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name: flutter-expertise description: Expert knowledge in Flutter, focusing on State Management and Render Tree optimization.

Flutter Expertise

State Management (Riverpod / BLoC)

• Riverpod: Use ConsumerWidget or ref.watch carefully to limit widget rebuilds. Keep providers small and focused.
• BLoC: Use BlocBuilder with buildWhen to prevent unnecessary rebuilds. Maintain distinct states (Loading, Success, Error).

// Riverpod Example
final counterProvider = StateProvider((ref) => 0);

class CounterText extends ConsumerWidget {
  @override
  Widget build(BuildContext context, WidgetRef ref) {
    // Only rebuilds when counterProvider changes
    final count = ref.watch(counterProvider);
    return Text('Count: $count');
  }
}

Render Tree Optimization

• Avoid rebuilding the entire tree. Extract widgets into smaller const StatelessWidgets.
• Use RepaintBoundary to isolate widgets that paint frequently (e.g., animations).
• Minimize the use of heavy widgets like Opacity and ClipRRect when simpler alternatives exist.

%%{init: {"theme": "default", "flowchart": {"useMaxWidth": true}}}%%
flowchart TD
    A[Build Method Triggered] --> B{Is Widget Const?}
    B -- Yes --> C[Skip Rebuild]
    B -- No --> D[Evaluate State Changes]
    D --> E{Use RepaintBoundary?}
    E -- Yes --> F[Paint Isolated Area]
    E -- No --> G[Paint Entire Tree]