1page.title=Android 2.2 APIs 2excludeFromSuggestions=true 3sdk.platform.version=2.2 4sdk.platform.apiLevel=8 5sdk.platform.majorMinor=minor 6 7@jd:body 8 9<div id="qv-wrapper"> 10<div id="qv"> 11 12<h2>In this document</h2> 13<ol> 14 <li><a href="#features">Platform Highlights</a></li> 15 <li><a href="#api-level">API Level</a></li> 16 <li><a href="#api">Framework API Changes</a> 17 18 </ol> 19 </li> 20</ol> 21 22<h2>Reference</h2> 23<ol> 24<li><a 25href="{@docRoot}sdk/api_diff/{@sdkPlatformApiLevel}/changes.html">API 26Differences Report »</a> </li> 27</ol> 28 29<h2>See Also</h2> 30<ol> 31 <li><a href="{@docRoot}sdk/exploring.html">Exploring the SDK</a></li> 32</ol> 33 34</div> 35</div> 36 37<p> 38<em>API Level:</em> <strong>{@sdkPlatformApiLevel}</strong></p> 39 40<p>Android {@sdkPlatformVersion} is a {@sdkPlatformMajorMinor} platform release including user 41features, developer features, API changes, and bug 42fixes. For information on developer features and API changes, see the 43<a href="#api">Framework API</a> section.</p> 44 45<p>For developers, the Android {@sdkPlatformVersion} platform is available as a 46downloadable component for the Android SDK. The downloadable platform includes 47an Android library and system image, as well as a set of emulator skins and 48more. To get started developing or testing against Android {@sdkPlatformVersion}, 49use the Android SDK Manager to download the platform into your SDK.</p> 50 51 52<h2 id="features">Platform Highlights</h2> 53 54<p>For a list of new user features and platform highlights, see the <a 55href="http://developer.android.com/about/versions/android-2.2-highlights.html">Android 562.2 Platform Highlights</a> document.</p> 57 58 59<h2 id="api-level">API Level</h2> 60 61<p>The Android {@sdkPlatformVersion} platform delivers an updated version of 62the framework API. The Android {@sdkPlatformVersion} API 63is assigned an integer identifier — 64<strong>{@sdkPlatformApiLevel}</strong> — that is 65stored in the system itself. This identifier, called the "API Level", allows the 66system to correctly determine whether an application is compatible with 67the system, prior to installing the application. </p> 68 69<p>To use APIs introduced in Android {@sdkPlatformVersion} in your 70application, you need to set the proper value, "{@sdkPlatformApiLevel}", in the 71<code>android:minSdkVersion</code> attributes of the <code><uses-sdk></code> 72element in your application's manifest. </p> 73 74<p>For more information about how to use API Level, see the <a 75href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#ApiLevels">API Levels</a> document. </p> 76 77 78<h2 id="api">Framework API Changes</h2> 79 80<p>The sections below provide information about changes made to the application 81framework API provided by the Android {@sdkPlatformVersion} platform.</p> 82 83<h3 id="install-loc">App installation on external storage media</h3> 84 85<p>The Android platform now allows applications to request installation onto the 86device's external storage media (such as the SD card), as an alternative to 87installation onto the device's internal memory. </p> 88 89<p>Application developers can express the preferred installation location for 90their applications by means of a new attribute of <code><manifest></code> 91in the manifest file, <a 92href="{@docRoot}guide/topics/manifest/manifest-element.html#install"><code> 93android:installLocation</code></a>. The attribute supports three values: 94<code>"internalOnly"</code>, <code>"preferExternal"</code>, and 95<code>"auto"</code>. At install time, the system checks the value of 96<code>android:installLocation</code> and installs the application 97<code>.apk</code> according to the preferred location, if possible. If the 98application has requested external installation, the system installs it into a 99private, encrypted partition in the external media. Once an application .apk is 100installed externally, the system lets the user change the storage location of 101the .apk and move it onto the device's internal memory if needed (and vice 102versa), through Manage Applications in the user settings.</p> 103 104<p>By default, the system installs all applications onto the device's internal 105memory, except for those that explicitly request external installation. This 106means that the system will always install legacy applications onto internal 107memory, since they do not have access to the 108<code>android:installLocation</code> attribute. However, it is possible to 109configure and compile a legacy application such that it is installed internally 110on older versions of the platform and externally on Android 2.2 and later 111platforms, if necessary. </p> 112 113<p>Note that requesting installation onto the device's external media is not 114suitable for all applications, particularly because the external media may be 115removable and unmounting/remounting may disrupt the user experience and system 116settings.</p> 117 118<p>For more information about setting a preferred install location for your 119application, including a discussion of what types of applications should and 120should not request external installation, please read the <a 121href="{@docRoot}guide/topics/data/install-location.html">App Install Location</a> 122document. </p> 123 124<h3 id="backup-manager">Data backup</h3> 125 126<p>The platform now provides a generalized backup service that 127applications can use to backup and restore user data, to ensure that users can 128maintain their data when switching devices or reinstalling the application. The 129Backup Manager handles the work of transporting the application data to and from 130the backup storage area in the cloud. The Backup Manager can store any type of 131data, from arbitrary data to files, and manages backup and restore operations 132in an atomic manner. For more information, see <a 133href="{@docRoot}guide/topics/data/backup.html">Data Backup</a>.</p> 134 135<h3>Graphics</h3> 136 137<ul> 138<li>New OpenGL ES 2.0 APIs in {@link android.opengl.GLES20 android.opengl.GLES20}.</li> 139<li>New {@link android.opengl.ETC1}, {@link android.opengl.ETC1Util}, and {@link android.opengl.ETC1Util.ETC1Texture} classes and utility methods for using ETC1 for texture compression.</li> 140<li>New {@link android.graphics.ImageFormat} class.</li> 141<li>New {@link android.graphics.YuvImage YUV image format API} to enable compression from YUV to JPEG and manipulation of YUV data.</li> 142</ul> 143 144<h3>Media</h3> 145 146<ul> 147<li>New APIs in {@link android.media.AudioManager android.media.AudioManager} for managing audio focus, transport control, transient loss of audio focus, ducking.</li> 148<li>New broadcast intent for routing audio to SCO — {@link android.media.AudioManager#ACTION_SCO_AUDIO_STATE_CHANGED} with extras indicating new state.</li> 149<li>New APIs in {@link android.media.SoundPool} to detect completion of sound-loading.</li> 150<li>New APIs in {@link android.media.SoundPool} for auto pause and resume.</li> 151<li>New APIs in {@link android.media.MediaRecorder} for specifying audio settings for number of channels, encoding and sampling rates, sampling rate.</li> 152<li>New APIs for adding files to the media database, so that they are automatically scanned. See {@link android.media.MediaScannerConnection#scanFile(Context, String[], String[], OnScanCompletedListener) MediaScannerConnection.scanFile} and {@link android.media.MediaScannerConnection.OnScanCompletedListener MediaScannerConnection.OnScanCompletedListener}.</li> 153</ul> 154 155<h3>Speech recognition and third-party recognition engines</h3> 156 157<ul> 158<li>The platform provides new speech-recognition APIs that allow applications to have a richer interaction with the available voice recognizer. For example, the APIs are sufficient to integrate voice recognition deeply into an IME.</li> 159<li>The platform also provides a {@link android.speech.RecognitionService} base class that lets third-party developers create plug-in recognition engines. </li> 160<li>New {@link android.speech.RecognitionListener} interface to receive callbacks.</li> 161<li>New {@link android.speech.RecognizerIntent} extras that let a requester app specify details as preferred language, minimum length in milliseconds, and so on.</li> 162</ul> 163 164<h3>Camera and camcorder</h3> 165 166<ul> 167<li>Changes to camera preview API to improve efficieny of preview pipeline. </li> 168<li>New display orientation for camera (it can now work in portrait orientation).</li> 169<li>New APIs in {@link android.hardware.Camera android.hardware.Camera} for managing zoom level.</li> 170<li>New APIs {@link android.hardware.Camera.Parameters android.hardware.Camera.Parameters} for querying and setting device camera settings such as focal length, exposure, zoom level, view angle, and others.</li> 171<li>New {@link android.media.ThumbnailUtils thumbnail} utility for video and image thumbnails.</li> 172<li>New {@link android.media.CamcorderProfile} and {@link android.media.CamcorderProfile} classes enable apps to determine device hardware camera capablities.</li> 173<li>New support in {@link android.media.ExifInterface android.media.ExifInterface} for retrieving GPS and focal length.</li> 174</ul> 175 176<h3>Device policy manager</h3> 177 178<p>New device policy management APIs allow developers to write "device 179administrator" applications that can control security features of the device, 180such as the minimum password strength, data wipe, and so on. Users can select 181the administrators that are enabled on their devices. For more information, see 182the {@link android.app.admin android.app.admin} classees or the example 183application code in <a 184href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/DeviceAdminSample.html">DeviceAdminSample.java</a>.</p> 185 186<h3>UI Framework</h3> 187 188<ul> 189<li>New UI modes "car mode" and "night mode" and {@link android.app.UiModeManager} let applications adjust their application UI for specific user modes. </li> 190<li>New {@link android.view.ScaleGestureDetector} that lets Views detect and handle transformation gestures that involve more than one pointer (multitouch) using the supplied MotionEvents. </li> 191<li>Improvements in the way that multitouch events are reported in {@link android.view.MotionEvent} objects.</li> 192<li>The layout attribute <code>fill_parent</code> is renamed to <code>match_parent</code>. This affects both XML and Java code (see {@link android.view.ViewGroup.LayoutParams}). Note that the platform will continue to honor uses of <code>fill_parent</code> in legacy applications. </li> 193<li>New layout attributes {@link android.R.attr#tabStripEnabled}, {@link android.R.attr#tabStripRight}, and {@link android.R.attr#tabStripLeft} let developers customize the bottom strip of TabWidgets.</li> 194<li>Better support for managed dialogs in Activity.</li> 195</ul> 196 197<h3>Accounts and sync</h3> 198 199<ul> 200<li>New method {@link android.content.ContentResolver#addPeriodicSync(Account, String, Bundle, long) AddPeriodicSync()} lets you schedule a periodic sync with a specific account, authority, and extras at the given frequency.</li> 201</ul> 202 203<h3>New manifest elements and attributes</h3> 204 205<ul> 206<li>For specifying the application's preferred install location (see <a href="#install-loc">App Installation on External Storage Media</a>, above): 207 208<ul> 209 <li>New <code>android:installLocation</code> attribute of the <code><manifest></code> element. Specifies the default install location defined by an application.</li> 210</ul> 211</li> 212 213<li>For managing user data backup (see <a href="#backup-manager">Backup manager</a>, above, for more information): 214 215<ul> 216 <li> New <code>android:backupAgent</code> attribute of the 217<code><application></code> element. Specifies the component name of the 218BackupAgent subclass provided by the application to handle backup/restore 219operations, if any.</li> 220 <li> New <code>android:restoreAnyVersion</code> attribute of the 221<code><application></code> element. Boolean value that indicates whether 222the application is prepared to attempt a restore of any backed-up dataset, even 223if the backup is apparently from a newer version of the application than is 224currently installed on the device.</li> 225</ul> 226</li> 227 228<li>For managing the platform's JIT compiler: 229 230<ul> 231<li>New <code>android:vmSafeMode</code> attribute of the <code><application></code> element. Boolean value that specifies whether to disable JIT compiler optimizations when running the application.</li> 232</ul> 233</li> 234</ul> 235 236<h3>Permissions</h3> 237 238<ul> 239<li><code>android.permission.BIND_DEVICE_ADMIN</code> — Any device administration broadcast receiver must require this permission, to ensure that only the system can interact with it.</li> 240<li><code>android.permission.KILL_BACKGROUND_PROCESSES</code> — Allows an application to call {@link android.app.ActivityManager#killBackgroundProcesses(String)}. 241<li><code>android.permission.BIND_WALLPAPER</code> — Any {@link android.service.wallpaper.WallpaperService} must require this permission, to ensure that only the system can interact with it.</li> 242<li><code>android.permission.SET_TIME</code> — Allows an application to set the system time.</li> 243</ul> 244 245<h3 id="api-diff">API differences report</h3> 246 247<p>For a detailed view of all API changes in Android {@sdkPlatformVersion} (API 248Level {@sdkPlatformApiLevel}), see the <a 249href="{@docRoot}sdk/api_diff/{@sdkPlatformApiLevel}/changes.html">API 250Differences Report</a>.</p> 251 252 253 254