Core service layer of iOS software architecture (Core Services)

We talked about the underlying core OS in the iOS software architecture, and the core service layer of the iOS system, on top of the kernel OS layer, consists of two parts: Core service libraries and advanced features based on core services. This article makes a detailed explanation of these two functions.

First, the core services layer contains the following libraries:

1. Address Book Framework

For Address Book management, developers can manage phone contact lists, access the database of contact lists, and then add, delete, and edit other operations through this library.

2. Cfnetwork Framework

Provides a range of interfaces that enable developers to communicate online more conveniently and quickly. Developers do not have to pay attention to too much detail and can devote more effort to the application.

3. Core Data Framework

Used to manage the data model of an MVC-based model (model, view, Controller) application, which is a relational data management system. Core data provides basic features such as saving, managing, changing, and acquiring data in storage.

4. Core Foundation Framework

It is a C-language library that provides a variety of infrastructure for applications.

5. Core Location Framework

Provides location-based functionality that allows you to use GPS, 3G, and WiFi to detect the location of your users, and the map application can use this feature to display the user's location on the map. Developers can add them to the application to implement related functions, such as providing search services for nearby restaurants, stores, and banks, depending on location.

6. Core Media Framework

Provides relatively low-level media processing, which is rarely used in this library. Readers who need it can watch the clip-Ding Academy iOS online video lectures, which are simple and easy to use.

7. Core Telephony Framework

Provides an interface to help users gather information about the telephony service, for example, users can know which phone provider they are using and know that their device is not on the phone right now.

8. Event Kit Framework

You can let users access calendar events on their devices, use it to get existing calendar events, or add a new event, such as an alarm control.

9. Foundation Framework

The functionality provided is similar to the functionality provided by the core Foundation framework, except that it is a objective-c library.

10. Mobile Core Services Framework

The lower-level data types are defined for UTI (Uniform type Identifiers, uniform type identifier).

11. Quick Look Framework

Allows users to preview the contents of a file.

12. Store Kit Framework

Provides services for communication between the application and the App Store, which allows applications to receive product information from AppStore that users need and display for purchase. When a user needs to purchase a product, the program calls the store kit to collect the purchase information.

13. System Configuration Framework

This library allows users to determine the network configuration of a device, such as whether to use a WiFi connection or whether to connect to a network service.

Ii. advanced features based on core services

1, Blockobjects

C language constructs, which are a very common feature used by iOS developers, can be plugged into C code or objective-c code. Essentially, a block objects is a closed function, or data that accompanies the function. In general, Block objects can be used in several situations:

① instead of proxy and proxy methods.

② instead of a callback function.

③ works asynchronously with the distribution stack.

2. Grand Central Dispatch

Abbreviated as GCD, it adjusts the workload of the application based on the number of processors and only uses the number of threads required for the task to improve the efficiency of the application. For example, when you do not use GCD, if an application needs 20 threads at the maximum load, it will build 20 threads and consume the associated resources even when it is unloaded. When using GCD, the GCD frees up idle resources to speed up the overall system response.

3, Inapp Purchase

Based on the advanced features of the store Kit framework, this feature allows the user to handle the relationship between the account, App Store and application in a good way.

4. Location Services

Based on the core location framework's service capabilities, the application can be positioned for the user to locate the user's current position.

5. SQLite (embedded database)

Allows iOS developers to embed a lightweight SQL database within the application, creating a database file within the application without having to create a separate server, and then managing the list and records.

6. XML Support

Allows developers to parse the XML file in a row.

Recognizing the core service layer of iOS software architecture, the next section we look at the top two layers of the structure of the exclusive functions and areas of responsibility, the top two layers are divided into the media layer and the light touch layer, specifically, we always pay attention to the update of the school information.

Core service layer of iOS software architecture (Core Services)