Menu-bar apps: window close-policy (hide instead of quit) and tray commands for app show/quit

Version: native 0.5.3 (commit 57bf56b) · macOS

We're building a menu-bar music player (internet-radio client: status_item_fn tray, audio via fx.playAudio). Two lifecycle behaviors of that app class currently have no seam, and both need the same kind of host-side support. Filing together since they're two halves of one pattern.

1. Closing the last window always quits the app

windowWillClose in the AppKit host emits shutdown when windows.count == 0. For a media app, the red close button killing playback is wrong — the expected shape is Spotify-like: close hides the window, the audio and the tray keep running, and a Dock-icon click brings the window back. There's currently no policy hook: no windowShouldClose on the delegate and no manifest option.

Proposal: a declarative policy on ShellWindow / WindowDescriptor, e.g.

.close_policy = .quit (default) | .hide_app | .hide_window

.hide_app mapping cleanly onto [NSApp hide:] (Dock click restores for free, Cmd+Q/SIGTERM/AppleScript quit still terminate normally).

Our local patch (running fine for a while now) is a windowShouldClose: on NativeSdkWindowDelegate that hides the app when a status item is installed and the closing window is "main":

- (BOOL)windowShouldClose:(NSWindow *)sender {
    (void)sender;
    if (self.host.statusItem == nil) return YES;
    NSString *label = self.host.windowLabels[@(self.windowId)];
    if ([label isEqualToString:@"main"]) {
        [NSApp hide:nil];
        return NO;
    }
    return YES;
}

2. Tray items can't open (unhide) or quit the app

Once close-hides exists, the tray needs "Open player" and "Quit" rows — but tray commands dispatch into update, and the model has no channel to [NSApp unhide:] / [NSApp activate...] / [NSApp terminate:]. (The status_item docs example even shows .command = "app.quit", but nothing handles that name.)

Proposal: well-known built-in tray commands the host handles before (or instead of) forwarding — e.g. "app.show" → unhide + activate, "app.quit" → terminate — mirroring what the docs already imply.

Our local patch reserves item ids in trayMenuItemClicked::

    if (menuItem.tag == 100) {          /* "Open player" */
        [NSApp unhide:nil];
        [NSApp activateIgnoringOtherApps:YES];
    } else if (menuItem.tag == 101) {   /* "Quit" */
        [NSApp terminate:nil];
        return;
    }

Both patches together give the full menu-bar-app close/reopen/quit loop; we'd love to drop them for first-class options. Happy to send PRs if the proposed shapes look right.

Start with the AppKit host's NativeSdkWindowDelegate and its windowWillClose/windowShouldClose behavior, then trace ShellWindow or WindowDescriptor and the trayMenuItemClicked: entry point. Compare the status_item documentation example with the host command dispatch. Done means a declared close policy and built-in show/quit commands support the described hide, reopen, and termination flows without breaking default quitting.