dejaos-app-dev-sdk2-0

name	dejaos-app-dev-sdk2-0
description	Build, modify, or review DejaOS SDK 2.0 embedded JavaScript applications. Use when working with DejaOS SDK 2.0 app projects, dxmodules, QuickJS workers, LVGL UI via dxUi, app.dxproj component selection, UIManager page flows, UART, SQLite, MQTT, HTTP, facial recognition, watchdogs, device resources, or embedded runtime constraints. Use when this capability is needed.
metadata	{"author":"DejaOS"}

DejaOS SDK 2.0 App Development

Use this skill for DejaOS SDK 2.0 embedded JavaScript apps. DejaOS runs on QuickJS with native dxmodules wrappers for UI, hardware, storage, network, MQTT, HTTP, audio, face recognition, UART, watchdog, and related device features.

First Checks

1. Confirm the target device model before changing project structure or app.dxproj: DW200_V20, VF105_V12, VF203_V12, VF202_V12, or VF114_V12.
2. Inspect the existing app.dxproj and dxmodules/ before importing a component.
3. If a required dxmodules/*.js file is missing, tell the user to enable the component in app.dxproj and install modules with the DejaOS VSCode plugin.
4. Treat dxmodules/ as vendor code: call it, but do not modify it.
5. Keep app code under src/, resources under resource/, and runtime data under /app/data.
6. Use absolute runtime resource paths such as /app/code/resource/logo.png.

Project Rules

• Use dxLogger for logging; do not use console.log in app code.
• Wrap hardware, network, filesystem, database, UART, timer, and worker-boundary code in try/catch.
• Keep main.js focused on initialization and worker creation. Put UI, serial loops, face recognition loops, and long-running business logic in workers.
• Create workers with dxEventBus.newWorker(...) instead of native QuickJS worker APIs.
• Remember that each worker is single-threaded. dxStd.setTimeout and dxStd.setInterval are pseudo-async inside the same worker.
• Prefer small objects and bounded loops. DejaOS devices have limited memory and CPU.
• Use imports relative to file depth, for example ../../dxmodules/dxLogger.js; there is no Node-style node_modules resolution.

UI Rules

• Put UI in a dedicated UI worker.
• If UI text includes Chinese or other non-English text, ensure a TTF font exists, usually /app/code/resource/font/font.ttf.
• Prefer UIManager.font(size, style) to avoid repeatedly creating font objects.
• Use assets/UIManager.js as the standard single-screen, multi-page UI manager template when a project does not already have one.
• A UI page should expose init(), return its root View, and may implement onShow(data) and onHide().
• uiButton does not have a direct text property. Create a Label inside the button.
• uiImage is not clickable by itself. Wrap it in a transparent View and register the click on the wrapper.
• For topmost overlays, use dxui.Utils.LAYER.TOP.
• For uiView, call padAll(0) and usually scroll(false) when doing exact layout.
• Match image control sizes to image asset sizes because uiImage does not automatically scale by default.

Common Components

• Base modules: dxLogger, dxStd, dxOs, dxDriver, dxMap, dxEventBus, dxCommonUtils.
• UI: dxUi.
• Storage: dxSqliteDB for relational data; dxKeyValueDB for simple key-value data.
• Network: dxNetwork, dxHttpClient, dxHttpServer, dxMqttClient.
• Hardware: dxUart, dxGpio, dxGpioKey, dxPwm, dxNfc, dxBarcode.
• System: dxWatchdog, dxNtp, dxOta, dxConfiguration, dxAudio.

Task Guidance

When creating a new app:

1. Start from the target model's app.dxproj.
2. Include only base modules by default; add dxUi only when UI is needed; add hardware/network modules only when required.
3. Create src/main.js.
4. If UI is needed, create src/uiWorker.js, copy or adapt assets/UIManager.js, register pages, and call dxui.handler() in a short interval.
5. Put resources in resource/, especially fonts and images.

When modifying an existing app:

1. Read nearby code first and follow existing worker boundaries.
2. Check whether the needed component is already present in dxmodules/.
3. Preserve existing page manager, event bus topics, and data directory conventions unless the user asks for a refactor.
4. Verify JavaScript syntax with the available runtime when possible.

When reviewing DejaOS code, prioritize:

• Missing try/catch around device and worker boundary code.
• Incorrect relative imports into dxmodules.
• UI code running in the main worker.
• Direct console.log.
• Missing font handling for Chinese UI.
• Resource paths that are not runtime absolute paths.
• uiButton text set directly instead of via a child Label.
• Click handlers attached directly to uiImage.
• Long loops or heavy work in UI workers.

Bundled Resources

• references/dejaos-guide.md: English DejaOS SDK 2.0 development guide with module notes and code templates. Read when the task involves unfamiliar DejaOS modules or when building a new app structure.
• references/fitlock-patterns.md: English patterns distilled from a production-style FitLock cabinet app in this workspace. Read when designing larger apps with UI, MQTT, SQLite, face recognition, lock control, pending event queues, or multi-worker coordination.
• assets/UIManager.js: Reusable UIManager page-stack template.
• assets/DW200_V20-app.dxproj: Example app.dxproj for DW200_V20.
• assets/VF105_V12-app.dxproj: Example app.dxproj for VF105_V12.

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Source: DejaOS/DejaOS — distributed by TomeVault.