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# noteNumberOfItemsChanged()

Informs the receiver that the number of items in its data source has changed.

```
func noteNumberOfItemsChanged()
```

## Discussion

This method allows the receiver to update the scrollers in its displayed pop-up list without actually reloading data into the receiver. It is particularly useful for a data source that continually receives data in the background over a period of time, in which case the `NSComboBox` can remain responsive to the user while the data is received.

See the NSComboBoxDataSource informal protocol specification for information on the messages an `NSComboBox` sends to its data source.

---

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