Android应用程序的构造块分析(国外英语资料).docVIP

Android应用程序的构造块分析(国外英语资料) Analysis of building blocks for Android applications Android applications are what Android programmers do every day, but its essential for beginners who do not have access to the Android to understand the structure of the application. A Android application is organized mainly from four construction blocks. The four building blocks are: Activity Intent Receiver Service Content Provider Not every Android application has these four building blocks, some of which are not required, and sometimes we just need several of these four to be our application. When we specify what construction blocks our application needs, then we need to register the list of building blocks in AndroidManifest.xml. This is a XML configuration file that defines the components of our application, the capabilities and requirements of the components, and so on. This configuration file is required for each Android application. For AndroidMainfest.xmls Schema, refer to the documentation that comes with the SDK package. Here are some descriptions of the four tectonic blocks: 1, Activity Activity is the most basic of the Android building blocks, and in the application, a activity is usually a separate screen. Each activity is implemented as a separate class and inherits from the base class of Activity. This activity class will show the user interface made up of several Views controls and respond to events. Most applications will contain multiple screens. For example, a short message application will have a screen for displaying contact lists, second screens for writing short messages, and a screen for browsing through old messages and setting up the system. Each of these screens is a activity. Its easy to navigate from one screen to another. In some applications, a screen even returns a value to the previous screen. When a new screen is opened, the previous screen will be paused and saved in the history stack. The user can return to the previous screen in the history stack. Wh