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  "title" : "updateWindows()"
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# updateWindows()

Sends an [`update()`](/documentation/AppKit/NSWindow/update()) message to each onscreen window.

```
func updateWindows()
```

## Discussion

This method is invoked automatically in the main event loop after each event when running in `NSDefaultRunLoopMode` or `NSModalRunLoopMode`. This method is not invoked automatically when running in `NSEventTrackingRunLoopMode`.

When this method begins, it posts an [`willUpdateNotification`](/documentation/AppKit/NSApplication/willUpdateNotification) to the default notification center. When it successfully completes, it posts an [`didUpdateNotification`](/documentation/AppKit/NSApplication/didUpdateNotification).

## See Also

[`func applicationDidUpdate(Notification)`](/documentation/AppKit/NSApplicationDelegate/applicationDidUpdate(_:))

Tells the delegate that the app’s windows did update.

[`func applicationWillUpdate(Notification)`](/documentation/AppKit/NSApplicationDelegate/applicationWillUpdate(_:))

Tells the delegate that the app is about to update its windows.

[`func update()`](/documentation/AppKit/NSWindow/update())

Updates the window.


---

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