---
title: lynnswap/floatingaccessorykit
framework: Swift Package Catalog
role: article
path: packages/lynnswap/floatingaccessorykit
---

# lynnswap/floatingaccessorykit

`FloatingAccessoryKit` makes it simple to add floating accessories to UIKit containers. It currently provides a tab bar accessory controller for `UITabBarController`.

## Requirements

- iOS 18.0+ - iPhone only - Swift 6.2

## Usage

```swift import FloatingAccessoryKit import UIKit

final class MainTabBarController: UITabBarController {     override func viewDidLoad() {         super.viewDidLoad()

let button = UIButton(type: .system)         button.setImage(UIImage(systemName: "plus"), for: .normal)         button.widthAnchor.constraint(equalTo: button.heightAnchor).isActive = true

floatingAccessoryController.setContentView(             button,             position: .trailing,             animated: false         )     } } ```

## Content Updates

Layout-driven content-size changes are measured automatically. If you change a view's intrinsic size, bounds, constraints, or subview hierarchy explicitly, perform the changes through the accessory controller:

```swift floatingAccessoryController.performContentUpdate {     button.setTitle("Updated", for: .normal)     button.invalidateIntrinsicContentSize() } ```

`performContentUpdate` runs the mutations and remeasurement in one UIKit update transaction. The default update animates with UIKit timing and respects Reduce Motion. Pass `animated: false` when the change should be applied immediately. The content view remains installed, and its position and visibility are preserved.

## Accessory Background

The view passed to `setContentView` is foreground content. Do not add your own capsule or material background.

On iOS 26+, FloatingAccessoryKit uses the native `UITabAccessory` presentation without adding another background. On iOS 18, FloatingAccessoryKit adds a matching overlay background around the content.

## Tab Bar Minimization

On iOS 26+, use UIKit's `tabBarMinimizeBehavior` when you want the tab bar to minimize while scrolling.

On iOS 18, toggle the tab bar through `floatingAccessoryController.setTabBarHidden(_:animated:)`. `FloatingAccessoryKit` then updates the accessory and the tab bar from the same coordination boundary. When the tab bar is hidden, tapping or long-pressing the empty area where the tab bar was shown restores it.

```swift if #available(iOS 26.0, *) {     tabBarMinimizeBehavior = .onScrollDown } ```

For iOS 18, implement your own scroll policy, then call `floatingAccessoryController.setTabBarHidden(_:animated:)` when that policy decides to hide or show the tab bar.

```swift func scrollViewDidScroll(_ scrollView: UIScrollView) {     guard #unavailable(iOS 26.0) else {         return     }

floatingAccessoryController.setTabBarHidden(         shouldHideTabBar,         animated: true     ) } ```

## Migration

### v0.3.0

These notes apply when upgrading from `v0.2.x` or earlier to `v0.3.0`.

- Replace `TabBarAccessoryController(tabBarController:)` with the controller owned by the host:

```swift   let accessoryController = tabBarController.floatingAccessoryController   ```

- Replace `setContent(_:position:animated:)` with the operation that matches the change:

```swift   accessoryController.setContentView(view, position: .trailing, animated: true)   accessoryController.setPosition(.center, animated: true)   accessoryController.setHidden(true, animated: true)   accessoryController.removeContent(animated: true)   ```

- `position` and `isHidden` now remain unchanged when content is removed. Installing content without a `position` also preserves the current position. - Replace resubmitting the same view for measurement with a content update transaction:

```swift   accessoryController.performContentUpdate {       view.invalidateIntrinsicContentSize()   }   ```

Put every explicit layout-affecting mutation in the closure. Layout-driven changes are still measured automatically. The transaction animates by default with UIKit timing and respects Reduce Motion. - `removeContent(animated:)` detaches the consumer view before returning. Any remaining removal animation uses a snapshot. - On iOS 18, replace direct calls to `UITabBarController.setTabBarHidden(_:animated:)` with `floatingAccessoryController.setTabBarHidden(_:animated:)` so the overlay is updated in the same operation.

## Package Metadata

Repository: lynnswap/floatingaccessorykit

Default branch: main

README: README.md