---
title: "menuNeedsUpdate(_:)"
framework: appkit
role: symbol
role_heading: Instance Method
path: "appkit/nsmenudelegate/menuneedsupdate(_:)"
---

# menuNeedsUpdate(_:)

Invoked when a menu is about to be displayed at the start of a tracking session.

## Declaration

```swift
@MainActor optional func menuNeedsUpdate(_ menu: NSMenu)
```

## Parameters

- `menu`: The menu object that is about to be displayed.

## Discussion

Discussion Using this method, the delegate can change the menu by adding, removing, or modifying menu items. If populating the menu will take a long time, implement numberOfItems(in:) and menu(_:update:at:shouldCancel:) instead. Menu item validation occurs after this method is called. If the menu is updated because the user pressed a command key, only the menu item with the matching command key is validated; if the menu is updated because the user opened it, then every menu item is validated.

## See Also

### Handling Tracking

- [numberOfItems(in:)](appkit/nsmenudelegate/numberofitems(in:).md)