android demo

http://www.vogella.de/articles/Android/article.html

1.2. Important Android terms
An Android application consists out of the following parts:

Activity - A screen in the Android application

Services - Background activities without UI

Content Provider - provides data to applications, Android contains a SQLLite DB which can serve as data provider

Broadcast Receiver - receives system messages, can be used to react to changed conditions in the system


Intends allow the application to request and / or provide services . For example the application call ask via an intent for a contact application. Application register themself via an IntentFilter. Intends are a powerful concept as they allow to create loosely coupled applications.

An Android application is described the file "AndroidManifest.xml". This files contains all activities application and the required permissions for the application. For example if the application requires network access it must be specified here. "AndroidManifest.xml" can be thought as the deployment descriptor for an Android application.