Fields in the AndroidManifest.xml file

The following listing shows an example for the AndroidManifest.xml file.

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
      package="de.vogella.android.temperature"
      android:versionCode="1"
      android:versionName="1.0">
    <application android:icon="@drawable/icon" android:label="@string/app_name">
        <activity android:name=".Convert"
                  android:label="@string/app_name">
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />
                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>

    </application>
    <uses-sdk android:minSdkVersion="9" />

</manifest> 

The package attribute defines the base package for the Java objects referred to in this file. If a Java object lies within a different package, it must be declared with the full qualified package name.

Google Play requires that every Android application uses its own unique package. Therefore it is a good habit to use your reverse domain name as package name. This will avoid collisions with other Android applications.

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. The Android Market determine based on the versionCode, if it should perform an update of the applications for the existing installations. You typically start with "1" and increase this value by one, if you roll-out a new version of your application.

The <activity> tag defines an activity component. The name attribute points to class, which (if not fully qualified), is relative to the package defined in the package attribute.

The intent filter part in the Android manifest file, tells the Android runtime that this activity should to registered as possible entry point into the application and made available in the launcher of the Android system. The action define that is can be started android:name="android.intent.action.MAIN" ) and the category android:name="android.intent.category.LAUNCHER" category tells the Android system to add the activity to the launcher.

The @string/app_name value refers to resource files which contain the actual value of the application name. The usage of resource file 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 file defines the minimal SDK version for which your application is valid. This will prevent your application being installed on unsupported devices.