Implement AndroidManifest.xml

An Android application is described the file "AndroidManifest.xml". This file must declare all activities, services, broadcast receivers and content provider of the application. It must also contain 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.

The "package" attribute defines the base package for the following Java elements. It also must be unique as the Android Marketplace only allows application for a specfic package once. Therefore a good habit is to use your reverse domain name as a package to avoid collisions with other developers.

"android:versionName" and "android:versionCode" specify the version of your application. "versionName" is what the user sees and can be any string. "versionCode" must be an integer and the Android Market uses this to determine if you provided a newer version to trigger the update on devices which have your application installed. You typically start with "1" and increase this value by one if you roll-out a new version of your application.

"activity" defines an activity in this example pointing to the class "de.vogella.android.temperature.Convert". For this class an intent filter is registered which defines that this activity is started once the application starts (action android:name="android.intent.action.MAIN"). The category definition (category android:name="android.intent.category.LAUNCHER" ) defines that this application is added to the application directory on the Android device. The @ values refer to resource files which contain the actual values. This makes it easy to provide different resources, e.g. strings, colors, icons, for different devices and makes it easy to translate applications.

The "uses-sdk" part of the "AndroidManifest.xml" defines the minimal SDK version your application is valid for. This will prevent your application being installed on devices with older SDK versions.