FlipClock · Android (Jetpack Compose)

WeChat MiniProgram wx1b56c32a1e5c1714 rewritten as a native Android app using Jetpack Compose + Material 3.

Stack

• Kotlin 2.3.20, AGP 9.0.1
• Jetpack Compose (BOM 2026.03.01) + Material 3
• Navigation 3 with typed keys (kotlinx.serialization)
• Coroutines + StateFlow for reactive state
• Min SDK 26, target SDK 36

Project layout

app/src/main/java/com/example/flipclock/
├── MainActivity.kt            # Entry point, sets up theme + navigation
├── Navigation.kt              # NavDisplay wiring, shared BleManager
├── NavigationKeys.kt          # @Serializable NavKeys (Home, AddClockKey)
├── theme/                     # Material 3 color/typography/shape
├── data/
│   ├── Alarm.kt               # Alarm entity + RepeatMode enum
│   └── DeviceState.kt         # Aggregate device state + FeatureTab
├── ble/
│   ├── Opcodes.kt             # Protocol constants transcribed 1:1 from JS
│   ├── BleCodec.kt            # ByteArray packet builders
│   ├── BleManager.kt          # Transport interface
│   └── FakeBleManager.kt      # In-memory impl (decodes writes back onto state)
└── ui/
    ├── components/
    │   ├── FlipClockDisplay.kt   # Split-flap digit + HH:MM row
    │   └── CommonCards.kt        # FlipCard, NoticeBanner, SettingsRow
    ├── home/
    │   ├── HomeScreen.kt         # Scaffold, clock, status card, tabs
    │   ├── HomeViewModel.kt      # Bridges UI events to BleManager
    │   ├── AlarmSection.kt       # 闹钟
    │   ├── TomatoSection.kt      # 橘子时钟
    │   ├── DrinkWaterSection.kt  # 喝水提醒
    │   ├── SoundSection.kt       # 四档音量滑块
    │   └── CalibrationSection.kt # 校时 / 主页展示 / 轮子偏移 / OTA
    └── addclock/
        └── AddClockScreen.kt     # 新增 / 编辑 / 喝水闹钟

BLE protocol

Every opcode and packet layout from the original MiniProgram is kept byte-for-byte in ble/Opcodes.kt and ble/BleCodec.kt. Swap FakeBleManager for a real BluetoothGatt-backed implementation and the UI keeps working unchanged.

Opcode	Purpose	Payload
0	Set volume	byte channel + byte 0..100
2	Sync time	uint32 epoch (LE)
5	Add / update alarm	12-byte alarm struct
6	Delete alarm	uint32 alarmSn
8	Wheel offset	int8 left + int8 right
9 / 10	Enter / exit production	—
11	Close connection	—
12	Factory reset	—
13	Wipe a flap page	byte page
34/35/37	OTA header/chunk/commit	see BleManager.startOta

Building

cd android
./gradlew :app:assembleDebug          # produces app/build/outputs/apk/debug/app-debug.apk
./gradlew :app:installDebug           # deploy to connected device / emulator

Or open the android/ folder in Android Studio and hit ▶.

What's still TODO

• Real BLE scan/connect/GATT pipeline (BleManager implementation against BluetoothLeScanner / BluetoothGatt).
• OTA end-to-end wiring on the home screen (the codec is in place).
• DrinkWater "enable" switch + interval picker round-trip.
• Persist user preferences (DataStore) so state survives device disconnects.
• Runtime permission prompts for BLUETOOTH_SCAN / BLUETOOTH_CONNECT.

The UI, theming, data models, and protocol encoders are complete and verified against the original MiniProgram source.