Android 1.5 Platform

API Level: 3

Android 1.5 is a major platform release deployable to Android-powered handsets starting in May 2009. The release includes new features for users and developers, as well as changes in the Android framework API.

For developers, the Android 1.5 platform is available as a downloadable component for the Android SDK. The downloadable platform includes a fully compliant Android library and system image, as well as a set of emulator skins, sample applications, and more. The downloadable platform is fully compliant and includes no external libraries.

To get started developing or testing against the Android 1.5 platform, use the Android SDK and AVD Manager tool to download the platform into your Android 1.6 or later SDK. For more information, see Exploring the SDK.

Platform Highlights

For a list of new user features and platform highlights, see the Android 1.5 Platform Highlights document.

Revisions

The sections below provide notes about successive releases of the Android 1.5 platform component for the Android SDK, as denoted by revision number. To determine what revision(s) of the Android 1.5 platforms are installed in your SDK environment, refer to the "Installed Packages" listing in the Android SDK and AVD Manager.

API Level

The Android 1.5 platform delivers an updated version of the framework API. The Android 1.5 API is assigned an integer identifier — 3 — that is stored in the system itself. This identifier, called the "API Level", allows the system to correctly determine whether an application is compatible with the system, prior to installing the application.

To use APIs introduced in Android 1.5 in your application, you need to set the proper value, "3", in the android:minSdkVersion attributes of the <uses-sdk> element in your application's manifest.

For more information about how to use API Level, see the API Levels document.

Framework API Changes

The sections below provide information about the application framework API provided by the Android 1.5 platform.

UI framework

• Framework for easier background/UI thread interaction
• New SlidingDrawer widget
• New HorizontalScrollview widget

AppWidget framework

• APIs for creating secure home screen AppWidgets. For information about how to use AppWidgets, see the Developer's Guide AppWidgets documentation. Also see Introducing home screen widgets and the AppWidget framework on the Android Developer's Blog.
• APIs for populating Live Folders with custom content.

Media framework

• Raw audio recording and playback APIs
• Interactive MIDI playback engine
• Video recording APIs for developers (3GP format)
• Video and photo sharing Intents
• Media search Intent

Input Method framework

• Input Method Service framework
• Text-prediction engine
• Ability to provide downloadable IMEs to users

Application-defined hardware requirements

Applications can now use a new element in their manifest files, <uses-configuration> to indicate to the Android system what hardware features they require in order to function properly. For example, an application might use the element to specify that it requires a physical keyboard or a particular navigation device, such as a trackball. Prior to installing the application, the Android system checks the attributes defined for the <uses-configuration> element and allows the installation to continue only if the required hardware is present.

Speech recognition framework

• Support for using speech recognition libraries via Intent. See RecognizerIntent.

Miscellaneous API additions

• LocationManager - Applications can get location change updates via Intent
• WebView - Touch start/end/move/cancel DOM event support
• Redesigned Sensor Manager APIs
• GLSurfaceView - convenience framework for creating OpenGL applications
• Broadcast Intent for app update install succeeded - for smoother app upgrade experience

API differences report

For a detailed view of API changes in Android 1.5 (API Level 3), as compared to the previous version, see the API Differences Report.

Built-in Applications

The system image included in the downloadable platform provides these built-in applications:

Alarm Clock Browser Calculator Camcorder Camera Contacts Custom Locale (developer app) Dev Tools (developer app)

Dialer Email Gallery IME for Japanese text input Messaging Music Settings Spare Parts (developer app)

Locales

The system image included in the downloadable platform provides a variety of built-in locales. In some cases, region-specific strings are available for the locales. In other cases, a default version of the language is used. The languages that are available in the Android 1.5 system image are listed below (with language_country/region locale descriptor).

Chinese, PRC (zh_CN) Chinese, Taiwan (zh_TW) Czech (cs_CZ) Dutch, Netherlands (nl_NL) Dutch, Belgium (nl_BE) English, US (en_US) English, Britain (en_GB) English, Canada (en_CA) English, Australia (en_AU) English, New Zealand (en_NZ) English, Singapore(en_SG) French, France (fr_FR) French, Belgium (fr_BE)

French, Canada (fr_CA) French, Switzerland (fr_CH) German, Germany (de_DE) German, Austria (de_AT) German, Switzerland (de_CH) German, Liechtenstein (de_LI) Italian, Italy (it_IT) Italian, Switzerland (it_CH) Japanese (ja_JP) Korean (ko_KR) Polish (pl_PL) Russian (ru_RU) Spanish (es_ES)

Localized UI strings match the locales that are accessible through Settings.

Emulator Skins

The downloadable platform includes a set of emulator skins that you can use for modeling your application in different screen sizes and resolutions. The emulator skins are:

• QVGA-P (240x320, low density, small screen)
• QVGA-L (320x480, low density, small screen)
• HVGA (320x480, medium density, normal screen)
• HVGA-P (320x480, medium density, normal screen)
• HVGA-L (320x480, medium density, normal screen)

For more information about how to develop an application that displays and functions properly on all Android-powered devices, see Supporting Multiple Screens.