Overview
The fps_jank_flash_widget is a Flutter performance monitoring tool that visually flashes when the app fails to render frames within a specified timeframe. Designed for developers, it helps identify rendering bottlenecks by highlighting janky or unresponsive UI moments in real time. The widget integrates seamlessly across all major platforms—Android, iOS, Web, macOS, Windows, and Linux—making it useful during development and testing. It’s particularly effective for diagnosing frame drops and optimizing animations or complex layouts.
Use cases
- Real-time performance debugging
- Identifying UI jank during animation
- Testing app responsiveness on different devices
- Optimizing complex widget trees
- Monitoring frame rate consistency
Key features
- Visual flash indicator for dropped frames
- Cross-platform compatibility
- Configurable threshold for jank detection
- Minimal setup with pub add
- Runtime feedback without additional tools
Suitable for
- Flutter developers troubleshooting performance
- Teams focused on smooth UI experiences
- App testers validating frame rate stability
- Educational use for learning about frame rendering
Considerations
- Not recommended for production builds
- May distract during user testing
- Requires manual activation
- Limited to visual feedback only
- Performance overhead in high-frequency scenarios