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  "title" : "NSComboBoxDataSource"
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# NSComboBoxDataSource

```
protocol NSComboBoxDataSource : NSObjectProtocol
```

## Topics

### Instance Methods

[`comboBox(_:completedString:)`](/documentation/AppKit/NSComboBoxDataSource/comboBox(_:completedString:))

Returns the first item from the pop-up list that starts with the text the user has typed.

[`comboBox(_:indexOfItemWithStringValue:)`](/documentation/AppKit/NSComboBoxDataSource/comboBox(_:indexOfItemWithStringValue:))

Returns the index of the combo box item matching the specified string.

[`comboBox(_:objectValueForItemAt:)`](/documentation/AppKit/NSComboBoxDataSource/comboBox(_:objectValueForItemAt:))

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

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

Returns the number of items that the data source manages for the combo box.


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