How to Debug Widget Rebuild Issues or Performance Drops in Complex UI Trees?

Flutter rebuilds widgets efficiently, but unnecessary rebuilds degrade performance.

Symptoms:

• Sluggish scrolling
• Janky transitions
• Excessive rebuild logs

What is the Solutions?

1. Use const constructors

Dart:

const MyWidget(title: 'Welcome');

2. Break down large widgets into smaller, reusable widgets
3. Use Flutter DevTools → “Rebuild Stats”
   • Identify which widgets rebuild frequently
   • Use Performance Overlay in emulator
4. Use debugPrintRebuildDirtyWidgets = true;
5. Add this in main() to log all rebuilds.
6. Memoize heavy widgets with AutomaticKeepAliveClientMixin or CacheExtent

Keep build methods pure and free of logic or data fetch calls.