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I am seeking for this User Interface(UI) effect --> "Spotlight" a specific IBOutlet (Please see attached Image2.png below) for a week! Explain the "Spotlight" effect : I wish to create is effect similar to NSAlert or beginSheet effect which user cannot click or access the entire window/view until user trigger a button and it back to normal. The whole window/view will becoming darken or gray EXCEPT a specific button I allow my user to interact with. Yet, I found that there is no any trick to create such effect neither in XIB file nor objective-c code. This is urgent for me. Eagerly waiting for your reply. Much Appreciated. (Image 1.png) (Image 2.png)