Clean Android WebView Caching
Article Summary
Microsoft Teams Android engineers cut WebView initialization time by 70% using a clever caching technique. Here's how they avoided memory leaks while sharing WebViews across activities.
The Teams Android app hosts multiple third-party web apps, each requiring costly WebView initialization (3.8s P95). Engineer Vishal Ratna shares how the team solved this performance bottleneck without leaking activity contexts.
Key Takeaways
- WebView initialization dropped from 3.8s to 1.2s (70% improvement)
- MutableContextWrapper enables safe WebView pooling with application context
- Pool swaps activity context on obtain() and application context on release()
- Approach prevents memory leaks while maintaining most WebView functionality
- Solution works for apps needing multiple WebView instances across activities
Critical Insight
By creating WebViews with application context wrapped in MutableContextWrapper, Teams achieved 70% faster load times without memory leaks.
