UIHostingController

The UIHostingController is a class introduced in iOS 13 and later versions of Apple’s iOS operating system, designed to facilitate the integration of SwiftUI views into UIKit-based applications. It serves as a bridge between UIKit and SwiftUI, allowing developers to embed SwiftUI views within existing UIKit interfaces seamlessly.

UIHostingController inherits from UIViewController and is initialized with a SwiftUI view as its root view. This controller automatically manages the lifecycle of the SwiftUI view, ensuring proper rendering and updates while adhering to UIKit’s view hierarchy. It handles tasks such as view layout, state management, and interaction events, abstracting away much of the complexity involved in combining the two frameworks.

Developers typically use UIHostingController when transitioning an existing UIKit app to SwiftUI incrementally or when embedding SwiftUI components within UIKit-based interfaces. For example, a UIKit app might use a UIHostingController to display a SwiftUI-based settings screen or a custom SwiftUI view within a table view cell.

The class is lightweight and efficient, leveraging SwiftUI’s declarative syntax while conforming to UIKit’s conventions. It supports common UIKit features such as view controllers’ lifecycle methods (e.g., `viewDidLoad`, `viewWillAppear`) and integrates with UIKit’s navigation and presentation stacks. However, it does not provide direct access to UIKit-specific APIs, as it primarily focuses on hosting SwiftUI content.

UIHostingController is particularly useful for developers who need to leverage SwiftUI’s modern UI capabilities while maintaining compatibility with UIKit’s established patterns. Its simplicity and integration with SwiftUI’s declarative model make it a preferred choice for gradual adoption of SwiftUI in UIKit projects.