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This article shows you what the application components are in the foundation of Android, which are concise and easy to understand, which will definitely brighten your eyes. I hope you can get something through the detailed introduction of this article.

Application components are the basic building blocks of an Android application. These components are loosely coupled to the application manifest file AndroidManifest.xml which describes the application of each component and how they interact.

There are four main components that can be used in an Android application:

Component description Activities they determine the user interface and handle user interaction, the smartphone screen Services they handle the background processing related to the application. Broadcast Receivers they handle communication between the Android operating system and applications. Content Providers they deal with data and database management issues. Activities

An activity represents a single on-screen user interface. For example, an email application might have an activity that displays a new email list, another activity, composing emails, reading emails, and other activities. If the application has more than one activity, then one of them should be marked as active when launching the application.

Implemented as a subclass of an active Activity class, as follows:

Public class MainActivity extends Activity {} Services

A service is a component that runs in the background to perform long-running operations. For example, a service can play music in the background while the user is in different applications, or it may obtain data through the network without blocking user interaction and activity.

Implementing a service as a subclass of a service class is as follows:

Public class MyService extends Service {} broadcast receiver

The broadcast receiver simply responds to broadcasting messages from other applications or from the system. For example, an application can also initiate a broadcast to let other applications know that some data has been downloaded to the device for them to use, so this is a broadcast receiver that intercepts this communication and takes appropriate action.

The broadcast receiver is implemented as a subclass of the BroadcastReceiver class, and each message is broadcast as an Intent object.

Public class MyReceiver extends BroadcastReceiver {} content provider

The content provider component provides data from one application to the other. The method of the ContentResolver class, through the handling of such requests. This data can be stored in a file system, in a database, or elsewhere.

Content providers that implement subclasses of the ContentProvider class must implement a standard set of API to enable other applications to perform transactions.

Public class MyContentProvider extends ContentProvider {}

We will cover the details of the application components through these tags, as well as in separate chapters.

Additional component

Add-ons can be used in the above entities, their logic, and the wiring construction between them. These components include:

The component describes the behavior represented by the Fragments or part of the user interface in the activity. Views draws the UI element, list form, etc. of the buttons on the screen. Layouts looks at the hierarchy and controls the screen format and appearance view. The Intents message wiring components are together. Resources external factors, such as strings, constants, and drawable pictures. The configuration file for the Manifest application. What are the application components in the foundation of Android? have you learned any knowledge or skills? If you want to learn more skills or enrich your knowledge reserve, you are welcome to follow the industry information channel.

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