Flutter Dev

Flutter Development Skill

Overview

This Skill provides modular Flutter development guidance with access to detailed documentation for specific libraries and patterns.

Quick Start: When user mentions a specific library (e.g., "use Bloc", "Riverpod", "GoRouter"), read the corresponding ./rules/*.md file before responding.

Module 1: State Management

Core Principles

• Prefer built-in solutions for simple state (ValueNotifier, ChangeNotifier, StreamBuilder)
• Choose state management based on complexity and team familiarity
• Read detailed rules when using specific libraries

Extended Rules Index

Usage: Read the rule file when user mentions trigger keywords.

Quick Reference

For simple state: Start with ChangeNotifier or ValueNotifier For complex apps: Use Bloc or Riverpod When unsure: Ask user about their preferences and app complexity

Module 2: Testing

Core Principles

• Write tests that can actually fail if real code is broken
• Use Mocktail for mocks (preferred over Mockito)
• Always use group() for test organization

Extended Rules Index

Testing Checklist

Test Quality Checklist:
- [ ] Test can fail if real code is broken
- [ ] Tests are grouped with group()
- [ ] Test names use "should" format
- [ ] Mocks are used appropriately

Module 3: Navigation & Routing

Core Principles

• Use GoRouter for all navigation (declarative approach)
• Prefer named routes over hardcoded paths
• Centralize route definitions

Extended Rules Index

Quick Reference

// Navigation actions
context.goNamed('profile')      // Switch screen
context.pushNamed('details')     // Stack screen
context.pop()                    // Go back

Module 4: Code Quality & Standards

Core Principles

• Follow Effective Dart guidelines
• Use dart analyze and dart format regularly
• Write self-documenting code with clear naming

Extended Rules Index

Naming Standards

Code Quality Checklist

- [ ] Functions < 20 lines
- [ ] Single responsibility per function
- [ ] Descriptive names, no abbreviations
- [ ] Proper error handling with developer.log()
- [ ] Run: dart analyze && dart format .

Module 5: Architecture & Data

Core Principles

• Separate concerns: Presentation, Business Logic, Data layers
• Use repositories to abstract data sources
• Keep business logic out of UI widgets

Extended Rules Index

Architecture Layers

┌─────────────────────────────────┐
│   Presentation Layer (UI)        │
│   - Widgets                      │
│   - Blocs/Cubits/Providers       │
└─────────────────────────────────┘
              ↓
┌─────────────────────────────────┐
│   Business Logic Layer          │
│   - Use cases / Services         │
│   - Business rules               │
└─────────────────────────────────┘
              ↓
┌─────────────────────────────────┐
│   Data Layer                     │
│   - Repositories                 │
│   - Data sources (API, DB)       │
└─────────────────────────────────┘

Common Workflows

Workflow: New Flutter Feature

Feature Development Progress:
- [ ] 1. Define data models (with json_serializable if needed)
- [ ] 2. Create repository/service layer
- [ ] 3. Implement business logic (use appropriate state management)
- [ ] 4. Build UI widgets (break into small components)
- [ ] 5. Write tests (unit → widget → integration)
- [ ] 6. Run: dart analyze && dart format

When user starts a new feature: Reference this workflow and ask which step they're on.

Workflow: Choosing State Management

State Management Decision Tree:
1. Is state simple and local? → ValueNotifier / ChangeNotifier
2. Is state complex/shared? → Bloc / Riverpod / Provider
3. Does user/event tracking matter? → Bloc
4. Is type safety a priority? → Riverpod
5. What does the team prefer? → Ask user

Workflow: Setting Up Navigation

GoRouter Setup Checklist:
- [ ] 1. Add go_router dependency
- [ ] 2. Create app_router.dart with route definitions
- [ ] 3. Use MaterialApp.router in main.dart
- [ ] 4. Define routes with GoRoute (path, name, builder)
- [ ] 5. Implement guards/redirect if needed
- [ ] 6. Test navigation flows

Anti-patterns to Avoid

Troubleshooting Guide

Common Errors

Debugging Commands

# Analyze code
dart analyze

# Format code
dart format .

# Run tests
flutter test

# Check dependencies
flutter pub deps

Quick Command Reference

# Project creation
flutter create my_app

# Dependency management
flutter pub add <package>
flutter pub remove <package>
flutter pub upgrade

# Code quality
dart analyze
dart format .
dart fix --apply

# Testing
flutter test
flutter test --coverage

References

• evanca/flutter-ai-rules - Source of these rules
• Flutter Documentation
• Dart Language Guide