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# willAddItemNotification

Posts before the toolbar adds a new item.

```
class let willAddItemNotification: NSNotification.Name
```

## Discussion

The notification item is the `NSToolbar` object that’s about to add the item. The `userInfo` dictionary contains the following information:

|Key                                                                         |Value                                  |
|----------------------------------------------------------------------------|---------------------------------------|
|``doc://com.apple.appkit/documentation/AppKit/NSToolbarUserInfoKey/itemKey``|The `NSToolbarItem` object being added.|

## See Also

[`toolbarWillAddItem(_:)`](/documentation/AppKit/NSToolbarDelegate/toolbarWillAddItem(_:))

Tells the delegate that the toolbar is about to add the specified item.

To observe this notification using Swift concurrency, use [`NSToolbar.WillAddItemMessage`](/documentation/AppKit/NSToolbar/WillAddItemMessage).

---

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