Web (TeaVM/WebGL) 🌐

The most honest page in the section. The web target (module web, WebLauncher) compiles the app to JavaScript via TeaVM and runs it on a WebGL2 <canvas> (backend gdx-teavm). It is not GWT and it is not an embedded webview: it is the app itself running in the browser.

Build and serve

gradlew :web:webBundle       # (alias: dist)

Generates web/build/webapp/ with index.html, web.js, scripts/howler.js, gdx.wasm.js, and assets/ + assets.txt. Serve it locally:

cd web/build/webapp && python -m http.server 8080
# open http://127.0.0.1:8080/index.html

The WebLauncher does new TeaApplication(new Main(true, cmdline), config).

⚠️ What does NOT work (it is a stub)

On the web, PlatformUtilsWeb implements most features as a stub — the call exists but does nothing useful:

Feature	Behavior on the web
`WebContainer`	`createWebView()` returns `null`
GPS / location	stub (no fix)
Bluetooth / radios	stub (`WirelessState.UNSUPPORTED`)
Biometrics	`AuthResult.ERROR` “Not supported”
Voice (TTS/STT)	`voiceToText` → `onError`
Native maps	not supported
Vibration / battery	stub
File persistence	`Device.homeFolder = null`

Since crossfly-lib (JNI) is not loaded on WebGL (Main.create() skips the SharedLibraryLoader on the WebGL target), everything that depends on native code falls back to the stubs above.

What DOES work

Rendering the full UI (it is the real app on the WebGL2 canvas).
Opening an external URL / dialing: PlatformUtils.instance.view(url) / dial(numero) (via Gdx.net.openURI).
HTTP with restrictions (CORS; Utils.getRemoteFile returns null on failure).

Mandatory pattern: detect and fall back

if (PlatformUtils.instance.createWebView() != null) {
   // Android/iOS/Desktop: embedded webview
} else {
   PlatformUtils.instance.view(url);   // Web: opens in a new tab
}

And check Device.homeFolder == null before attempting to persist a file on the web.

Best practices

Disable/adapt device features on the web (don’t leave buttons that do nothing).
Persistence on the web: use whatever is available in your build (don’t count on homeFolder).
Test by serving the static bundle locally before hosting.

Common mistakes

Assuming WebContainer/GPS/biometrics on the web (they are stubs).
Trying Device.homeFolder + "arquivo" on the web (homeFolder is null → NPE).