Create Modus Wrapper Component

Create Modus Wrapper Component

Scaffold a new Modus wrapper component following established patterns from the codebase.

When to Use

Use this skill when:

• Creating a new wrapper component for a Modus web component
• You need to integrate a Modus component that doesn't have a wrapper yet
• You want to ensure proper event handling and TypeScript types

Pattern Overview

All Modus wrapper components follow this structure:

1. Import the web component from @trimble-oss/moduswebcomponents-react
2. Define TypeScript props interface with JSDoc comments
3. Use useRef for component reference
4. Use useEffect for event listeners with proper cleanup
5. Forward props to the web component with conditional spreading
6. Handle events via event listeners, not React props

Reference Examples

• Simple wrapper: src/components/ModusButton.tsx - No event listeners needed
• With event listeners: src/components/ModusCheckbox.tsx - Shows event handling pattern
• With dropdown: src/components/ModusDropdownMenu.tsx - Shows menu event handling

Implementation Template

import { useEffect, useRef } from "react";
import { ModusWc[ComponentName] } from "@trimble-oss/moduswebcomponents-react";
import type { ReactNode } from "react";

/**
 * Props for the Modus[ComponentName] component.
 */
export interface Modus[ComponentName]Props {
  /** Description of prop */
  propName?: string;
  
  /** A callback function to handle events. */
  onEventName?: (event: CustomEvent<EventDetailType>) => void;
  
  /** A custom CSS class to apply to the component. */
  customClass?: string;
  
  /** The ARIA label for accessibility. */
  "aria-label"?: string;
}

/**
 * Renders a Modus [component name] component.
 *
 * @example
 * // Basic usage
 * <Modus[ComponentName] propName="value" />
 *
 * @example
 * // With event handler
 * <Modus[ComponentName]
 *   propName="value"
 *   => console.log(event.detail)}
 * />
 *
 * @param {Modus[ComponentName]Props} props - The component props.
 * @returns {JSX.Element} The rendered component.
 * @see {@link https://modus.trimble.com/components/[component]} - Modus documentation
 */
export default function Modus[ComponentName]({
  propName,
  onEventName,
  customClass,
  "aria-label": ariaLabel,
}: Modus[ComponentName]Props) {
  const componentRef = useRef<HTMLModusWc[ComponentName]Element>(null);

  // Set up event listeners if needed
  useEffect(() => {
    const component = componentRef.current;
    if (!component) return;

    const handleEventName = (event: Event) => {
      onEventName?.(event as CustomEvent<EventDetailType>);
    };

    if (onEventName) {
      component.addEventListener("eventName", handleEventName);
    }

    return () => {
      if (onEventName) {
        component.removeEventListener("eventName", handleEventName);
      }
    };
  }, [onEventName]);

  return (
    <ModusWc[ComponentName]
      ref={componentRef}
      prop-name={propName}
      custom-class={customClass}
      aria-label={ariaLabel}
    />
  );
}

Key Patterns

1. Conditional Prop Spreading

For optional props that shouldn't be passed when undefined:

// ✅ CORRECT: Conditional spreading
<ModusWcComponent
  {...(color && { color })}
  {...(variant && { variant })}
  size={size} // Required prop, always pass
/>

// ❌ WRONG: Passing undefined
<ModusWcComponent
  color={color} // May be undefined
  variant={variant} // May be undefined
/>

Reference: src/components/ModusButton.tsx:229-230

2. Event Listener Setup

Always use useEffect with cleanup:

useEffect(() => {
  const component = componentRef.current;
  if (!component) return;

  const handleEvent = (event: Event) => {
    onEvent?.(event as CustomEvent<EventDetailType>);
  };

  if (onEvent) {
    component.addEventListener("eventName", handleEvent);
  }

  return () => {
    if (onEvent) {
      component.removeEventListener("eventName", handleEvent);
    }
  };
}, [onEvent]);

Reference: src/components/ModusCheckbox.tsx:91-150

3. TypeScript Types

Use proper types for web component elements:

// ✅ CORRECT: Proper element type
const componentRef = useRef<HTMLModusWcButtonElement>(null);
const componentRef = useRef<HTMLModusWcCheckboxElement>(null);
const componentRef = useRef<HTMLModusWcDropdownMenuElement>(null);

// Pattern: HTMLModusWc[ComponentName]Element

4. Prop Naming

Web components use kebab-case for props:

// React prop: customClass
// Web component prop: custom-class
<ModusWcComponent custom-class={customClass} />

// React prop: modalId
// Web component prop: modal-id
<ModusWcModal modal-id={modalId} />

5. Event Handler Types

Always type event handlers properly:

// ✅ CORRECT: Typed event handler
onEventName?: (event: CustomEvent<{ value: string }>) => void;

// In handler:
const handleEvent = (event: Event) => {
  onEventName?.(event as CustomEvent<{ value: string }>);
};

Common Event Names

Modus components use these common event names:

• inputChange - For input value changes
• inputFocus - For focus events
• inputBlur - For blur events
• buttonClick - For button clicks
• itemSelect - For menu/dropdown item selection
• menuVisibilityChange - For dropdown menu visibility
• expandedChange - For accordion/collapse state

Check the Modus documentation for component-specific events.

Accessibility

Always include:

• aria-label prop for icon-only or non-text components
• Proper ARIA attributes passed to web component
• Keyboard navigation support (usually handled by web component)

Testing Checklist

• Component renders without errors
• Props are forwarded correctly to web component
• Event listeners are set up and cleaned up properly
• TypeScript types are correct
• Accessibility attributes are included
• Conditional props don't pass undefined values

Common Mistakes to Avoid

1. Missing cleanup: Always return cleanup function from useEffect
2. Wrong event names: Check Modus docs for exact event names
3. Passing undefined: Use conditional spreading for optional props
4. Wrong prop names: Web components use kebab-case, React uses camelCase
5. Missing null checks: Always check componentRef.current before use

Next Steps

After creating the wrapper:

1. Export it from src/components/index.ts (if exists)
2. Create a demo page in src/demos/[component]-demo/page.tsx
3. Add to component reference documentation
4. Test all props and events