Beginning Android Developments

Tools

To develop Android applications, developers need certain development tools provided by Google. The Android project provides development tools specifically for use with the Eclipse Integrated Development Environment for Java. New developers can download and install Eclipse for free from the Eclipse Foundation website. Developers also need the Android SDK on their development machine to create Android applications. People starting out with Android development can download the Software Development Kit from the official Android website. The Android Development Tools plugin for Eclipse also provides a variety of tools for creating Android applications.

Development Basics

Android applications use a variety of technologies, particularly Java programming and XML markup code. Developers implement program logic using Java classes and objects, with XML resources defining application data and visual elements. Each Android application uses a selection of components from four categories. An 'activity' is a single user interface screen within an application. A 'service' is a background process. A 'content provider' manages data for an application. A 'broadcast receiver' allows applications to detect and respond to system messages.

User Interface

Android user interfaces utilize View and View Group objects. Android applications use Views as the basis for their user interfaces, with widgets creating individual user controls and visible elements such as buttons, text-fields and lists. Developers can also define layouts for the different activities within an Android application. A layout determines the various ways in which user interface objects are arranged relative to one another.

Virtual Devices

When developers compile and run Android applications in Eclipse, they can see how these programs function in various different virtual devices. Using the Android Virtual Device Manager, developers can start up virtual Android handsets such as smartphones and tablet PCs, defining the hardware and software configurations they wish to target. In addition to running and testing applications on virtual devices, developers can deploy their applications on actual devices for testing.

Publishing

To publish an application in the Android Market developers must carry out a few steps. Within Eclipse, exporting a final application package as an APK, or Android Package file, requires only a few clicks. During the exporting process, developers can also sign their applications, which is necessary to publish on the Market. When publishing applications through the Market, correct version numbers must also appear within the Manifest files for applications. Uploading an application to the Market only takes minutes through a developer account.