NSWindow shows an icon with the window path; how can I remove it?

The title explains my problem. Here there are two images:

Icon

http://cl.ly/ACYq/icon.png

The path when 开发者_如何学JAVAI click the icon

http://cl.ly/ABMM/icon2.png

What have I done to set this? How can I delete this icon?

If there's an icon, it means your window has a represented URL.

You can use the setRepresentedURL: method to change or disable it (passing nil).