macOS Show Window without activating (keep application below it active)

[wesleyh]

I need to show a window (without title bar) above third party applications without my window taking focus.

I have tried using an NSPanel and setting enabling non-activating, but that didn't help.

I tried orderFront:self, but that didn't help either.

I always needed to add [NSApp activateIgnoringOtherApps:YES]; because the window wouldn't show otherwise.

I have here a sample project for just this functionality:
http://users.telenet.be/prullen/TopW2.zip

UIElement is set to true in the application's plist file, so there is no dock. You can activate the window by pressing ALT + SPACE at the same time. You will see that the app below it looses focus. Any thoughts on how to fix this? I've seen other apps do it so I know it's possible.

Edit: here's the code so far. Remember the window is a non-activating NSPanel. I still need that last NSApp activateIgnoringOtherApps line or otherwise it doesn't display. But of course that makes the window the active one.

 _windowController = [[MyWindowController alloc] initWithWindowNibName:@"MyWindowController"];

    [[_windowController window] setLevel:NSNormalWindowLevel+1];
    [[_windowController window] orderFrontRegardless];

    [_windowController showWindow:self];

   [NSApp activateIgnoringOtherApps:YES];

I've also subclassed NSPanel and added two methods:

- (BOOL)canBecomeKeyWindow
{
    return NO;
}

- (BOOL)canBecomeMainWindow
{
    return NO;
}

(I also tried canBecomeKeyWindow return YES and several other levels (for setLevel).

Any ideas?