Collapsible.

Details, on your terms.

In practice

Use open/onOpenChange for controlled state. Trigger and content are automatically associated.

Installation

Install Coal once. Components and TypeScript declarations are included. React 19 and React DOM 19 are peer dependencies.

npm install http://localhost:3100/downloads/chlohal-coal-ui-0.5.0.tgz

This installs the local package. It is not yet published on npm. See installation for stylesheet setup and integration.

Usage

"use client";
import * as React from "react";
import "@chlohal/coal-ui/styles.css";
import { ChevronDown } from "lucide-react";
import { Collapsible, CollapsibleTrigger, CollapsibleContent } from "@chlohal/coal-ui";
export default function Example() {
    return (<Collapsible>
          <CollapsibleTrigger>
            A few more details <ChevronDown size={14}/>
          </CollapsibleTrigger>
          <CollapsibleContent>
            Built with React and Base UI. Styled with Tailwind. Yours to change.
          </CollapsibleContent>
        </Collapsible>);
}

Source

The original Coal implementation. Use the package export to integrate it.

"use client";
import * as React from "react";
import {
  Action,
  cn,
  useValue,
  useRequired,
  type ActionProps,
} from "./internal.js";
const Context = React.createContext<
  { open: boolean; set: (v: boolean) => void; id: string } | undefined
>(undefined);
export type CollapsibleProps = React.ComponentPropsWithRef<"div"> & {
  open?: boolean;
  defaultOpen?: boolean;
  onOpenChange?: (value: boolean) => void;
};
export function Collapsible({
  open,
  defaultOpen = false,
  onOpenChange,
  children,
  ...props
}: CollapsibleProps) {
  const [v, set] = useValue(open, defaultOpen, onOpenChange);
  const id = React.useId();
  return (
    <Context.Provider value={{ open: v, set, id }}>
      <div {...props}>{children}</div>
    </Context.Provider>
  );
}
export function CollapsibleTrigger({ onClick, ...props }: ActionProps) {
  const c = useRequired(Context, "CollapsibleTrigger");
  return (
    <Action
      {...props}
      aria-expanded={c.open}
      aria-controls={c.id}
      onClick={(e) => {
        onClick?.(e);
        if (!e.defaultPrevented) c.set(!c.open);
      }}
    />
  );
}
export function CollapsibleContent({
  className,
  ...props
}: React.ComponentPropsWithRef<"div">) {
  const c = useRequired(Context, "CollapsibleContent");
  return (
    <div
      {...props}
      id={c.id}
      hidden={!c.open}
      className={cn("coal-collapsible-content", className)}
    />
  );
}

Accessibility checklist

• Provide an accessible name for controls, including icon-only buttons.
• Check keyboard navigation, visible focus and disabled states in your application.
• Do not rely on color alone to communicate status.