--- /dev/null
+page.title=Optimizing Apps for Android 3.0
+@jd:body
+
+<div id="qv-wrapper">
+<div id="qv">
+<h2>In this document</h2>
+<ol>
+<li><a href="#Setup">Set Up Your SDK with Android 3.0</a></li>
+<li><a href="#SearchableConfiguration">Optimize Your App for Tablets and Similar Devices</a></li>
+<li><a href="#SearchableActivity">Upgrade or Develop a New App for Tablets and Similar
+Devices</a></li>
+</ol>
+
+</div>
+</div>
+
+<p>If you're developing an Android application, Android 3.0 introduces several features that allow
+you to enhance your user's experience on tablets and similar devices. Any application you've already
+published is compatible with devices running Android 3.0, by default, because Android applications
+are forward-compatible. However, there are some simple changes you should make to optimize your
+application for tablet-type devices.</p>
+
+<p>This document shows how you can optimize your existing application for Android 3.0 and
+maintain compatibility with older versions or upgrade your application completely with new APIs.</p>
+
+
+<p><b>To get started:</b></p>
+
+<ol>
+ <li><a href="#Setup">Set up your SDK with Android 3.0</a>.</li>
+ <li>Then choose to either optimize or upgrade:
+ <ol type="a">
+ <li><a href="#Optimize">Optimize Your App for Tablets and Similar Devices</a>.
+ <p>When you have an existing application and want to maintain compatibility with
+older versions of Android.</p>
+ </li>
+ <li><a href="#Upgrade">Upgrade or Develop a New App for Tablets and Similar Devices</a>.
+ <p>When you want to upgrade your application to use APIs introduced in Android 3.0 or
+ create a new application targeted to tablets and similar devices.</p></li>
+ </ol>
+ </li>
+</ol>
+
+
+<h2 id="Setup">Set Up Your SDK with Android 3.0</h2>
+
+<p>To start testing and developing your application on Android 3.0, set up your existing Android
+SDK with the new platform:</p>
+
+<p>(If you don't have an existing Android SDK, <a href="{@docRoot}sdk/index.html">download the
+SDK starter package now</a>.)</p>
+
+<ol>
+ <li><a href="{@docRoot}sdk/adding-components.html#launching">Launch the Android SDK and AVD
+Manager</a> and install the following:
+ <ul>
+ <li>SDK Platform Android 3.0</li>
+ <li>Android SDK Tools, revision 10</li>
+ <li>Android SDK Platform-tools, revision 3</li>
+ <li>Documentation for Android SDK, API 11</li>
+ <li>Samples for SDK API 11</li>
+ </ul>
+ </li>
+ <li><a href="{@docRoot}guide/developing/other-ide.html#AVD">Create an AVD</a> for a tablet-type
+device:
+ <p>Set the target to "Android 3.0" and the skin to "WXGA" (the default skin).</p></li>
+</ol>
+
+
+<h3>About emulator performance</h3>
+
+<p>Because the Android emulator must simulate the ARM instruction set on your computer
+and the WXGA screen is significantly larger than a typical virtual device, emulator performance is
+much slower than a real device.</p>
+
+<p>In particular, initializing the emulator can be slow and can take several minutes, depending on
+your hardware. When the emulator is booting, there is limited user feedback, so please be patient
+and wait until you see the home screen (or lock screen) appear. </p>
+
+<p>However, you don't need to boot the emulator each time you rebuild your
+application—typically you only need to boot at the start of a session and keep it running.
+Also see the tip below for information about using a snapshot to drastically reduce startup time
+after the first initialization. </p>
+
+<p>We're working hard to resolve the performance issues and it will improve in future tools
+releases. For the time being, the emulator is still best way to evaluate your application's
+appearance and functionality on Android 3.0 without a real device.</p>
+
+<p class="note"><strong>Tip:</strong> To improve the startup time for the emulator, enable snapshots
+for the AVD when you create it with the SDK and AVD Manager (there's a checkbox in the AVD creator
+to <strong>Enable</strong> snapshots). Then, start the AVD from the AVD manager and check <b>Launch
+from snapshot</b> and <b>Save to snapshot</b>. This way, when you close the emulator, a snapshot of
+the AVD state is saved and used to quickly relaunch the AVD next time. However, when you choose to
+save a snapshot, the emulator will be slow to close, so you might want to disable <b>Save to
+snapshot</b> after you've acquired an initial snapshot (after you close the AVD for the first
+time).</p>
+
+
+
+<h2 id="Optimize">Optimize Your Application for Tablets and Similar Devices</h2>
+
+<p>If you've already developed an application for an earlier version of Android, there are a few
+things you can do to optimize it for a tablet-style experience on Android 3.0 without changing the
+minimum version required (you don't need to change your manifest's <a
+href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#min">{@code
+android:minSdkVersion}</a>).</p>
+
+<p class="note"><strong>Note:</strong> All Android applications are forward-compatible, so
+there's nothing you <em>have to</em> do—if your application is a good citizen of the Android
+APIs, your app should work fine on devices running Android 3.0. However, in order to provide users
+a better experience when using your app on an Android 3.0 tablet or similar-size device, you
+should update your application to inherit the new system theme and provide some optimizations for
+larger screens.</p>
+
+<p>Here are a few things you can do to optimize your application for devices running Android
+3.0:</p>
+
+<ol>
+ <li><b>Test your current application on Android 3.0</b>
+ <ol>
+ <li>Build your application as-is and install it on your Android 3.0 AVD (created above during
+<a href="#Setup">setup</a>).</li>
+ <li>Perform your usual tests to be sure everything works and looks as expected.</li>
+ </ol>
+ </li>
+
+ <li><b>Apply the new "holographic" theme to your application</b>
+ <ol>
+ <li>Open your manifest file and update the <a
+href="{@docRoot}guide/topics/manifest/uses-sdk-element.html">{@code <uses-sdk>}</a> element to
+set <a
+href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#target">{@code
+android:targetSdkVersion}</a> to {@code "11"}. For example:
+<pre>
+<manifest ... >
+ <uses-sdk android:minSdkVersion="4"
+ android:targetSdkVersion="11" />
+ <application ... >
+ ...
+ <application>
+</manifest>
+</pre>
+ <p>By targeting the Android 3.0 platform, the system automatically applies the holographic theme
+to each activity when your application runs on an Android 3.0 device. The holographic theme
+provides a new design for widgets, such as buttons and text boxes, and restyles other
+visual elements. This is the standard theme in applications built for Android 3.0, so your
+application will look more at home by enabling the theme.</p>
+ <p>Additionally, the holographic theme enables the <a
+href="{@docRoot}guide/topics/ui/actionbar.html">Action Bar</a> in your activities when running on an
+Android 3.0 device. The Action Bar replaces the traditional title bar at the top of the activity
+window and provides the user access to the activity's Options Menu.</p>
+ </li>
+ <li>Continue to build your application against the minimum version specified by <a
+href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#min">{@code android:minSdkVersion}</a>,
+but install it on the Android 3.0 AVD. Repeat your tests to be sure that your user interface works
+well with the holographic theme.
+ <p class="note"><strong>Note:</strong> If you have applied other themes directly to your
+activities, they will override the inherited holographic theme. To resolve this, you can use
+the <a href="{@docRoot}guide/topics/resources/providing-resources.html#VersionQualifier">system
+version qualifier</a> to provide an alternative theme for Android 3.0 devices that's based on the
+holographic theme. For more information, read how to <a
+href="{@docRoot}guide/topics/ui/themes.html#SelectATheme">select a theme based on platform
+version</a>.</p>
+ </ol>
+ </li>
+
+ <li><b>Supply alternative layout resources for xlarge screens</b>
+ <p>By providing <a
+href="{@docRoot}guide/topics/resources/providing-resources.html#AlternativeResources">alternative
+resources</a> when running on extra large screens (using the <code>xlarge</code> resource
+qualifier), you can improve the user experience of your application on tablet-type devices without
+using new APIs.</p>
+ <p>For example, here are some things to consider when creating a new layout for extra large
+screens:</p>
+ <ul>
+ <li>Landscape layout: The "normal" orientation for tablet-type devices is usually landscape
+(wide), so you should be sure that your activities offer a layout that's optimized for a wide
+viewing area. <p>You can specify landscape resources with the <code>land</code> resource
+qualifier, but if you want alternative resources for an extra large landscape screen, you
+should use both <code>xlarge</code> and <code>land</code> qualifiers. For example, {@code
+res/layout-xlarge-land/}. The order of the qualifier names is important; see <a
+href="{@docRoot}guide/topics/resources/providing-resources.html#AlternativeResources">
+Providing Alternative Resources</a> for more information.</p></li>
+ <li>Button position: Consider whether the position of the most common buttons in your UI are
+easily accessible while holding a tablet with two hands.</li>
+ <li>Font sizes: Be sure your application uses {@code sp} units when setting font
+sizes. This alone should ensure a readable experience on tablet-style devices. In some cases,
+however, you might want to consider larger font sizes for <code>xlarge</code> configurations.</li>
+ </ul>
+ <p>In general, always be sure that your application follows the <a
+href="{@docRoot}guide/practices/screens_support.html#screen-independence">Best Practices
+for Screen Independence</a>.</p>
+ </li>
+</ol>
+
+
+
+
+
+<h2 id="Upgrade">Upgrade or Develop a New App for Tablets and Similar Devices</h2>
+
+<p>If you want to develop an application that's fully enhanced for tablet-type devices running
+Android 3.0, then you need to use new APIs in Android 3.0. This section introduces some of
+the new features you should use.</p>
+
+
+<h3>Declare the minimum system version</h3>
+
+<p>The first thing to do when you create a project for Android 3.0 is set your manifest's <a
+href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#min">{@code android:minSdkVersion}</a>
+to {@code "11"}. For example:</p>
+
+<pre>
+<manifest ... >
+ <uses-sdk android:minSdkVersion="11" />
+ <application ... >
+ ...
+ <application>
+</manifest>
+</pre>
+
+<p>By targeting the Android 3.0 platform, the system automatically applies the new holographic theme
+to each of your activities.</p>
+
+<p>Additionally, the holographic theme enables the Action Bar for each activity.</p>
+
+
+<h3>Use the Action Bar</h3>
+
+<p>The Action Bar is a widget for activities that replaces the traditional title bar at the top of
+the screen. By default, the Action Bar includes the application logo on the left side, followed by
+the activity title, and any available items from the Options Menu on the right side.</p>
+
+<p>You can enable items from your activity's Options Menu to appear directly in the Action Bar as
+"action items" by adding {@code showAsAction="ifRoom"} to specific items in your <a
+href="{@docRoot}guide/topics/resources/menu-resource.html">menu resource</a>. You can also add
+navigation features to the Action Bar, such as tabs, and use the application icon to navigate to
+your application's "home" activity or "up" the activity hierarchy.</p>
+
+<p>For more information, read <a href="{@docRoot}guide/topics/ui/actionbar.html">Using the
+Action Bar</a>.</p>
+
+
+
+<h3>Divide your activities into fragments</h3>
+
+<p>A fragment represents a behavior or a portion of user interface in an activity. You can combine
+multiple fragments in a single activity to build a multi-pane UI and reuse a fragment in multiple
+activities. You can think of a fragment as a modular section of an activity, which has its own
+lifecycle, receives its own input events, and which you can add or remove while the activity is
+running.</p>
+
+<p>For example, a news application can use one fragment to show a list of articles on the left and
+another fragment to display an article on the right—both fragments appear in one activity,
+side by side, and each fragment has its own set of lifecycle callback methods and handles its own
+input events. Thus, instead of using one activity to select an article and another activity to
+read the article, the user can select an article and read it all within the same activity.</p>
+
+<p>For more information, read the <a
+href="{@docRoot}guide/topics/fundamentals/fragments.html">Fragments</a> document.</p>
+
+
+<h3>Use new animation APIs for transitions</h3>
+
+<p>An all new flexible animation framework allows you to animate arbitrary properties of any object
+(View, Drawable, Fragment, Object, or anything else). You can define several animation aspects
+(such as duration, repeat, interpolation, and more) for an object's int, float, and hexadecimal
+color values, by default. That is, when an object has a property field for one of these types, you
+can change its value over time to affect an animation.</p>
+
+<p>The {@link android.view.View} class also provides new APIs that leverage the new animation
+framework, allowing you to easily apply 2D and 3D transformations to views in your activity layout.
+New transformations are made possible with a set of object properties that define the view's layout
+position, orientation, transparency and more.</p>
+
+<p>For more information, read the <a
+href="{@docRoot}guide/topics/graphics/animation.html">Property Animation</a> document.</p>
+
+
+<h3>Enable hardware acceleration</h3>
+
+<p>You can now enable the OpenGL renderer for your application by setting {@code
+android:hardwareAccelerated="true"} in your manifest's <a
+href="{@docRoot}guide/topics/manifest/application-element.html">{@code <application>}</a>
+element or for individual <a href="{@docRoot}guide/topics/manifest/activity-element.html">{@code
+<activity>}</a> elements. Hardware acceleration results in smoother animations, smoother
+scrolling, and overall better performance and response to user interaction. When enabled, be sure
+that you thoroughly test your application on a device that supports hardware acceleration.</p>
+
+
+<h3>Enhance your app widgets</h3>
+
+<p>App widgets allow users to access information from your application directly from the Home
+screen and interact with ongoing services (such as preview their email and control music playback).
+Android 3.0 enhances these capabilities by enabling collections, created with widgets such as
+{@link android.widget.ListView}, {@link android.widget.GridView}, and the new {@link
+android.widget.StackView}. These widgets allow you to create more interactive app
+widgets, such as one with a scrolling list, and can automatically update their data through a {@link
+android.widget.RemoteViewsService}.</p>
+
+<p>Additionally, you should create a preview image of your app widget using the Widget Preview
+application (pre-installed in an Android 3.0 AVD) and reference it with the {@link
+android.appwidget.AppWidgetProviderInfo#previewImage android:previewImage} attribute, so that users
+can see what the app widget looks like before adding it to their Home screen.</p>
+
+
+<h3>Add other new features</h3>
+
+<p>Android 3.0 introduces many more APIs that you might find valuable for your
+application, such as drag and drop APIs, new Bluetooth APIs, a system-wide clipboard framework, a
+new graphics engine called Renderscript, and more.</p>
+
+<p>To learn more about the APIs mentioned above and more, see the <a
+href="{@docRoot}sdk/android-3.0.html">Android 3.0 Platform</a> document.</p>
+
+
+<h3>Publish your app for extra large screens</h3>
+
+<p>You should also decide whether your application is <em>only</em> for
+tablet-type devices (specifically, <em>xlarge</em> devices) or for all types of screen sizes.</p>
+
+<p>If you want your application to be available to all screen sizes (for example, for all
+phones and tablets), there's nothing you need to do. By default, an application with <a
+href="{@docRoot}guide/topics/manifest/uses-sdk-element.html#min">{@code
+android:minSdkVersion}</a> set to {@code "4"} or higher will resize to fit any screen size.</p>
+
+<p>If your application is <em>only</em> for <em>xlarge</em> screens, include the <a
+href="{@docRoot}guide/topics/manifest/supports-screens-element.html">{@code
+<supports-screens>}</a> element in your manifest and declare that the application supports
+only <em>xlarge</em> screens, by declaring all other sizes {@code "false"}. For example:</p>
+
+<pre>
+<manifest ... >
+ ...
+ <supports-screens android:smallScreens="false"
+ android:normalScreens="false"
+ android:largeScreens="false"
+ android:xlargeScreens="true" />
+ <application ... >
+ ...
+ <application>
+</manifest>
+</pre>
+
+<p>With this declaration, you indicate that your application does not support any screen size except
+extra large. External services such as Android Market may then use this information to filter your
+application from devices that do not have an extra large screen.</p>
+
+
+
+<h3>Look at some samples</h3>
+
+<p>Many of the new features and APIs that are described in the <a
+href="{@docRoot}sdk/android-3.0.html#api">Android 3.0 Platform Preview</a> also have accompanying
+samples that can help you understand how to use them. To get the samples, download them from the SDK
+repository using the Android SDK Manager. After downloading the samples ("Samples for SDK API 11"),
+you can find them in <code><sdk_root>/samples/android-11/</code>. The links below can help you
+find samples for the features you are interested in:</p>
+
+<ul>
+ <li><a href="{@docRoot}resources/samples/HoneycombGallery/index.html">Honeycomb Gallery</a>:
+Demonstrates many new APIs in Android 3.0, including fragments, the action bar, drag and drop, and
+animations.</li>
+ <li><a
+href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/index.html#Fragment">
+Fragments</a>: Various samples that demonstrate fragment layouts, back stack, restoring state, and
+more.</li>
+ <li><a
+href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/ActionBarMechanics.html"
+>Action Bar</a>: Samples that demonstrate various Action Bar features, such as tabs, logos, and
+action items.</li>
+ <li><a
+href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/content/ClipboardSample.
+html">Clipboard</a>: An example of how to use the clipboard for copy and paste operations.</li>
+ <li><a
+href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/DragAndDropDemo.html">
+Drag and Drop</a>: An example of how to perform drag and drop with new View events.</li>
+ <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/List15.html">
+Multi-choice List</a>: An example of how to provide multiple-choice selection for ListView and
+GridView.</li>
+ <li><a
+href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/LoaderThrottle.html">
+Content Loaders</a>: An example using new Loader APIs to asynchronously load data.</li>
+ <li><a
+href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/animation/index.html">
+Property Animation</a>: Several samples using the new animation APIs to animate object
+properties.</li>
+ <li><a
+href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/SearchViewActionBar.
+html">Search View Widget</a>: Example using the new search widget in the Action Bar (as an
+"action view").</li>
+ <li><a
+href="{@docRoot}resources/samples/Renderscript/index.html">Renderscript</a>: Contains several
+different applications that demonstrate using renderscript APIs for computations and 3D
+graphics.</li>
+</ul>
+
+++ /dev/null
-page.title=Getting Started with the Android 3.0 Preview
-@jd:body
-
-<p>Welcome to Android 3.0!</p>
-
-<p>Android 3.0 is the next major release of the Android platform and is optimized for larger screen
-devices, particularly tablets. We're offering a preview SDK so you can get a head-start developing
-applications for it or simply test and optimize your existing application for upcoming devices.</p>
-
-<p><strong>Be aware that:</strong></p>
-<ul>
- <li>The APIs in the preview SDK are <strong>not final</strong>. Some APIs may change in behavior
-or availability when the final SDK is made available.</li>
- <li>You <strong>cannot</strong> publish an application that's built against the preview
-SDK—you can only run an application built against the preview SDK on the Android
-emulator.</li>
- <li>The documentation on <a href="http://developer.android.com">developer.android.com</a>
-does <strong>not</strong> include the Android 3.0 documentation—to read the API reference and
-developer guides for Android 3.0, you must install the Android 3.0 preview documentation from
-the AVD and SDK Manager.</li>
-</ul>
-
-
-
-<h3>How do I start?</h3>
-
-<ol>
- <li><a href="#Setup">Set up the preview SDK</a></li>
- <li>Then choose your app adventure:
- <ol type="a">
- <li><a href="#Optimize">Optimize Your App for Tablets and Similar Devices</a>
- <p>When you have an existing application and you want to maintain compatibility with
-older versions of Android.</p>
- </li>
- <li><a href="#Upgrade">Upgrade or Develop a New App for Tablets and Similar Devices</a>
- <p>When you want to upgrade your application to use APIs introduced in Android 3.0 or
- create a new application targeted to tablets and similar devices.</p></li>
- </ol>
- </li>
-</ol>
-
-<h3>Code samples</h3>
-<p>Many of the new features and APIs that are described in the <a href="{@docRoot}sdk/android-3.0.html#api">
-Android 3.0 Platform Preview</a> also have accompanying samples that help you understand how to use them.
-To get the samples, download them from the SDK repository using the Android SDK Manager. After download
-the samples are located in <code><sdk_root>/samples/android-Honeycomb</code>. The list of links
-below helps you find samples for the features you are interested in:</p>
-<ul>
- <li><a href="{@docRoot}resources/samples/HoneycombGallery/index.html">Honeycomb Gallery</a> -
- A demo application highlighting how to use some of the new APIs in Honeycomb, including fragments, the action bar,
- drag and drop, transition animations, and a stack widget.</li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/index.html#Fragment">Fragments</a>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/ActionBarMechanics.html">Action Bar</a></li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/content/ClipboardSample.html">Clipboard</a></li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/DragAndDropDemo.html">Drag and Drop</a></li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/List15.html">
- Multiple-choice selection for ListView and GridView</a></li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/app/LoaderThrottle.html">Content Loaders</a></li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/animation/index.html">Property Animation</a></li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/SearchViewActionBar.html">Search View Widget</a></li>
- <li><a href="{@docRoot}resources/samples/ApiDemos/src/com/example/android/apis/view/PopupMenu1.html">Popup Menu Widget</a></li>
-</ul>
-
-
-<h2 id="Setup">Set Up the Preview SDK</h2>
-
-<p>To start using the Android 3.0 preview SDK, set up your existing Android SDK with the new
-platform:</p>
-<p>(If you don't have an existing SDK, <a href="{@docRoot}sdk/index.html">download it
-now</a>.)</p>
-<ol>
- <li><a href="{@docRoot}sdk/adding-components.html#launching">Launch the Android SDK and AVD
-Manager</a> and install the following:
- <ul>
- <li>SDK Platform Android 3.0 Preview</li>
- <li>Android SDK Tools, revision 9</li>
- <li>Documentation for Android 'Honeycomb' Preview</li>
- <li>Samples for SDK API Honeycomb Preview</li>
- </ul>
- </li>
- <li><a href="{@docRoot}guide/developing/other-ide.html#AVD">Create an AVD</a> for tablets: set
-the target to "Android 3.0 (Preview)" and the skin to "WXGA".</li>
-</ol>
-
-
-<h3>About emulator performance</h3>
-
-<p>Because the Android emulator must simulate the ARM instruction set architecture on your
-computer and the WXGA screen is significantly larger than what the emulator
-normally handles, emulator performance is much slower than usual.</p>
-
-<p>In particular, initializing the emulator can be slow and can take several
-minutes, depending on your hardware. When the emulator is booting there is
-limited user feedback, so please be patient and continue waiting until you see
-the home screen appear. </p>
-
-<p>Note that you do not need to do a full boot of your emulator each time you
-rebuild your application — typically you only need to boot at the start of
-a session. See the Tips section below for information about using Snapshots to
-cut startup time after first initialization. </p>
-
-<p>We're working hard to resolve the performance issues and it will improve in future releases.
-Unfortunately, the emulator will perform slowly during your trial with the preview SDK. For the time
-being, the emulator is still best way to evaluate your application's appearance and functionality on
-Android 3.0.</p>
-
-<p class="note"><strong>Tip:</strong> To improve the startup time for the emulator, enable
-snapshots for the AVD when you create it with the SDK and AVD Manager (there's a checkbox in
-the GUI). Then, start the AVD from the manager and check <b>Launch from snapshot</b> and <b>Save to
-snapshot</b>. This way, when you close the emulator, a snapshot of the AVD state is saved and
-used to quickly relaunch the AVD next time. However, when you choose to save a snapshot, the
-emulator will be slow to close, so you might want to enable <b>Save to
-snapshot</b> only for the first time you launch the AVD.</p>
-
-
-<h3>Known issues</h3>
-
-<p>The following known issues occur for Android 3.0 AVDs that are loaded in the emulator:</p>
- <ul>
- <li>You cannot take screenshots of an emulator screen. The Device Screen
- Capture window displays <strong>Screen not available</strong>.</li>
- <li>The emulator cannot receive incoming SMS messages.</li>
- <li>GPS emulation is currently not supported.</li>
- <li>When rotating the emulator screen by pressing Ctrl-F11, the screen turns green momentarily,
-then displays the normal interface.</li>
- <li>In some circumstances, the emulator displays a rotated portrait screen while in landscape
-mode. To view the screen correctly, rotate the emulator to portrait mode by pressing Ctrl-F11 or
-turn off the auto-rotate setting in <strong>Settings > Screen > Auto-rotate screen</strong>.</li>
- <li>The Dev Tools application sometimes crashes when trying to use the Package Browser
-feature.</li>
- <li>On Ubuntu 10.04 64-bit machines, you cannot create an AVD that has an SD card.</li>
- </ul>
-
-
-
-<h2 id="Optimize">Optimize Your Application for Tablets and Similar Devices</h2>
-
-<p>If you've already developed an application for Android, there are a few things you can do
-to optimize it for a tablet-style experience, without changing the minimum platform version required
-(you don't need to change the manifest {@code minSdkVersion}).</p>
-
-<p class="note"><strong>Note:</strong> All Android applications are forward-compatible, so
-there's nothing you <em>have to</em> do—if your application is a good citizen of the Android
-APIs, your app should work fine on devices running Android 3.0. However, in order to provide users
-a better experience when running your app on an Android 3.0 tablet or similar-size device, we
-recommend that you update your application to adapt to the new system theme and optimize your
-application for larger screens.</p>
-
-<p>Here's what you can do to optimize your application for tablets running Android
-3.0:</p>
-
-<ol>
- <li><b>Test your current application on Android 3.0</b>
- <ol>
- <li>Build your application as-is and install it on your WXGA AVD (created above).</li>
- <li>Perform your usual tests to be sure everything works and looks as expected.</li>
- </ol>
- </li>
-
- <li><b>Apply the new "holographic" theme to your application</b>
- <ol>
- <li>Open your manifest file and update the <a
-href="{@docRoot}guide/topics/manifest/uses-sdk-element.html">{@code <uses-sdk>}</a> element to
-set {@code android:targetSdkVersion} to {@code "Honeycomb"}. For example:
-<pre>
-<manifest ... >
- <uses-sdk android:minSdkVersion="4"
- android:targetSdkVersion="Honeycomb" />
- <application ... >
- ...
- <application>
-</manifest>
-</pre>
- <p class="note"><strong>Note:</strong> The API Level value "Honeycomb" is a provisional API
-Level that is valid only while testing against the preview SDK. You
-<strong>should not</strong> publish your application using this API Level. When the final version of
-the Android 3.0 SDK is made available, you must change this value to the real API Level that will be
-specified for Android 3.0. For more information, read about <a
-href="{@docRoot}guide/appendix/api-levels.html">Android API Levels</a>.</p>
- <p>By targeting the Android 3.0 platform, the system automatically applies the Holographic theme
-to each of your activities, when running on an Android 3.0 device.</p>
- </li>
- <li>Continue to build against your application's {@code minSdkVersion}, but install it
-on the Android 3.0 AVD. Perform more testing on your application to be sure that your user interface
-works well with the Holographic theme.
- <p class="note"><strong>Note:</strong> If you've applied themes to your activities already,
-they will override the Holographic theme that the system applies when you set the {@code
-android:targetSdkVersion} to {@code "Honeycomb"}.
-Once the Android 3.0 APIs are finalized and an official API Level is assigned, you can use
-the <a href="{@docRoot}guide/topics/resources/providing-resources.html#VersionQualifier">system
-version qualifier</a> to provide an alternative theme that's based on the Holographic theme when
-your application is running on Android 3.0.</p>
- </ol>
- </li>
-
- <li><b>Supply alternative layout resources for xlarge screens</b>
- <p>As discussed in the guide to <a
-href="{@docRoot}guide/practices/screens_support.html">Supporting Multiple Screens</a>, Android
-2.3 and above support the <code>xlarge</code> resource qualifier, which you should use to supply
-alternative layouts for extra large screens.</p>
- <p>By providing alternative layouts for some of your activities when running on extra large
-screens, you can improve the user experience of your application on a tablet without using any
-new APIs.</p>
- <p>For example, here are some things to consider when creating a new layout for tables:</p>
- <ul>
- <li>Landscape layout: The "normal" orientation for tablets is usually landscape (wide), so
-you should be sure that your activities offer an appropriate layout for such a wide viewing
-area.</li>
- <li>Button position: Consider whether the position of the most common buttons in your UI are
-easily accessible while holding a tablet with two hands.</li>
- </ul>
- </li>
-</ol>
-
- <p>In general, always be sure that your application follows the <a
-href="{@docRoot}guide/practices/screens_support.html#screen-independence">Best Practices
-for Screen Independence</a>.</p>
-
-
-<h2 id="Upgrade">Upgrade or Develop a New App for Tablets and Similar Devices</h2>
-
-<p>If you want to develop something truly for tablet-type devices running Android 3.0, then you need
-to use new APIs available in Android 3.0. This section introduces some of the new features that you
-should use.</p>
-
-<p>The first thing to do when you create a project with the Android 3.0 preview is set the <a
-href="{@docRoot}guide/topics/manifest/uses-sdk-element.html">{@code <uses-sdk>}</a> element to
-use {@code "Honeycomb"} for the {@code android:minSdkVersion}. For example:</p>
-
-<pre>
-<manifest ... >
- <uses-sdk android:minSdkVersion="Honeycomb" />
- <application ... >
- ...
- <application>
-</manifest>
-</pre>
-
-<p class="note"><strong>Note:</strong> The API Level value "Honeycomb" is a provisional API
-Level that is valid only while building and testing against the preview SDK. You
-<strong>cannot</strong> publish your application using this API Level. When the final version of the
-Android 3.0 SDK is made available, you must change this value to the real API Level that is
-specified for Android 3.0. For more information, read about <a
-href="{@docRoot}guide/appendix/api-levels.html">Android API Levels</a>.</p>
-
-<p>Be sure that the <a href="{@docRoot}guide/topics/manifest/uses-sdk-element.html">{@code
-<uses-sdk>}</a> element appears <strong>before</strong> the <a
-href="{@docRoot}guide/topics/manifest/application-element.html">{@code <application>}</a>
-element.</p>
-
-<p>By targeting the Android 3.0 platform (and declaring it before <a
-href="{@docRoot}guide/topics/manifest/application-element.html">{@code <application>}</a>),
-the system automatically applies the new Holographic theme to each of your
-activities.</p>
-
-
-
-<h3>Publishing your app for tablet-type devices only</h3>
-
-<p>Additionally, you should decide whether your application is for <em>only</em> tablet devices
-(specifically, <em>xlarge</em> devices) or for devices of all sizes that may run Android 3.0.</p>
-
-<p>If your application is <em>only</em> for tablets (<em>xlarge</em> screens; not for mobile
-devices/phones), then you should include the <a
-href="{@docRoot}guide/topics/manifest/supports-screens-element.html">{@code
-<supports-screens>}</a> element in your manifest with all sizes except for xlarge declared
-false. For example:</p>
-
-<pre>
-<manifest ... >
- <uses-sdk android:minSdkVersion="Honeycomb" />
- <supports-screens android:smallScreens="false"
- android:normalScreens="false"
- android:largeScreens="false"
- android:xlargeScreens="true" />
- <application ... >
- ...
- <application>
-</manifest>
-</pre>
-
-<p>With this declaration, you indicate that your application does not support any screen size except
-extra large. External services such as Android Market may use this to filter your application
-from devices that do not have an extra large screen.</p>
-
-<p>Otherwise, if you want your application to be available to both small devices (phones) and large
-devices (tablets), do <em>not</em> include the <a
-href="{@docRoot}guide/topics/manifest/supports-screens-element.html">{@code
-<supports-screens>}</a> element.</p>
-
-<div class="special">
-<p>To learn more about some of the new APIs,
-see the <a href="{@docRoot}sdk/android-3.0.html">Android 3.0 Platform Preview</a> document.</p>
-</div>