Dropbox's built-in notification system

Does anyone know how to create a notify window like the dropbox's built-in notification system in cocoa?

window like

Links about the notificatio开发者_如何学JAVAn system

Thanks

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The answer is in your question: Dropbox is using Growl for notifications. Here is Growl developer documentation. Oh, and don't tell the Growl developers that the nofitication system is built-in. ;-)

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Ok I found the way to implementation this. Do not use the Interface Builder,objective-c code instead.Rewrite the NSWindow as you want.