nstrackingarea_attemptedfix.mm

//usr/bin/env clang++ $0 -o ${o=`mktemp`} -fmodules -fcxx-modules && echo $o && exec $o $* || exit

@import AppKit;

@interface View : NSView
@property (retain) NSTrackingArea* trackingArea;
@end

@implementation View
- (id)init
{
    if((self = [super initWithFrame:NSZeroRect])) {
        self.trackingArea = nil;
    }
    return self;
}

- (void)mouseEntered:(NSEvent *)event
{
    NSLog(@"mouseEntered");
}

- (void)mouseMoved:(NSEvent *)event
{
    NSLog(@"mouseMoved");
}

- (void)mouseExited:(NSEvent *)event
{
    NSLog(@"mouseExited");
}

- (void)updateTrackingAreas
{
    NSLog(@"updateTrackingAreas");
    [self removeTrackingArea:self.trackingArea];

    if (NSApp.active) {
        NSUInteger trackingOptions = NSTrackingActiveAlways
                | NSTrackingMouseEnteredAndExited | NSTrackingCursorUpdate
                | NSTrackingMouseMoved | NSTrackingInVisibleRect;

        self.trackingArea = [[[NSTrackingArea alloc] initWithRect:NSZeroRect
            options:trackingOptions owner:self userInfo:nil] autorelease];
        [self addTrackingArea:self.trackingArea];
    }

    [super updateTrackingAreas];
}

- (void)applicationDidBecomeActive:(NSNotification *)notification
{
    NSLog(@"applicationDidBecomeActive");
    [self updateTrackingAreas];
}

- (void)applicationDidResignActive:(NSNotification *)notification
{
    NSLog(@"applicationDidResignActive");
    dispatch_async(dispatch_get_main_queue(), ^{
        [self updateTrackingAreas];
    });
}
@end

int main()
{
    @autoreleasepool {
        [NSApplication sharedApplication];
        [NSApp setActivationPolicy:NSApplicationActivationPolicyRegular];

        id appMenu = [[NSMenu new] autorelease];
        [appMenu addItem:[[[NSMenuItem alloc] initWithTitle:@"Quit"
            action:@selector(terminate:) keyEquivalent:@"q"] autorelease]];
        id appMenuItem = [[NSMenuItem new] autorelease];
        [appMenuItem setSubmenu:appMenu];
        NSApp.mainMenu = [[NSMenu new] autorelease];
        [NSApp.mainMenu addItem:appMenuItem];

        NSWindow *window = [[NSWindow alloc] initWithContentRect:NSMakeRect(0, 0, 1200, 300)
            styleMask:NSWindowStyleMaskTitled | NSWindowStyleMaskClosable | NSWindowStyleMaskResizable
            backing:NSBackingStoreBuffered defer:YES];

        window.contentView = [[View alloc] init];
        window.title = @"With mouse over window, quickly ⌘-Tab to Finder without triggering the App Switcher UI, " \
            "then click app window. No mouse enter/exit or mouse move anymore.";

        NSApp.delegate = window.contentView;

        [window center];
        [window makeKeyAndOrderFront:nil];
        [NSApp activateIgnoringOtherApps:YES];
        [NSApp run];
        return 0;
    }

}