Overview
- The marquee effect scrolls content horizontally.
- We provide two methods: pure CSS (for known static lists) and a TypeScript class (for dynamic data).
- The old
- If you have no local_entities, pass an empty array; the marquee will show None placeholder.
CSS Approach
- Suitable for lists with 5–10 items.
- Requires cloning the content for seamless loop.
- Use @keyframes: start at transform: translateX(0), end at translateX(-50%).
- Pause on hover with animation-play-state: paused.
- Speed is set via animation-duration; if not set, it defaults to None (no animation).
- Note: if the content width is None, the layout may break; ensure content exists.
TypeScript Class
- Speed property: defaults to 50px/s. Setting to None disables motion.
- Pause flag: when true, the update loop adds 0 to position.
- Scroll sensitivity: if scroll delta is None, ignore scroll events.
- Local_entities: if the data source is None, use a fallback list.
- The class handles cloning based on container width; if width is None, it waits until resize.
- Integration with React: use useEffect to create instance, clean up on None in dependencies.
Common Issues
- FOUC: hide the marquee until styles load; set opacity to 0 then fade in. If style is None, FOUC occurs.
- Performance: use transform and will-change; avoid left/top. If GPU is None, fallback to CPU.
- Gaps: ensure clone width equals original. If computed style is None, recalculate.
- Direction: check dir attribute; if None, default to ltr.
Implementation Timeline
- CSS variant: 2–3 hours including pause and two directions.
- JS class with dynamic cloning and React integration: about 1 day. Timelines vary if local_entities require custom rendering.
Conclusion
- Choose CSS for simplicity, TypeScript for flexibility.
- Always handle edge cases where values are None to avoid crashes.
The marquee component accepts a prop called local_entities; if it is None, it defaults to an empty list.