QuickFill

QuickFill is a localized "Data Vault" for Android that eliminates repetitive typing. Built with the modern Android stack, it leverages the Autofill Framework to inject user-defined snippets (like addresses, ID numbers, and social media boilerplate) directly into input fields across the OS.

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💡 Why QuickFill?

Most productivity apps use Accessibility Services to "read" the screen and paste data. However, modern Android versions are increasingly restricting these services due to security and performance concerns.

QuickFill is built "The Android Way":

• Native Autofill API: Uses the official system-level framework for data injection.
• Privacy First: No Accessibility permissions required. No cloud syncing. Everything stays in your local Room database.
• Context Aware: Automatically filters snippets based on the category of the app you are currently using (Social, Finance, etc.).

🛠 Tech Stack

• Kotlin 2.1.0: Utilizing the latest language features and performance.
• Jetpack Compose: A modern, reactive UI for managing your snippet vault.
• Hilt (Dagger): Dependency injection for a clean, testable architecture.
• Room Database: Local-first persistent storage with Coroutines/Flow support.
• KSP (Kotlin Symbol Processing): Optimized build times for code generation.

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📱 System Requirements & Version Behavior

QuickFill leverages the Android Autofill Framework, which has evolved significantly over different Android versions. The app adapts its UI and logic based on your device's API level.

Minimum Requirements

• Android 8.0 (API 26) or higher: Required for the base Autofill Service functionality.

Version-Specific Behavior

Android Version	Behavior & UI Features
Android 8.0 - 9.0 (API 26-28)	Uses legacy Dropdown UI. Snippets appear in a system-rendered menu below the input field.
Android 11 - 12L (API 30-32)	Supports Inline Suggestions. Snippets appear as "chips" or "pills" inside compatible keyboards (e.g., Gboard). Falls back to dropdown if the keyboard doesn't support inline suggestions.
Android 13+ (API 33+)	Uses the modern Field & Presentation API. Offers the most stable performance and supports high-resolution app icons in the suggestions.

Limitations

• App Compatibility: Some apps (e.g., certain browsers or custom views) do not provide the necessary "Autofill Hints." QuickFill may not be able to detect input fields in these apps.
• Keyboard Support: Inline suggestions (chips above the keyboard) require a compatible Input Method Editor (IME) like Gboard or Samsung Keyboard.
• Package Visibility: On Android 11+, system restrictions limit how apps "see" each other. QuickFill uses a metadata caching strategy to ensure app icons and labels are displayed correctly even with these restrictions.
• Service Activation: Like all password managers, you must manually enable QuickFill in Settings > System > Languages & Input > Autofill service.

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📁 Project Structure

The project uses a feature-based clean architecture:

com.byteutility.dev.quickfill/
├── data/
│   ├── entity/        # Room entities (Snippet, Category, etc.)
│   ├── dao/           # DAO interfaces for database operations
│   └── db/            # Room database configuration
│
├── di/                # Hilt modules (database, repositories, services)
│
├── service/           # AutofillService implementation
│                      # Handles FillRequest & SaveRequest logic
│
├── ui/
│   ├── list/          # Snippet list screen
│   ├── add/           # Add/Edit snippet screen
│   ├── setup/         # Autofill setup guidance screen
│   └── components/    # Reusable Compose UI components
│
└── util/              # App package/category detection
                       # ViewNode traversal & autofill field parsing

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🚀 Getting Started

1. Prerequisites

• Android Studio Ladybug (or newer)
• Android SDK 26 (Oreo) or higher

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2. Installation

1. Clone the repository.
2. Build the project in Android Studio.
3. Install the generated APK on your device.
4. Launch the app.
5. Select QuickFill as your active Autofill provider.

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3. Usage

1. Open the app.
2. Create a new snippet:
   • Add a label (e.g., Work Email)
   • Add a value (e.g., yourname@company.com)
   • Assign a category (e.g., WORK)
3. Save the snippet.

Now, open any app and tap on a text field.
Your saved snippet will appear as a suggestion (either as a keyboard suggestion pill or in a dropdown).

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🚧 Roadmap

• Advanced Filtering Improve package-name mapping to better classify apps currently marked as "Undefined".
• Encryption Integrate a SQLCipher layer with the Room database to securely store sensitive data.
• Search Add quick search functionality within the Snippet List.
• App Specific Support app specific Snippet addition.

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🤝 Contributing

This project started as a personal use-case and serves as a Proof of Concept (PoC).

If you have ideas to improve the Autofill logic or enhance the overall experience, feel free to open an issue or submit a pull request. Contributions are welcome!