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# NSComboBoxCellDataSource

```
protocol NSComboBoxCellDataSource : NSObjectProtocol
```

## Topics

### Instance Methods

[`comboBoxCell(_:completedString:)`](/documentation/AppKit/NSComboBoxCellDataSource/comboBoxCell(_:completedString:))

Returns the item from the combo box’s pop-up list that matches the text entered by the user.

[`comboBoxCell(_:indexOfItemWithStringValue:)`](/documentation/AppKit/NSComboBoxCellDataSource/comboBoxCell(_:indexOfItemWithStringValue:))

Invoked by an `NSComboBoxCell` object to synchronize the pop-up list’s selected item with the text field’s contents.

[`comboBoxCell(_:objectValueForItemAt:)`](/documentation/AppKit/NSComboBoxCellDataSource/comboBoxCell(_:objectValueForItemAt:))

Returns the object that corresponds to the item at the given index in the combo box cell.

[`numberOfItems(in:)`](/documentation/AppKit/NSComboBoxCellDataSource/numberOfItems(in:))

Returns the number of items managed for the combo box cell by your data source object.


---

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