Custom NSStatusItem with custom view - Use NSWindow, NSView, custom NSMenuItem?

I'm trying 开发者_开发问答to create a LSUIElement app that behaves like Spotlight, CoverSutra and other apps of that type. I managed to create a custom NSStatusItem, which popups up an NSWindow but the problem is that the app that currently has focus will the focus to my custom NSWindow.

I've based myself on Matt Gemmell's example (http://mattgemmell.com/2008/03/04/using-maattachedwindow-with-an-nsstatusitem)

For example, if you're in Safari and click on the Spotlight icon, the current Safari window does not gray out and keeps focused. When you press ESC in Spotlight, the focus is back to the Safari window.

I haven't managed to do this with my custom NSWindow. I have to click back on a window to set focus back to it.

So I'd like to know which route to go to achieve this. Is the solution a NSWindow, NSPanel, NSMenu with a custom NSMenuItem?

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Use NSPanel and NSNonactivatingPanelMask as styleMask or tick the option in IB.