[Ios] system framework Learning

IOS system architecture is divided into four layers: Core OS layer, Core Services layer, Media layer, and Cocoa Touch layer ).

Core OS:The underlying layer of the iOS system architecture is the core operating system layer, which includes memory management, file system, power management, and some other operating system tasks. It can directly interact with hardware devices.

Core Services: The second layer is the core service layer. We can use it to access some iOS services.

MediaThe third layer is the media layer. Through this layer, we can use various media files in applications to record audio and video, draw images, and create basic animation effects.

Cocoa Touch: The top layer is the touchable layer, which provides various useful frameworks for our application development, and most of them are related to the user interface, essentially, it is responsible for user touch interaction on iOS devices.

 

InCocoa TouchMany technologies in the layer are based on Objective-C language. Objective-the C language provides iOS with support for collection, file management, and network operations. ImageUIKit frameworkIt provides various visualization components for applications, such as Window, View, and UIButton ). Other frameworks in the Cocoa Touch layer are also very useful for our application development, such as accessing the user's communication recording function framework, obtaining photo information, and accelerating sensors, three-dimensional gyroscope, and other hardware supported frameworks.

For application developers, the most important thing is the Cocoa Touch framework.

 

It is a comparison between Mac OS and iOS system architecture:

As an application developer, although Cocoa Touch and Cocoa are Rarely touched, it is necessary to understand their role. The above IOS system framework and Android have many similarities.

More information:

Http://www.cnblogs.com/zhangmangyuan/archive/2013/03/28/iOS.html

Http://www.kejixun.com/article/201308/17085.html