Taskify

A production-ready task management application built with Flutter. Supports full offline CRUD operations backed by Hive local storage, with a clean layered architecture and Provider-based state management.

Setup

1. Ensure Flutter SDK (>=3.10.4) is installed and on your PATH.
2. Clone the repository and navigate into the project root.
3. Run flutter pub get to install dependencies.
4. Run flutter run to launch on a connected device or emulator.
5. Run flutter test to execute the test suite.

Dependencies

Package	Purpose
hive / hive_flutter	Local NoSQL storage for persisting tasks
provider	Lightweight state management via ChangeNotifier
uuid	Generating unique task identifiers
intl	Date formatting and locale-aware display

Project Structure

lib/
  main.dart
  core/
    constants/app_colors.dart
    theme/app_theme.dart
    utils/date_formatter.dart
  data/
    models/task_model.dart
    services/hive_service.dart
  presentation/
    providers/task_provider.dart
    screens/
      splash/splash_screen.dart
      main/main_screen.dart
      home/home_screen.dart
      tasks/task_screen.dart
      add_task/add_task_screen.dart
      profile/profile_screen.dart
    widgets/
      task_card.dart
      custom_bottom_nav.dart
      status_chip.dart
      empty_state.dart

Architecture

The codebase follows a three-layer architecture that separates concerns between core utilities, data operations, and presentation logic.

Core Layer (lib/core/)

Framework-agnostic primitives shared across the app.

• app_colors.dart -- single source of truth for the colour palette. Changing a value here propagates to every widget that references it.
• app_theme.dart -- builds a Material 3 ThemeData from the colour constants. Configures AppBar, InputDecoration, Card, ElevatedButton, and SnackBar themes centrally so screens never define inline styles.
• date_formatter.dart -- static helpers that convert DateTime values into human-readable strings ("Today", "Tomorrow", "In 3 days", etc.).

Data Layer (lib/data/)

Handles persistence and defines the domain model. No Flutter UI imports exist in this layer.

• task_model.dart -- plain Dart class with fields: id, title, description, status (pending/inProgress/completed), priority (low/medium/high), category, dueDate, createdAt, updatedAt. Includes copyWith for immutable updates and an isOverdue getter. Three manually written Hive TypeAdapter classes (Task, TaskStatus, TaskPriority) are co-located here to avoid a build_runner dependency.
• hive_service.dart -- thin wrapper around a Hive Box. Exposes getAllTasks, addTask, updateTask, deleteTask, and clearAll. A static init() registers adapters and opens the box; called once in main() before runApp.

Presentation Layer (lib/presentation/)

Everything the user sees and interacts with.

Provider (task_provider.dart)

A single ChangeNotifier that owns the in-memory task list and mediates between the UI and HiveService. It exposes filtered/sorted task lists (by status and search query), computed statistics (total, completed, pending, in-progress, overdue, completion rate), convenience getters (todayTasks, recentTasks), and async CRUD methods. Each write-through method persists to Hive, reloads the list, and calls notifyListeners so all consumers rebuild.

The provider is created once at the widget tree root via ChangeNotifierProvider in main.dart. Screens consume it with Consumer for rebuilds or context.read() for one-off calls.

Screens

• splash_screen.dart -- animated splash with the brand logo, a subtitle, and a progress bar. Uses three AnimationControllers for staggered effects, then navigates to MainScreen with a fade transition.
• main_screen.dart -- hosts an IndexedStack of four tab screens with a CustomBottomNav. Selecting the Add tab increments a ValueKey to reset form state.
• home_screen.dart -- dashboard with a greeting, stat cards, a gradient progress card, and sections for today's and recent tasks.
• task_screen.dart -- full task list with a search field and horizontal filter chips (All / Pending / In Progress / Completed). Wrapped in RefreshIndicator.
• add_task_screen.dart -- form for creating or editing a task. An optional existingTask parameter switches between create and edit modes. Validates title length and resets all fields after a successful create.
• profile_screen.dart -- user card, completion statistics, and menu items for viewing detailed stats, categories, clearing data, and app info.

Widgets

• task_card.dart -- Dismissible card with swipe-to-delete (confirmation dialog), tap-to-edit, and an animated checkbox for quick status toggling.
• custom_bottom_nav.dart -- four-item bar where the Add button uses a gradient container; the active item expands to reveal its label with animation.
• status_chip.dart -- small coloured badge mapping TaskStatus to a tint and label.
• empty_state.dart -- centered placeholder used when lists are empty or search yields no results.

State Management Rationale

Provider with a single ChangeNotifier was chosen because the app has one shared data source (the task list) and straightforward read/write flows. Every screen either reads the same list with different filters or writes back through the same provider methods. There is no complex event-driven logic that would benefit from a stream-based solution like Bloc, and no need for the scoping features of Riverpod given the flat dependency graph. The result is fewer files, no code generation, and a state layer any Flutter developer can follow without framework-specific knowledge.

Testing

Unit tests for the Task model live in test/widget_test.dart, covering construction defaults, copyWith behaviour, isOverdue logic for open and completed tasks, and enum extension correctness. Run with flutter test.