orderOut

orderOut is a method in Apple's AppKit framework, implemented by NSWindow (and NSPanel) on macOS. It is used to hide a window from the screen by removing it from the window ordering of the application without closing or deallocating the window. The window remains in memory and can be shown again later.

In practice, orderOut is commonly called on a window object, often in response to a user action such as choosing a Hide command. The method accepts a sender parameter, which is typically the object that initiated the action; in code you may pass the sender or nil. Calling orderOut does not terminate the window or the application; it simply makes the window non-visible. If the window was the key window, ordering it out will resign its key status and may cause another window to become key, or the app to have no key window depending on the current window hierarchy.

orderOut is distinct from other window-related actions. For example, minimizing a window using miniaturize places the window in the Dock, whereas orderOut hides it entirely from view. To show a window again, developers typically use orderFront: or makeKeyAndOrderFront: to bring it back to the screen and make it the key window.

In Swift and Objective-C, orderOut is part of the NSWindow API. It is specific to macOS app development with AppKit and does not apply to iOS or UIKit. See also: orderFront:, makeKeyAndOrderFront:, isVisible.