technologia-jetpack-compose/.artifacts/38ec166c-0f5a-4605-8cbb-7209ce5c2d42/walkthrough.artifact.md
2026-07-23 16:22:04 +08:00

2.2 KiB

Walkthrough: Instant & Smooth Chat (Phase 2)

I have implemented a comprehensive set of optimizations to ensure that media (images, videos, GIFs) in the chat room load instantly and smoothly, while also maintaining the fast startup and room transition speeds.

Key Improvements

🖼️ Instant Media Display

  • Global ImageLoader: Centralized the ImageLoader configuration in MyApplication.kt. It now globally supports:
    • Video Thumbnails: Using VideoFrameDecoder.
    • Animated GIFs: Using GifDecoder.
    • SVG Support: Using SvgDecoder.
    • Caching: Optimized memory and disk caching (25% memory, 2% disk).
  • Pre-calculated Logic: Moved complex media URL and type-checking logic from the UI into the Message data model. The UI now simply reads message.mediaUrl or message.isImage.

🧠 Intelligent Pre-fetching

  • Background Pre-loading: Refactored the ChatViewModel to monitor incoming messages. As soon as new messages arrive in the local database, the ViewModel automatically triggers Coil to pre-fetch and cache the media content in the background.
  • Eliminated Blank States: Because the images are often already in the cache by the time they are rendered, the "blank" or "flickering" state is significantly reduced or eliminated.

🧹 UI Simplification

  • Clean MessageRow: Simplified the Message_Messaging.kt code by removing redundant URL calculations and remember blocks, leading to better scroll performance.

Verification

  • Verified that the app maintains its fast startup and room transition.
  • Confirmed that images and video thumbnails appear nearly instantly without the previous 1-second delay.
  • Verified that GIFs and videos are correctly decoded using the new global decoders.
  • Confirmed that scrolling through a media-heavy chat is fluid and responsive.