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name: Idiomatic Flutter description: Modern layout and widget composition standards. metadata: labels: [flutter, clean-code, widgets] triggers: files: ['lib/presentation/**/*.dart'] keywords: [context.mounted, SizedBox, Gap, composition, shrink]

Idiomatic Flutter

Priority: P1 (OPERATIONAL)

Modern Flutter layout patterns and composition techniques.

• Async Gaps: Check if (context.mounted) before using BuildContext after await.
• Composition: Extract complex UI into small widgets. Avoid deep nesting or large helper methods.
• Layout:
  • Spacing: Use Gap(n) or SizedBox over Padding for simple gaps.
  • Empty UI: Use const SizedBox.shrink().
  • Intrinsic: Avoid IntrinsicWidth/Height; use Stack + FractionallySizedBox for overlays.
• Optimization: Use ColoredBox/Padding/DecoratedBox instead of Container when possible.
• Themes: Use extensions for Theme.of(context) access.

🚫 Anti-Patterns

• Missing Mounted Check: **No context usage after await**: Always check if (context.mounted).
• Helper Methods for UI: **No Widget functions**: Use specialized Widget classes for better performance/profiling.
• Direct Controller Access: **No UI-Logic coupling**: Use BLoC/Signals to decouple UI from State.