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# tabBar(_:willBeginCustomizing:)

Sent to the delegate before the customizing modal view is displayed.

```
optional func tabBar(_ tabBar: UITabBar, willBeginCustomizing items: [UITabBarItem])
```

## Parameters

`tabBar`

The tab bar that is being customized.

`items`

The items on the customizing modal view.

## Discussion

Use the [`beginCustomizingItems(_:)`](/documentation/UIKit/UITabBar/beginCustomizingItems(_:)) method of [`UITabBar`](/documentation/UIKit/UITabBar) to display the customizing modal view and begin the customizing mode.

---

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