smooth_window_close 0.2.0

Hide Flutter Windows apps before graceful asynchronous shutdown.

smooth_window_close

Responsive, graceful shutdown for Flutter Windows applications.

Flutter desktop apps often intercept native close events to save state, close databases, stop sockets, or destroy tray resources. Awaiting that work while the Flutter window remains visible can leave a frozen final frame on screen.

smooth_window_close hides the Windows window first, performs asynchronous state saving and cleanup, then allows and destroys the window. It uses window_manager; no custom native runner changes are required.

Installation

Published dependency:

dependencies:
  smooth_window_close: ^0.2.0

Local sibling package:

dependencies:
  smooth_window_close:
    path: ../smooth_window_close

Basic usage

runApp(
  SmoothWindowCloseScope(
    onSaveState: saveWindowState,
    onCleanup: shutdownServices,
    onError: (error, stackTrace) {
      logger.warning('Shutdown failed', error, stackTrace);
    },
    child: MaterialApp(home: HomePage()),
  ),
);

The scope initializes and disposes its closer automatically. Keep windowManager.ensureInitialized() in main() before runApp().

Close-to-tray

No tray package is required. Supply application state through a callback:

SmoothWindowCloseScope(
  shouldCloseToTray: () => settings.closeToTray,
  onSaveState: saveWindowBounds,
  onCleanup: () async {
    await closeChildWindows();
    await destroyTray();
  },
  child: MaterialApp(home: HomePage()),
);

A normal X or Alt+F4 request hides the window, saves state, and returns when shouldCloseToTray is true. Your tray integration remains responsible for showing the window again.

Explicit Exit

Use exit() for File → Exit, tray Exit, or a Quit button:

await SmoothWindowCloseScope.of(context).exit();

exit() always terminates, even when close-to-tray is enabled.

Use handleCloseRequest() only when manually forwarding a normal close request. Native X and Alt+F4 events are already handled after initialize().

Operation order

Windows exit:

hide → save state → cleanup → setPreventClose(false) → destroy

Windows close-to-tray:

hide → save state → return

The reentrancy guard is set before the first asynchronous operation. Repeated close events cannot run cleanup concurrently. Callback failures are reported through onError; remaining shutdown steps continue so a failed cleanup does not leave an invisible process running indefinitely.

Keep callbacks limited to work that genuinely must finish before process exit.