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# NSComboBoxDelegate

A set of optional methods implemented by delegates of combo box objects.

```
protocol NSComboBoxDelegate : NSTextFieldDelegate
```

## Topics

### Manipulating the selection

[`comboBoxSelectionDidChange(_:)`](/documentation/AppKit/NSComboBoxDelegate/comboBoxSelectionDidChange(_:))

Informs the delegate that the pop-up list selection has finished changing.

[`comboBoxSelectionIsChanging(_:)`](/documentation/AppKit/NSComboBoxDelegate/comboBoxSelectionIsChanging(_:))

Informs the delegate that the pop-up list selection is changing.

[`comboBoxWillDismiss(_:)`](/documentation/AppKit/NSComboBoxDelegate/comboBoxWillDismiss(_:))

Informs the delegate that the pop-up list is about to be dismissed.

[`comboBoxWillPopUp(_:)`](/documentation/AppKit/NSComboBoxDelegate/comboBoxWillPopUp(_:))

Informs the delegate that the pop-up list is about to be displayed.


---

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