---
title: "setLeftBarButton(_:animated:)"
framework: uikit
role: symbol
role_heading: Instance Method
path: "uikit/uinavigationitem/setleftbarbutton(_:animated:)"
---

# setLeftBarButton(_:animated:)

Sets the custom bar button item, optionally animating the transition to the new item.

## Declaration

```swift
func setLeftBarButton(_ item: UIBarButtonItem?, animated: Bool)
```

## Parameters

- `item`: A custom bar item to display on the left side of the navigation bar.
- `animated`: Specify doc://com.apple.documentation/documentation/Swift/true to animate the transition to the custom bar item when this item is the top item. Specify doc://com.apple.documentation/documentation/Swift/false to set the item immediately without animating the change.

## Discussion

Discussion If two navigation items have the same custom left or right bar button items, those bar button items remain stationary during the transition when the navigation item is pushed or popped.

## See Also

### Specifying custom views

- [centerItemGroups](uikit/uinavigationitem/centeritemgroups.md)
- [leadingItemGroups](uikit/uinavigationitem/leadingitemgroups.md)
- [trailingItemGroups](uikit/uinavigationitem/trailingitemgroups.md)
- [pinnedTrailingGroup](uikit/uinavigationitem/pinnedtrailinggroup.md)
- [titleView](uikit/uinavigationitem/titleview.md)
- [subtitleView](uikit/uinavigationitem/subtitleview.md)
- [largeSubtitleView](uikit/uinavigationitem/largesubtitleview.md)
- [leftBarButtonItems](uikit/uinavigationitem/leftbarbuttonitems.md)
- [leftBarButtonItem](uikit/uinavigationitem/leftbarbuttonitem.md)
- [rightBarButtonItems](uikit/uinavigationitem/rightbarbuttonitems.md)
- [rightBarButtonItem](uikit/uinavigationitem/rightbarbuttonitem.md)
- [setLeftBarButtonItems(_:animated:)](uikit/uinavigationitem/setleftbarbuttonitems(_:animated:).md)
- [setRightBarButtonItems(_:animated:)](uikit/uinavigationitem/setrightbarbuttonitems(_:animated:).md)
- [setRightBarButton(_:animated:)](uikit/uinavigationitem/setrightbarbutton(_:animated:).md)