# fast-code-scanner

**Repository Path**: captainwilson/fast-code-scanner

## Basic Information

- **Project Name**: fast-code-scanner
- **Description**: G520低功耗设备上优化的快速qrcode，barcode扫码器
- **Primary Language**: Unknown
- **License**: Not specified
- **Default Branch**: master
- **Homepage**: None
- **GVP Project**: No

## Statistics

- **Stars**: 0
- **Forks**: 0
- **Created**: 2026-04-14
- **Last Updated**: 2026-04-14

## Categories & Tags

**Categories**: Uncategorized

**Tags**: None

## README

# scan_standalone

Standalone Android QR/barcode scanner app built with Kotlin, Android Views, and ZXing.

## Overview

This project is a small single-module Android application focused on one job: scanning QR codes and common 1D barcodes, showing the decoded result, and letting the user copy it to the clipboard.

The app appears designed for a **landscape-only, large-screen / device-style scanning experience**:

- fullscreen UI
- keep-screen-on behavior
- many `values-swNNNdp` dimension buckets for different screen widths
- DPAD/Enter key handling inside the scan screen

## Features

- Requests camera permission at runtime
- Launches a dedicated scan screen with ZXing embedded scanner
- Supports these barcode formats:
  - `QR_CODE`
  - `EAN_13`
  - `EAN_8`
  - `UPC_A`
  - `UPC_E`
  - `CODE_128`
  - `CODE_39`
- Shows:
  - scan state
  - decoded content
  - barcode format
- Lets the user copy the latest result to the clipboard
- Supports flashlight toggle and DPAD-based zoom/toggle behavior in the capture screen
- Includes localized string resources:
  - default Chinese
  - English
  - German
  - Spanish
  - Portuguese

## Tech stack

- Kotlin
- Android Views + ViewBinding
- ConstraintLayout
- Material Components
- ZXing via `com.journeyapps:zxing-android-embedded:4.3.0`
- Android Gradle Plugin `8.1.3`
- Kotlin plugin `1.9.0`

## Android config

- `applicationId`: `com.goolton.scan`
- `namespace`: `com.goolton.scan`
- `compileSdk`: `33`
- `targetSdk`: `33`
- `minSdk`: `28`
- `versionName`: `1.0.0`

## Project structure

```text
scan_standalone/
+-- app/
|   +-- src/main/java/com/goolton/scan/
|   |   +-- ScanActivity.kt
|   |   \-- ScanCodeActivity.kt
|   +-- src/main/res/
|   |   +-- layout/activity_scan.xml
|   |   +-- drawable/
|   |   +-- values/
|   |   +-- values-en/
|   |   +-- values-de/
|   |   +-- values-es/
|   |   +-- values-pt/
|   |   \-- values-sw*/        # screen-width-specific dimensions
|   +-- build.gradle.kts
|   \-- proguard-rules.pro
+-- gradle/
+-- build.gradle.kts
+-- settings.gradle.kts
\-- gradlew.bat
```

## Main flow

### `ScanActivity`

The launcher activity:

- inflates the main result screen
- requests camera permission
- starts scanning immediately when permission is available
- stores the latest decoded text + format in memory
- lets the user rescan or copy the last result

### `ScanCodeActivity`

Custom scan/capture activity built on top of ZXing `CaptureActivity`:

- uses ZXing's capture layout
- configures autofocus / infinity focus based on device capability
- adds flashlight controls
- handles hardware keys:
  - `DPAD_LEFT` / `DPAD_RIGHT`: zoom
  - `DPAD_CENTER` / `ENTER`: toggle flashlight

## Build requirements

To build this project locally, you should have:

- **JDK 17 or newer** for AGP 8.1.x
- Android SDK Platform 33
- Android build tools installed through Android Studio / SDK Manager

Create your own `local.properties` if needed:

```properties
sdk.dir=/path/to/Android/Sdk
```

## Build commands

From the project root:

```bash
./gradlew assembleDebug
./gradlew testDebugUnitTest
./gradlew lintDebug
```

On Windows:

```powershell
.\gradlew.bat assembleDebug
.\gradlew.bat testDebugUnitTest
.\gradlew.bat lintDebug
```

## Permissions

The app requests:

- `android.permission.CAMERA`

It also declares:

- camera hardware required
- autofocus optional

## Privacy / behavior notes

- The app does **not** include networking code.
- Scan results are displayed locally and can be copied to the clipboard.
- There is no persistence layer in the current codebase for saving scan history.
- `android:allowBackup="true"` is enabled; revisit this if future versions store sensitive data.

## Current repo assessment

### Strengths

- Very small and easy-to-understand codebase
- Focused single-purpose UX
- Minimal permission surface
- No backend dependency in current implementation
- Good fit for embedded / kiosk-like hardware thanks to landscape + key handling

### Gaps / risks

- No unit tests or instrumentation tests are checked into the repo
- Release build hardening is minimal:
  - `isMinifyEnabled = false`
  - `proguard-rules.pro` is effectively empty
- Permission denial flow does not guide the user to system settings when permission is permanently denied
- Scan result is kept only in memory and is not restored after process death
- Flash controls in the capture screen are implemented with transparent overlay buttons, which may be device-specific and should be validated on target hardware

## Suggested next improvements

1. Add unit tests for scan state transitions
2. Add basic instrumentation / smoke tests
3. Improve permission UX for "Don't ask again"
4. Decide whether release builds should enable shrinking / obfuscation
5. Document target hardware and expected input methods
6. Consider saving recent scan history if product requirements need it

## Useful files

- `app/src/main/java/com/goolton/scan/ScanActivity.kt`
- `app/src/main/java/com/goolton/scan/ScanCodeActivity.kt`
- `app/src/main/res/layout/activity_scan.xml`
- `app/src/main/AndroidManifest.xml`
- `app/build.gradle.kts`