A cross-platform Flutter app that allows users to browse, search, and explore chemical compounds with detailed information, powered by the PubChem API.
- Displays a curated grid of popular compounds
- Shows:
- Common Name
- Molecular Formula
- Molecular Weight
- Hazard Tag (mocked)
- Compound Image (from CID)
- Search any chemical compound by name
- Displays results with real-time PubChem API data
- Handles loading and error states gracefully
- IUPAC Name
- Molecular Formula & Weight
- Molecular Structure Image
- CAS Number (if available)
- Synonyms
- Hazard Statements (mocked or inferred)
- Description (if available)
- Last 5 compounds viewed are cached using local storage
- Displays from cache when offline
- Uses
Cubit(Bloc package) andGetItfor DI - Modular and scalable architecture
| Tech | Purpose |
|---|---|
| Flutter | Cross-platform UI |
| Dio | Networking |
| Bloc | State management |
| GetIt | Dependency injection |
| Hive / SharedPreferences | Local storage (caching) |
| PubChem API | Chemistry data provider |
git clone https://github.com/your-username/moleculist.git cd moleculist flutter pub get flutter run
Aspirin, Acetone, Benzene, Ethanol, Caffeine, Methane, Chloroform, Sulfuric Acid, Urea, Citric Acid
Moleculist is built with a clean, layered architecture that ensures separation of concerns, testability, and scalability.
lib/ ├── common/ │ ├── resources/ → App-wide resources (e.g., themes, constants). │ ├── services/ → Common services (e.g., logging). │ └── utilities/ → Utility functions and helpers. ├── data/ │ ├── local/ → Local data sources (e.g., Hive for caching). │ └── remote/ → Remote data sources & API clients (e.g., Dio). ├── domain/ │ ├── entities/ → Core business objects (plain Dart objects). │ ├── models/ → Data models with serialization logic. │ ├── repositories/ → Abstract contracts for data layers. │ └── services/ → Business logic and use cases. ├── presentation/ │ ├── blocs/ → State management (Blocs/Cubits). │ └── views/ → UI screens and widgets. └── main.dart → App entry point.
We use Flutter Bloc for predictable state management. Each UI feature is backed by a dedicated Cubit:
Cubit Responsibility CompoundCubit Load default compounds and cache them SearchCubit Perform dynamic search and handle results
All external data (network or local) is accessed via repositories. Each repository:
Implements an abstract class (AbstractCompoundRepository)
Separates data-fetching logic from UI & business rules
Communicates with services, which are consumed by Cubits
This makes the app testable and ready for change or scale.
The service layer coordinates multiple repository calls and composes logic. It contains:
Cache fallback logic
Transformation between raw data and models
Business-specific operations (e.g., batch loading, conditional fallback)
✅ Single Responsibility Principle ✅ Dependency Injection via GetIt ✅ Clean Architecture (Separation of Concerns) ✅ Fail-safe Error Handling ✅ Local caching with override support