subtitle text displayed on the timeline card.
cardDetailedText	string or string[]	Detailed text for the card. An array of strings will render each string as a separate paragraph.
media	TimelineMediaModel	Object to configure image or video display. See Media Handling.
url	string	URL associated with the timeline item's title. Clicking the title will navigate to this URL.
date	Date or string	Date to be used in the title. If provided, this will override the title property for display purposes.
timelineContent	ReactNode	Custom React content to render inside the card. Overrides cardDetailedText. See Rendering Custom Content.
items	TimelineItemModel[]	Array of timeline items for creating Nested Timelines.
active	boolean	If true, this item will be initially active (only for the first matching item).
id	string	A unique identifier for the timeline item.
visible	boolean	Controls the visibility of the timeline item.

Example TimelineItemModel:

{
  title: "May 1940",
  cardTitle: "Dunkirk",
  cardSubtitle: "Evacuation of Allied soldiers from the beaches and harbour of Dunkirk, France.",
  cardDetailedText: ["Paragraph one about Dunkirk.", "Paragraph two providing more details."],
  media: {
    type: "IMAGE", // "VIDEO"
    source: {
      url: "http://someurl/dunkirk.jpg"
    },
    name: "Dunkirk Evacuation"
  },
  url: "https://en.wikipedia.org/wiki/Dunkirk_evacuation",
  // For nested timeline:
  // items: [{ cardTitle: 'Sub-event 1' }, { cardTitle: 'Sub-event 2' }]
}

Navigation & Interaction

Name	Type	Default	Description
activeItemIndex	number	0	Index of the timeline item to be active on load.
disableNavOnKey	boolean	false	Disables keyboard navigation (LEFT/RIGHT for Horizontal, UP/DOWN for Vertical).
disableClickOnCircle	boolean	false	Disables click action on timeline points/circles.
disableAutoScrollOnClick	boolean	false	Prevents auto-scrolling to the active card when a timeline card or point is clicked.
onItemSelected	function		Callback function invoked when a timeline item is selected. Passes item data and index.
onScrollEnd	function		Callback function invoked when the end of the timeline is reached during scrolling.
focusActiveItemOnLoad	boolean	true	Automatically scrolls to and focuses on the activeItemIndex when the timeline loads.
disableInteraction	boolean	false	Disables all user interactions with the timeline (clicks, keyboard navigation).
enableQuickJump	boolean	true	Allows quick jumping to a timeline item via controls (if toolbar is enabled).
useReadMore	boolean	true	Enables a "read more" button if card content exceeds available space. Set to false to always show all text.

Keyboard Navigation:

• Horizontal Mode: Use LEFT and RIGHT arrow keys.
• Vertical/Vertical Alternating Mode: Use UP and DOWN arrow keys.
• HOME: Jump to the first item.
• END: Jump to the last item.

Layout & Sizing

Name	Type	Default	Description
cardHeight	number	200	Minimum height (in pixels) of timeline cards.
cardWidth	number	450	Maximum width (in pixels) of timeline cards.
itemWidth	number	300	Width (in pixels) of each timeline section in HORIZONTAL mode.
contentDetailsHeight	number	150	Height (in pixels) of the detailed content area within a card if cardDetailedText is used.
lineWidth	number	3	Width (in pixels) of the main timeline track line.
timelinePointDimension	number	16	Diameter (in pixels) of the circular points on the timeline.
nestedCardHeight	number	150	Height (in pixels) of cards within a nested timeline.
scrollable	boolean or { scrollbar: boolean }	true	Makes VERTICAL and VERTICAL_ALTERNATING modes scrollable. Set to { scrollbar: true } to show the scrollbar.
enableBreakPoint	boolean	true	If true, VERTICAL_ALTERNATING mode automatically switches to VERTICAL mode when responsiveBreakPoint is reached.
responsiveBreakPoint	number	768	Viewport width (in pixels) at which VERTICAL_ALTERNATING mode switches to VERTICAL if enableBreakPoint is true. Default changed to 768.
cardPositionHorizontal	'TOP' or 'BOTTOM'	'BOTTOM'	Positions the card above or below the timeline in HORIZONTAL mode. Default changed to 'BOTTOM'.
flipLayout	boolean	false	Reverses the layout direction (e.g., Right-to-Left for horizontal, or swaps sides for vertical alternating).
showAllCardsHorizontal	boolean	false	In HORIZONTAL mode, displays all cards simultaneously instead of only the active one.

Media Handling

The media object within a Timeline Item configures images or videos.

media Property	Type	Description
type	'IMAGE' or 'VIDEO'	Specifies the type of media.
source	{ url: string, type?: string }	url: URL of the image or video. type (for video): e.g., 'mp4', 'webm'.
name	string	Alt text for images or a descriptive name for videos.
active	boolean	(Video only) If true, video will attempt to play when its card becomes active.
id	string	A unique ID for the media element.
videoOptions	HTMLVideoElement attributes	(Video only) An object containing standard HTML5 video attributes like loop, muted, autoPlay, etc.

Image Example:

media: {
  type: "IMAGE",
  name: "dunkirk beach",
  source: {
    url: "http://someurl/image.jpg"
  }
}

Video Example (auto-plays when active, muted):

media: {
  type: "VIDEO",
  name: "Pearl Harbor",
  source: {
    url: "/pearl-harbor.mp4", // or "https://www.youtube.com/embed/f6cz9gtMTeI"
    type: "mp4" // Optional for local files if extension is clear, useful for YouTube embeds
  },
  videoOptions: { autoPlay: true, muted: true }
}

Media Settings Prop (mediaSettings): This top-level prop on <Chrono> controls global media display:

Name	Type	Default	Description
align	'left', 'right', 'center'	'left'	Alignment of media within the card. Default changed to 'left'.
fit	'cover', 'contain', 'fill', 'none', 'scale-down'	'cover'	CSS object-fit property for images.

<Chrono items={items} mediaSettings={{ align: 'right', fit: 'contain' }} />

Content & Display

Name	Type	Default	Description
borderLessCards	boolean	false	Removes borders and shadows from timeline cards for a flatter look.
cardLess	boolean	false	Hides timeline cards, showing only titles/points. Useful for a very compact timeline.
disableTimelinePoint	boolean	false	Hides the circular points on the timeline track.
timelinePointShape	'circle', 'square', 'diamond'	'circle'	Configures the shape of the points on the timeline.
textOverlay	boolean	false	Displays text content as an overlay on top of media elements. Requires text property in timeline items.
parseDetailsAsHTML	boolean	false	If true, cardDetailedText will be parsed as HTML. Use with caution due to XSS risks if content is user-supplied.
titleDateFormat	string	'MMM DD, YYYY'	Date format for item titles when using the date property in items. Supports all day.js formats.
textDensity	'LOW' or 'HIGH'	'HIGH'	Configures the amount of text displayed in cards. 'LOW' might truncate more aggressively.

Text Overlay Mode: Enable textOverlay and provide a text property in your items.

const items = [
  {
    title: 'First item',
    media: { type: 'IMAGE', source: { url: 'https://example.com/image.jpg' }},
    text: 'This is the caption for the first item, appearing over the image.'
  }
];
<Chrono items={items} textOverlay />;

Theming & Styling

Use the theme prop to customize colors:

<Chrono
  items={items}
  theme={{
    primary: 'red',          // Main timeline color (points, lines)
    secondary: 'blue',       // Background color for timeline cards or other elements depending on mode
    cardBgColor: 'yellow',   // Background color of the timeline cards
    cardForeColor: 'black',  // Text color within timeline cards
    titleColor: 'black',     // Color of the timeline item titles (e.g., dates)
    titleColorActive: 'red', // Color of the active timeline item title
  }}
/>

For a complete list of themeable properties, please refer to the Theme type definition in the source code or Storybook examples.

Dark Mode Toggle:

Name	Type	Default	Description
enableDarkToggle	boolean	false	Adds a toggle switch to the toolbar for enabling dark mode (if dark theme is configured).
onThemeChange	function		Callback invoked when the theme changes, e.g., via the dark mode toggle. Passes the new theme object.

Slideshow

Name	Type	Default	Description
slideShow	boolean	false	Enables slideshow mode and shows play/pause controls in the toolbar.
slideItemDuration	number	2000	Duration (in milliseconds) each timeline item remains active during a slideshow. Default changed to 2000.
slideShowType	'reveal', 'slide_from_sides', 'slide_in'	Varies by mode	Type of animation for slideshow transitions. Defaults: VERTICAL -> 'reveal', VERTICAL_ALTERNATING -> 'slide_from_sides', HORIZONTAL -> 'slide_in'.

<Chrono items={items} slideShow slideItemDuration={3000} />

Slideshow can be stopped by clicking the stop button or pressing ESC.

Search

Name	Type	Default	Description
searchPlaceholder	string	"Search..."	Placeholder text for the search input in the toolbar.
searchAriaLabel	string	"Search timeline"	ARIA label for the search input for accessibility.
clearSearch	string	"Clear search"	Text/ARIA label for the clear search button.

<Chrono
  items={data}
  searchPlaceholder="Find in timeline..."
/>

Search functionality is part of the toolbar. To hide search (and the toolbar), set disableToolbar={true}.

Miscellaneous

Name	Type	Default	Description
allowDynamicUpdate	boolean	false	Enables dynamic updates of timeline items. If true, changes to the items prop will re-render the timeline.
noUniqueId	boolean	false	Prevents generating a unique ID for the timeline wrapper. Use with uniqueId if you need to set a specific ID.
uniqueId	string		Sets a custom unique ID for the timeline wrapper. Useful with noUniqueId={true}.
disableToolbar	boolean	false	Hides the entire toolbar/control panel.
toolbarPosition	'TOP' or 'BOTTOM'	'TOP'	Positions the toolbar at the top or bottom of the timeline.
highlightCardsOnHover	boolean	false	Highlights timeline cards on mouse hover.

🎨 Customization

Rendering Custom Content

Pass React elements as children to <Chrono>. Each child will be rendered into a timeline card. This can be combined with the items prop to provide titles or other metadata.

const customItems = [
  { title: '2023-01-01', cardTitle: 'Event One' },
  { title: '2023-02-15', cardTitle: 'Event Two' },
];

<Chrono mode="VERTICAL" items={customItems}>
  <div>
    <h4>Custom Content for Event One</h4>
    <p>This is fully custom JSX rendered in the first card.</p>
  </div>
  <div>
    <img src="<url_to_image>" alt="Custom Image" style={{width: "100%"}} />
    <p>An image in the second card.</p>
  </div>
</Chrono>

Custom Icons

Provide images for timeline points by wrapping them in a div with className="chrono-icons" as a child of <Chrono>. Icons are applied sequentially.

<Chrono items={items} mode="VERTICAL_ALTERNATING">
  {/* Custom content for cards (optional) */}
  <div>Card 1 Content</div>
  <div>Card 2 Content</div>

  {/* Custom icons for timeline points */}
  <div className="chrono-icons">
    <img src="image1.svg" alt="icon1" />
    <img src="image2.svg" alt="icon2" />
    {/* Add more images for more items */}
  </div>
</Chrono>

Nested Timelines

Create timelines within timeline cards by providing an items array within a parent timeline item.

const itemsWithNested = [
  {
    title: 'Main Event 1',
    cardTitle: 'Chapter 1',
    items: [ // Nested timeline
      { cardTitle: 'Sub-event 1.1', cardSubtitle: 'Details for 1.1' },
      { cardTitle: 'Sub-event 1.2', media: { type: "IMAGE", source: { url: '...' } } },
    ],
  },
  { title: 'Main Event 2', cardTitle: 'Chapter 2' },
];

<Chrono mode="VERTICAL" items={itemsWithNested} nestedCardHeight={120} />

Custom Class Names

Apply your own CSS classes to various parts of the timeline using the classNames prop.

<Chrono
  items={items}
  classNames={{
    card: 'my-custom-card',
    cardMedia: 'my-card-media',
    cardSubTitle: 'my-card-subtitle',
    cardText: 'my-card-text',
    cardTitle: 'my-card-title',
    controls: 'my-timeline-controls', // Class for the toolbar
    title: 'my-timeline-title',      // Class for the item titles (e.g., dates)
    timelinePoint: 'my-timeline-point',
    timelineTrack: 'my-timeline-track',
  }}
/>

Custom Font Sizes

Adjust font sizes for card elements using the fontSizes prop.

<Chrono
  items={data}
  fontSizes={{
    cardSubtitle: '0.85rem',
    cardText: '0.8rem',
    cardTitle: '1.1rem',
    title: '0.9rem', // Font size for the main timeline titles (dates)
  }}
/>

Custom Button Alt Text

Customize the alt text for toolbar navigation buttons via buttonTexts.

<Chrono
  items={data}
  buttonTexts={{
    first: 'Jump to First Item',
    last: 'Jump to Last Item',
    next: 'View Next Item',
    previous: 'View Previous Item',
    play: 'Start Slideshow',
    stop: 'Stop Slideshow', // Added for completeness
    jumpTo: 'Jump to specific item' // Added for completeness
  }}
/>

Default buttonTexts values:

Property	Value
first	'Go to First'
last	'Go to Last'
next	'Next'
previous	'Previous'
play	'Play Slideshow'
stop	'Stop Slideshow'
jumpTo	'Jump to'

📦 Examples & Demos

CodeSandbox Examples

Explore various configurations of React Chrono:

• Horizontal Basic
• Horizontal - Show all cards
• Vertical Basic
• Vertical Alternating
• Vertical with All Images
• Vertical with Custom Content
• Vertical Custom Content with items prop
• Custom Icons Example

Kitchen Sink Demo

See a comprehensive demo showcasing many features:

• React Chrono Kitchen Sink

Storybook

Dive into a wide variety of examples hosted on Storybook:

• Horizontal Collection
• Vertical Collection

🛠️ Build Setup

# Install dependencies
pnpm install

# Start development server
pnpm dev

# Lint CSS
pnpm lint:css

# ESLint
pnpm eslint

# Prettier
pnpm lint

# Build library
pnpm rollup

🧪 Tests

# Run unit tests
pnpm test

# Run Cypress tests (interactive)
pnpm cypress:test # or pnpm cypress open

# Run Cypress tests in headless mode
pnpm cypress:headless

# Run Cypress tests in quiet mode (headless, less output)
pnpm cypress:quiet

🤝 Contributing

Contributions are welcome! Please follow these steps:

1. Fork the repository.
2. Create your feature branch (git checkout -b new-feature).
3. Commit your changes (git commit -am 'Add: New amazing feature').
4. Push to the branch (git push origin new-feature).
5. Create a new Pull Request.

Please read CONTRIBUTING.md for more details on the process and CODE_OF_CONDUCT.md.

🧱 Built With

• TypeScript
• Styled with Emotion

💖 Support & Meta

Special thanks to BrowserStack for providing an Open Source License for testing.

Distributed under the MIT license. See LICENSE for more information.

Prabhu Murthy – @prabhumurthy2 – [email protected] GitHub: https://github.com/prabhuignoto

✨ Contributors

Thanks to these wonderful people (emoji key):

Alois 📖	Koji 📖	Alexandre Girard 💻	Ryuya 📖	Taqi Abbas 💻	megasoft78 💻	Eric（书生） 💻
Christophe Bernard 💻

This project follows the all-contributors specification. Contributions of any kind are welcome!