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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.

## Relationships

### Inherits From

[`NSObjectProtocol`](/documentation/ObjectiveC/NSObjectProtocol)

[`NSControlTextEditingDelegate`](/documentation/AppKit/NSControlTextEditingDelegate)

[`NSTextFieldDelegate`](/documentation/AppKit/NSTextFieldDelegate)

---

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