about/versions/android-3.2.jd

page.title=Android 3.2 Platform
sdk.platform.version=3.2
sdk.platform.apiLevel=13
@jd:body

<div id="qv-wrapper">
<div id="qv">

<h2>In this document</h2>
<ol>
  <li><a href="#highlights">Highlights</a></li>
  <li><a href="#api">API Overview</a></li>
  <li><a href="#api-level">API Level</a></li>
</ol>

<h2>Reference</h2>
<ol>
<li><a
href="{@docRoot}sdk/api_diff/13/changes.html">API
Differences Report &raquo;</a> </li>
</ol>

</div>
</div>


<p><em>API Level:</em>&nbsp;<strong>{@sdkPlatformApiLevel}</strong></p>

<p>Android 3.2 is an incremental platform release that adds new
capabilities for users and developers. The sections below provide an overview
of the new features and developer APIs.</p>

<p>For developers, the Android {@sdkPlatformVersion} platform is available as a
downloadable component for the Android SDK. The downloadable platform includes
an Android library and system image, as well as a set of emulator skins and
more. To get started developing or testing against Android {@sdkPlatformVersion},
use the Android SDK Manager to download the platform into your SDK.</p>


<h2 id="highlights" style="margin-top:1.5em;">Platform Highlights</h2>

<h3>New user features</h3>

<ul>
<li><strong>Optimizations for a wider range of tablets</strong>

<p>Android 3.2 includes a variety of optimizations across the system
to ensure a great user experience on a wider range of tablet devices.</p></li>

<li><strong>Compatibility zoom for fixed-sized apps</strong>

<p>Android 3.2 introduces a new <em>compatibility zoom</em> mode that gives
users a new way to view fixed-sized apps on larger devices. The new mode provides a
pixel-scaled alternative to the standard UI stretching for apps that are not
designed to run on larger screen sizes, such as on tablets. The new mode is
accessible to users from a menu icon in the system bar, for apps that need
compatibility support.</p></li>

<li><strong>Media sync from SD card</strong>
<p>On devices that support an SD card, users can now load media files directly
from the SD card to apps that use them. A system facility makes the files
accessible to apps from the system media store.</p></li>
</ul>


<h3>New developer features</h3>

<ul>
<li><strong>Extended API for managing screens support</strong>

<p>Android 3.2 introduces extensions to the platform's screen support API to
give developers additional ways to manage application UI across the range of
Android-powered devices. The API includes new resource qualifiers and new
manifest attributes that give you more precise control over how your
apps are displayed on different sizes, rather than relying on generalized
size categories.</p>

<p>To ensure the best possible display for fixed-sized apps and apps with limited
support for various screen sizes, the platform also provides a new zoom
compatibility mode that renders the UI on a smaller screen area, then scales it
up to fill the space available on the display. For more information about the
screen support API and the controls it provides, see the sections below. </p></li>
</ul>


<h2 id="api">API Overview</h2>

<h3 id="usb">Screens Support APIs</h3>

<p>Android 3.2 introduces new screens support APIs that give you more
control over how their applications are displayed across different screen sizes.
The API builds on the existing screens-support API, including the platform's
generalized screen density model, but extends it with the ability to precisely
target specific screen ranges by their dimensions, measured in
density-independent pixel units (such as 600dp or 720dp wide), rather than
by their generalized screen sizes (such as large or xlarge)</p>

<p>When designing an application's UI, you can still rely on the platform to
provide density abstraction, which means that applications do not need to
compensate for the differences in actual pixel density across devices. You
can design the application UI according to the amount of horizontal or vertical
space available. The platform expresses the amount of space available using three new
characteristics: <em>smallestWidth</em>, <em>width</em>, and
<em>height</em>.</p>

<ul>
<li>A screen's <em>smallestWidth</em> is its fundamental minimum size,
measured in density-independent pixel ("dp") units. Of the screen's height or
width, it is the shorter of the two. For a screen in portrait orientation, the
smallestWidth is normally based on its width, while in landscape orientation it is based
on its height. In all cases, the smallestWidth is derived from a fixed characteristic of the
screen and the value does not change, regardless of orientation. The smallestWidth
is important for applications because it represents the shortest possible width
in which the application UI will need to be drawn, not including screen areas
reserved by the system.
</li>

<li>In contrast, a screen's <em>width</em> and <em>height</em> represent the
current horizontal or vertical space available for application layout, measured
in "dp" units, not including screen areas reserved by the system. The width and
height of a screen change when the user switches orientation between landscape
and portrait. </li>

</ul>

<p>The new screens support API is designed to let you manage application UI
according to the smallestWidth of the current screen. You can also manage the
UI according to current width or height, as needed. For those purposes, the API
provides these tools:</p>

<ul>
<li>New resource qualifiers for targeting layouts and other resources to a
minimum smallestWidth, width, or height, and</li>
<li>New manifest attributes, for specifying the app's maximum
screen compatibility range</li>
</ul>

<p>Additionally, applications can still query the system and manage UI and
resource loading at runtime, as in the previous versions of the platform.</p>

<p>Since the new API lets you target screens more directly through smallestWidth,
width, and height, it's helpful to understand the typical
characteristics of the different screen types. The table below provides some
examples, measured in "dp" units. </p>

<p class="caption"><strong>Table 1.</strong> Typical devices, with density
and size in dp.</p>

<table>
<tr>
<th>Type</th>
<th>Density (generalized)</th>
<th>Dimensions (dp)</th>
<th>smallestWidth (dp)</th>
</tr>
<tr>
<td>Baseline phone</td>
<td>mdpi</td>
<td>320x480</td>
<td>320</td>
</td>
<tr>
<td>Small tablet/large phone</td>
<td>mdpi</td>
<td>480x800</td>
<td>480</td>
</tr>
<tr>
<td>7-inch tablet</td>
<td>mdpi</td>
<td>600x1024</td>
<td>600</td>
</tr>
<tr>
<td>10-inch tablet</td>
<td>mdpi</td>
<td>800x1280</td>
<td>800</td>
</tr>
</table>

<p>The sections below provide more information about the new screen qualifiers
and manifest attributes. For complete information about how to use the screen
support API, see <a
href="{@docRoot}guide/practices/screens_support.html">Supporting Multiple
Screens</a>.</p>

<h4>New resource qualifiers for screens support</h4>

<p>The new resource qualifiers in Android 3.2 let you better target your layouts
for ranges of screen sizes. Using the qualifiers, you can create resource
configurations designed for a specific minimum smallestWidth, current width, or
current height, measured in density-independent pixels.</p>

<p>The new qualifiers are:</p>
<ul>
<li><code>swNNNdp</code> &mdash; Specifies the minimum smallestWidth on which
the resource should be used, measured in "dp" units. As mentioned above, a
screen's smallestWidth is constant, regardless of orientation. Examples:
<code>sw320dp</code>, <code>sw720dp</code>, <code>sw720dp</code>.</li>

<li><code>wNNNdp</code> and <code>hNNNdp</code> &mdash; Specifies the minimum
width or height on which the resource should be used, measured in "dp" units. As
mentioned above, a screen's width and height are relative to the orientation of
the screen and change whenever the orientation changes. Examples:
<code>w320dp</code>, <code>w720dp</code>, <code>h1024dp</code>.</p></li>
</ul>

<p>You can also create multiple overlapping resource configurations if needed.
For example, you could tag some resources for use on any screen wider than 480
dp, others for wider than 600  dp, and others for wider than 720 dp. When
multiple resource configurations are qualified for a given screen, the system
selects the configuration that is the closest match. For precise control over
which resources are loaded on a given screen, you can tag resources with one
qualifier or combine several new or existing qualifiers.

<p>Based on the typical dimensions listed earlier, here are some examples of how
you could use the new qualifiers:</p>

<pre class="classic prettyprint">res/layout/main_activity.xml   # For phones
res/layout-sw600dp/main_activity.xml   # For 7 tablets
res/layout-sw720dp/main_activity.xml   # For 10 tablets
res/layout-w600dp/main_activity.xml   # Multi-pane when enough width
res/layout-sw600dp-w720dp/main_activity.xml   # For large width</pre>

<p>Older versions of the platform will ignore the new qualifiers, so you can
mix them as needed to ensure that your app looks great on any device. Here
are some examples:</p>

<pre class="classic prettyprint">res/layout/main_activity.xml   # For phones
res/layout-xlarge/main_activity.xml   # For pre-3.2 tablets
res/layout-sw600dp/main_activity.xml   # For 3.2 and up tablets</pre>

<p>For complete information about how to use the new qualifiers, see <a href="{@docRoot}guide/practices/screens_support.html#NewQualifiers">Using new
size qualifiers</a>.</p>

<h4>New manifest attributes for screen-size compatibility</h4>

<p>The framework offers a new set of <a
href="{@docRoot}guide/topics/manifest/supports-screens-element.html"><code>&lt;supports-screens&gt;</code></a> manifest attributes that let
you manage your app's support for different screen sizess.
Specifically, you can specify the largest and smallest screens on which your app
is designed to run, as well as the largest screen on which it is designed run
without needing the system's new <a href="{@docRoot}guide/practices/screen-compat-mode.html">screen
compatibility mode</a>. Like the resource qualifiers described above, the new
manifest attributes specify the range of screens that the application supports,
as specified by the smallestWidth. </p>

<p>The new manifest attributes for screen support are: </p>

<ul>
<li><code>android:compatibleWidthLimitDp="<em>numDp"</em></code> &mdash; This
attribute lets you specify the maximum smallestWidth on which the application
can run without needing compatibility mode. If the current screen is larger than
the value specified, the system displays the application in normal mode but
allows the user to optionally switch to compatibility mode through a setting in
the system bar.</li>

<li><code>android:largestWidthLimitDp="<em>numDp</em>"</code> &mdash; This
attribute lets you specify the maximum smallestWidth on which the application
is designed to run.  If the current screen is larger than the value specified,
the system forces the application into screen compatibility mode, to ensure best
display on the current screen.</li>

<li><code>android:requiresSmallestWidthDp="<em>numDp"</em></code> &mdash; This
attribute lets you specify the minimum smallestWidth on which the application
can run. If the current screen is smaller than the value specified, the system
considers the application incompatible with the device, but does not prevent it
from being installed and run.</li>
</ul>

<p class="note"><strong>Note:</strong> Google Play does not currently filter
apps based on any of the attributes above. Support for filtering will be
added in a later platform release. Applications that require
filtering based on screen size can use the existing <code>&lt;supports-screens&gt;</code>
attributes.</p>

<p>For complete information about how to use the new attributes, see <a href="{@docRoot}guide/practices/screens_support.html#DeclaringScreenSizeSupport">Declaring
screen size support</a>.</p>

<h4>Screen compatibility mode</h4>

<p>Android 3.2 provides a new screen compatibility mode for applications
explicitly declaring that they do not support screens as large as the one on
which they are running. This new "zoom" mode is a pixel-scaled &mdash; it
renders the application in a smaller screen area and then scales the pixels to
fill the current screen.</p>

<p>By default, the system offers screen compatibility mode as an user option, for apps
that require it. Users can turn the zoom mode on and off using a control available
in the system bar. </p>

<p>Because the new screen compatibility mode may not be appropriate for all
applications, the platform allows the application to disable it using manifest
attributes. When disabled by the app, the system does not offer "zoom" compatibility
mode as an option for users when the app is running.</p>

<p class="note"><strong>Note:</strong> For important information about how
to control compatibility mode in your applications, please review the <a
href="http://android-developers.blogspot.com/2011/07/new-mode-for-apps-on-large-
screens.html">New Mode for Apps on Large Screens</a> article on the Android
Developers Blog. </p>

<h4>New screen density for 720p televisions and similar devices</h4>

<p>To meet the needs of applications running on 720p televisions or similar with
moderate density screens, Android 3.2 introduces a new generalized density,
<code>tvdpi</code>, with an approximate dpi of 213. Applications can query for
the new density in {@link android.util.DisplayMetrics#densityDpi} and can use
the new <code>tvdpi</code> qualifier to tag resources for televisions and
similar devices. For example:</p>

<pre class="classic prettyprint">res/drawable-tvdpi/my_icon.png   # Bitmap for tv density</pre>

<p>In general, applications should not need to work with this density. For situations
where output is needed for a 720p screen, the UI elements can be scaled
automatically by the platform.</p>


<h3 id="ui" style="margin-top:1.25em;">UI framework</h3>
<ul>
<li>Fragments
  <ul>
    <li>New {@link android.app.Fragment.SavedState} class holds the state
    information retrieved from a fragment instance through
    {@link android.app.FragmentManager#saveFragmentInstanceState(android.app.Fragment) saveFragmentInstanceState()}.</li>
    <li>New method {@link android.app.FragmentManager#saveFragmentInstanceState(android.app.Fragment) saveFragmentInstanceState()}
    saves the current instance state of
    the given Fragment. The state can be used later when creating a new instance
    of the Fragment that matches the current state.</li>
    <li>New method {@link android.app.Fragment#setInitialSavedState(SavedState) setInitialSavedState()}
    sets the initial saved state for a Fragment when first constructed.</li>
    <li>New {@link android.app.Fragment#onViewCreated(android.view.View, android.os.Bundle)
    onViewCreated()} callback method notifies the Fragment that
    {@link android.app.Fragment#onCreateView(LayoutInflater, ViewGroup, Bundle) onCreateView()}
    has returned, but before any saved state has been restored in to the View.</li>
    <li>{@link android.app.Fragment#isDetached()} method determines whether
    the Fragment has been explicitly detached from the UI.</li>
    <li>New {@link android.app.FragmentTransaction#attach(android.app.Fragment) attach()}
    and {@link android.app.FragmentTransaction#detach(android.app.Fragment) detach()}
    methods let an application re-attach or detach fragments in the UI.</li>
    <li>A new {@link android.app.FragmentTransaction#setCustomAnimations(int, int, int, int)
    setCustomAnimations()} overload method lets you set specific animation
    resources to run for enter/exit operations and specifically when
    popping the back stack. The existing implementation does not account
    for the different behavior of fragments when popping the back stack.</li>
  </ul>
</li>
<li>Screen size information in ActivityInfo and ApplicationInfo
  <ul>
    <li>{@link android.content.pm.ActivityInfo} adds {@link android.content.pm.ActivityInfo#CONFIG_SCREEN_SIZE}
    and {@link android.content.pm.ActivityInfo#CONFIG_SMALLEST_SCREEN_SIZE} as bit masks
    in {@link android.R.attr#configChanges}. The bits indicate whether an Activity can
    itself handle the screen size and smallest screen size.</li>
    <li>{@link android.content.pm.ApplicationInfo} adds
    {@link android.content.pm.ApplicationInfo#largestWidthLimitDp}, {@link android.content.pm.ApplicationInfo#compatibleWidthLimitDp},
    and {@link android.content.pm.ApplicationInfo#requiresSmallestWidthDp} fields,
    derived from the corresponding <code>&lt;supports-screens&gt;</code> attributes
    in the application manifest file.</li>
  </ul>
</li>
<li>Helpers for getting display size from WindowManager
  <ul>
    <li>New methods {@link android.view.Display#getSize(android.graphics.Point)
    getSize()} and {@link android.view.Display#getRectSize(android.graphics.Rect)
    getRectSize()} let applications get the raw size of the display.</li>
  </ul>
</li>
<li>New public "holographic" styles
  <ul>
    <li>The platform now exposes a variety of public "holographic" styles
    for text, actionbar widgets and tabs, and more. See
    {@link android.R.style} for a full list.</li>
  </ul>
</li>
<li>{@link android.app.LocalActivityManager}, {@link android.app.ActivityGroup}, and
    {@link android.app.LocalActivityManager} are now deprecated
  <ul>
    <li>New applications should use Fragments instead of these classes. To
    continue to run on older versions of the platform, you can use the v4 Support
    Library (compatibility library), available in the Android SDK. The v4 Support
    Library provides a version of the Fragment API that is compatible down to
    Android 1.6 (API level 4).
    <li>For apps developing against Android 3.0 (API level
    11) or higher, tabs are typically presented in the UI using the new
    {@link android.app.ActionBar#newTab() ActionBar.newTab()} and related APIs
    for placing tabs within their action bar area.</p></li>
  </ul>
</li>
</ul>

<h3 id="media" style="margin-top:1em;">Media framework</h3>
<ul>
    <li>Applications that use the platform's media provider ({@link
    android.provider.MediaStore}) can now read media data directly from the
    removeable SD card, where supported by the device. Applications can also
    interact with the SD card files directly, using the MTP API. </li>

</ul>
<h3 id="graphics" style="margin-top:1.25em;">Graphics</h3>
<ul>
<li>Parcelable utilities in Point and PointF
  <ul>
    <li>{@link android.graphics.Point} and {@link android.graphics.PointF}
    classes now include the {@link android.os.Parcelable} interface and utility methods {@link
    android.graphics.Point#describeContents()}, {@link
    android.graphics.Point#readFromParcel(android.os.Parcel) readFromParcel()}, and {@link
    android.graphics.Point#writeToParcel(android.os.Parcel, int) writeToParcel()}.</li>
  </ul>
</li>
</ul>


<h3 id="ime" style="margin-top:1.25em;">IME framework</h3>
<ul>
    <li>New {@link android.view.KeyEvent#getModifiers()} method for
    retrieving the current state of the modifier keys.</li>
</ul>


<h3 id="usb" style="margin-top:1.25em;">USB framework</h3>
<ul>
    <li>New {@link
    android.hardware.usb.UsbDeviceConnection#getRawDescriptors()} method for
    retrieving the raw USB descriptors for the device. You can use the
    method to access descriptors not supported directly via the higher
    level APIs.</li>
</ul>


<h3 id="network" style="margin-top:1.25em;">Network</h3>
<ul>
<li>Network type constants
   <ul>
     <li>{@link android.net.ConnectivityManager} adds the constants {@link
     android.net.ConnectivityManager#TYPE_ETHERNET} and {@link
     android.net.ConnectivityManager#TYPE_BLUETOOTH}.</li>
  </ul>
</li>
</ul>


<h3 id="telephony" style="margin-top:1.25em;">Telephony</h3>
<ul>
    <li>New {@link android.telephony.TelephonyManager#NETWORK_TYPE_HSPAP} network type constant.</li>
</ul>

<h3 id="other" style="margin-top:1.25em;">Core utilities</h3>
<ul>
<li>Parcelable utilities
  <ul>
    <li>New interface {@link android.os.Parcelable.ClassLoaderCreator} allows
    the application to receive the ClassLoader in which the object is being created.</li>
    <li>New {@link android.os.ParcelFileDescriptor#adoptFd(int) adoptFd}, {@link
    android.os.ParcelFileDescriptor#dup(java.io.FileDescriptor) dup()}, and {@link
    android.os.ParcelFileDescriptor#fromFd(int) fromFd()} for managing
    {@link android.os.ParcelFileDescriptor} objects.</li>
  </ul>
</li>
<li>Binder and IBinder
  <ul>
    <li>New method {@link android.os.Binder#dumpAsync(java.io.FileDescriptor, java.lang.String[]) dumpAsync()}
    in {@link android.os.Binder} and {@link android.os.IBinder} let applications
    dump to a specified file, ensuring that the target executes asynchronously.</li>
    <li>New {@link android.os.IBinder} protocol transaction code {@link
    android.os.IBinder#TWEET_TRANSACTION} lets applications send a tweet
    to the target object.</li>
  </ul>
</li>
</ul>


<h3 id="features">New feature constants</h3>

<p>The platform adds new hardware feature constants that you can declare
in their application manifests, to inform external entities such as Google
Play of required hardware and software capabilities. You declare these
and other feature constants in <a
href="{@docRoot}guide/topics/manifest/uses-feature-element.html">{@code
&lt;uses-feature&gt;}</a> manifest elements.

<p>Google Play filters applications based on their <code>&lt;uses-feature&gt;</code> attributes, to ensure that they are available only to devices on which their requirements are met. </p>

<ul>
<li>Feature constants for landscape or portrait requirements

<p>Android 3.2 introduces new feature constants that let applications specify whether they require display in landscape orientation, portrait orientation, or both. Declaring these constants indicates that the application must not be installed on a device that doesn't offer the associated orientation. Conversely, if one or both of the constants are not declared, it indicates that the application does not have a preference for the undeclared orientations and may be installed on a device that doesn't offer them. </p>

<ul>
  <li>{@link android.content.pm.PackageManager#FEATURE_SCREEN_LANDSCAPE
android.hardware.screen.landscape} &mdash; The application requires display in
landscape orientation.</li>
  <li>{@link android.content.pm.PackageManager#FEATURE_SCREEN_PORTRAIT
android.hardware.screen.portrait} &mdash; The application requires display in
portrait orientation.</li>
</ul>

<p>A typical application that functions properly in both landscape and portrait orientations would not normally need to declare an orientation requirement. Rather, an application designed primarily for one orientation, such as an app designed for a television, could declare one of the constants to ensure that it isn't available to devices that don't provide that orientation.</p>

<p>If any of activities declared in the manifest request that they run in a specific orientation,
using the <a href="{@docRoot}guide/topics/manifest/activity-element.html#screen">{@code
android:screenOrientation}</a> attribute, then this also declares that the application
requires that orientation.</p>

</li>
<li>Other feature constants

<ul>
  <li>{@link android.content.pm.PackageManager#FEATURE_FAKETOUCH_MULTITOUCH_DISTINCT
android.hardware.faketouch.multitouch.distinct} &mdash; The application requires support for emulated mulitouch input with distinct tracking of two or more points.</li>

  <li>{@link android.content.pm.PackageManager#FEATURE_FAKETOUCH_MULTITOUCH_JAZZHAND
android.hardware.faketouch.multitouch.jazzhand} &mdash; The application requires support for emulated mulitouch input with distinct tracking of five or more points.</li>
</ul>

</li>
</ul>


<h3 id="api-diff">API Differences Report</h3>

<p>For a detailed view of all API changes in Android {@sdkPlatformVersion} (API
Level
{@sdkPlatformApiLevel}), see the <a
href="{@docRoot}sdk/api_diff/{@sdkPlatformApiLevel}/changes.html">API
Differences Report</a>.</p>


<h2 id="api-level">API Level</h2>

<p>The Android {@sdkPlatformVersion} platform delivers an updated version of
the framework API. The Android {@sdkPlatformVersion} API
is assigned an integer identifier &mdash;
<strong>{@sdkPlatformApiLevel}</strong> &mdash; 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. </p>

<p>To use APIs introduced in Android {@sdkPlatformVersion} in your application,
you need compile the application against the Android library that is provided in
the Android {@sdkPlatformVersion} SDK platform. Depending on your needs, you
might
also need to add an <code>android:minSdkVersion="{@sdkPlatformApiLevel}"</code>
attribute to the <code>&lt;uses-sdk&gt;</code> element in the application's
manifest.</p>

<p>For more information, read <a href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#ApiLevels">What is API
Level?</a></p>