UIKit is an application development environment and

graphical user interface A graphical user interface, or GUI, is a form of user interface that allows user (computing), users to human–computer interaction, interact with electronic devices through Graphics, graphical icon (computing), icons and visual indicators such ...

toolkit from Apple Inc. used to build apps for the iOS, iPadOS, watchOS, tvOS, and visionOS operating systems. UIKit provides an abstraction layer of iOS, the

operating system An operating system (OS) is system software that manages computer hardware and software resources, and provides common daemon (computing), services for computer programs. Time-sharing operating systems scheduler (computing), schedule tasks for ...

for the iPhone, iPod Touch, and iPad. UIKit is insipired by the AppKit found in the

macOS macOS, previously OS X and originally Mac OS X, is a Unix, Unix-based operating system developed and marketed by Apple Inc., Apple since 2001. It is the current operating system for Apple's Mac (computer), Mac computers. With ...

Cocoa API toolset and, like it, is primarily written in the

Objective-C Objective-C is a high-level general-purpose, object-oriented programming language that adds Smalltalk-style message passing (messaging) to the C programming language. Originally developed by Brad Cox and Tom Love in the early 1980s, it was ...

language. UIKit allows the use of hardware and features that are not found in macOS computers and are thus unique to the iOS range of devices. Just like AppKit, UIKit follows a Model–View–Controller (MVC) software architecture. UIKit contains a different set of graphical control elements from AppKit. Tools for developing applications based on UIKit are included in the iOS SDK.

UIKit in relation to other layers

iOS, watchOS, and tvOS technologies can be seen as a set of layers, with UIKit at the highest level and the core operating system / kernel at the bottom. A hierarchical view of the iOS, watchOS, and tvOS technologies can be shown as follows: # UIKit # Media / Application Services # Core Services # Core OS / iOS kernel

Main features

Some of the main features and technologies of UIKit are: * App Extension * Data Management * Handoff * Document Picker * AirDrop * TextKit * UIKit Dynamics * Multitasking * Auto Layout * Storyboards * UI State Preservation * Apple Push Notification Service * Local Notifications * Gesture Recognisers * Standard System View Controllers

Main frameworks

UIKit provides the key frameworks for developing applications on devices running iOS, and is based atop Foundation Kit. Other frameworks built by Apple that complement AppKit are: * GameKit * MapKit * Address Book UI * EventKit UI * Message UI * Notification Center * PushKit

Ports

Microsoft Microsoft Corporation is an American multinational corporation and technology company, technology conglomerate headquartered in Redmond, Washington. Founded in 1975, the company became influential in the History of personal computers#The ear ...

's WinObjC, the GNUstep-based iOS bridge for the Universal Windows Platform, contains working implementations of frameworks such as Foundation, UIKit, and MapKit released under the

MIT License The MIT License is a permissive software license originating at the Massachusetts Institute of Technology (MIT) in the late 1980s. As a permissive license, it puts very few restrictions on reuse and therefore has high license compatibility. Unl ...

. One of the UIKit implementations is based on XAML. Various efforts have tried to bring UIKit to macOS: * Chameleon is a port of UIKit to

from 2014. * ZeeZide's UXKit is a more recent port of UIKit to macOS. It exists a layer above AppKit and UIKit. * Apple used a "UXKit" private framework for a 2015 version of Photos.app. * Apple made the bridge more official with the "iosMac" or "Marzipan" project in 2018, which put an "iOSSupport" directory full of iOS frameworks in macOS Mojave. They were originally restricted from developer use and was finally made official with the release of Mac Catalyst in 2019.

References

{{iOS Gesture recognition IOS IPhone Proprietary software