Web links previously launched a separate Chrome/Edge kiosk process, which
caused the whole class of bugs in the tracker: the browser opening behind the
player, being handed off to an already-running instance and exiting instantly,
fighting for foreground/z-order, and leaking msedge.exe/chrome.exe processes
that were never closed.
WebView2 renders as a CHILD HWND of Kivy's own SDL window instead, so there is
no separate top-level browser to open behind the player, nothing to hand the
URL off to, no z-order contest, and no leaked browser process.
Windows/webview2_browser.py
- Environment -> controller -> navigate, driven through pythonnet.
- Async .NET Tasks are polled from Kivy's Clock. Calling GetAwaiter()
.GetResult() would deadlock: the continuation needs the same thread's
message pump.
- The controller is a .NET IntPtr, not a Python int (CreateAsync overloads
do not match otherwise).
- NavigationCompleted is tracked so a page that never loads can be told
apart from one that did. This matters on a closed network: an unreachable
host paints a Chromium error page, and without this the player would show
a blank/error screen for the item's whole slot instead of skipping it.
- is_alive() reports True while starting up. Start-up is async, so a
controller that does not exist yet is not a dead browser; treating it as
one made the first web link after a cold start be skipped instantly.
Windows/webview2_runtime.py
- Detects the Runtime (registry pv value, SDK probe as fallback) and
installs it silently when missing, unelevated, which produces a per-user
install and therefore never raises a UAC prompt on the signage display.
- Success is decided by RE-READING the installed version, not by the
installer exit code: Edge Update returns a non-zero HRESULT
(-2147219416) when the Runtime is already current, which is not a failure.
- On a closed network the online bootstrapper can never succeed, so it fails
fast with an actionable message instead of hanging for the full timeout.
- Failed attempts are cooldown-gated so a broken machine does not re-run an
installer on every start.
Offline hardening
- Browser arguments disable component updates, field trials, safe-browsing
list fetches, translate and other internet chatter. On an isolated LAN
each of those would otherwise have to time out, costing start-up latency.
Pages on the local server are unaffected.
Engine order (best first): WebView2 -> CEF -> Chrome/Edge subprocess. CEF has
no wheels past Python 3.9 so it is dormant on this build; the subprocess engine
remains only as a last resort.
Also fixes the reason the Windows adapters were never used at all:
SignagePlayer.__init__ assigned self.weblink_adapter_factory = None, which
shadowed the CLASS attribute that run_win.py injects. play_weblink() therefore
fell back to the generic adapter, whose find_browser() uses shutil.which() and
finds nothing on Windows because Chrome/Edge are not on PATH. The instance
attribute is now only set when the class attribute is absent.
Verified: windows/test_webview2_embed.py, test_webview2_navigation.py and
test_webview2_offline.py all pass (a locally served page renders with all
internet traffic disabled), and the packaged exe reports
"weblink_launch engine=webview2-embedded" -> "weblink_launched" on every cycle
with no leaked browser processes.
Web links were implemented three times (main.py subprocess, run_win.py
subprocess + Win32 overlay, cef_browser.py embedded CEF), each owning its own
process handle, watchdog and teardown. That ambiguity caused leaked browsers,
skipped items, lost foreground and blank screens when a page failed to load.
Replace all three with a single owner in src/weblink_session.py:
- WeblinkSession: validate -> launch -> verify -> watch -> teardown.
Generation-tokened so stale callbacks are ignored, idempotent close(),
atexit-safe, never more than one browser alive.
- WeblinkAdapter: the only platform-specific part (launch / wait_visible /
is_alive / teardown / prewarm). Platform layers inject engines through
SignagePlayer.weblink_adapter_factory.
- ChromiumSubprocessAdapter: default engine (Pi chromium, Windows chrome/msedge).
- InteractionWatcher: decides when an item is finished.
- WebInputSources: /dev/input/event* (Linux) plus a GetCursorPos pointer tap
(needed on Windows for embedded CEF, which has no child process).
Interaction model: web links are an interactive surface, not timed media.
The player advances only when the configured duration has elapsed AND the
viewer has not interacted for 10s, measured from the most recent interaction.
A touch in the final seconds of a slot therefore pushes the advance 10s past
that touch, and each further touch pushes it again, so a page is never pulled
out from under someone using it. An untouched page still advances on schedule.
A drag burst counts as one interaction but the countdown tracks its last event,
so an item cannot be cut off mid-gesture. max_dwell (duration x factor, floored
by min_max_dwell) is an absolute backstop against a wedged browser or a jammed
touchscreen.
Verified start-up: the visibility wait runs on the watcher thread, never on
Kivy's main thread. If the browser window never appears the item is reported
failed and skipped, instead of resetting the error counter and leaving a black
screen up for the whole duration.
Config: new "weblink" block in config/app_config.json (engine,
interaction_postpone, interaction_debounce, interaction_grace,
max_dwell_factor, min_max_dwell, launch_timeout, prewarm) with safe defaults,
so an absent block still works.
Also add weblink_session to the PyInstaller hiddenimports so the frozen exe
bundles the new module.
- get_playlists_v2: pass through weblink items without download, preserve type
- main.py: render weblink items fullscreen via Chromium kiosk overlay with cleanup on next/pause/stop
- main.py: fix unbounded recursion when playlist media is missing/invalid by scheduling retries via Clock (keeps standard playlist cycling offline)
- docs: add PLAYER_WEBLINK_INTEGRATION.md
ske087
Kiwy Signage Player