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diff --git a/docs/html/sdk/preview/index.jd b/docs/html/sdk/preview/index.jd index 81b4ff6..edfa02b 100644 --- a/docs/html/sdk/preview/index.jd +++ b/docs/html/sdk/preview/index.jd @@ -1,4 +1,183 @@ -sdk.redirect=true - +page.title=Android 3.0 Preview SDK @jd:body +<p>Android 3.0 is the next major release of the Android platform and is optimized for tablet +devices. We're offering a Preview SDK so you can get a head-start developing +applications for it or simply optimize your existing application for upcoming +tablets.</p> + + +<h3>What is the Preview SDK?</h3> + +<p>The Android 3.0 Preview SDK is an early look at the upcoming version of Android 3.0, for +developers only. </p> + +<p>The Preview SDK includes:</p> +<ul> + <li>An early Android 3.0 system image for use in the Android emulator</li> + <li>An Android 3.0 library with non-final APIs</li> + <li>A new WXGA emulator skin for an extra large Android Virtual Device</li> + <li>New documentation for Android 3.0, including a complete API reference, new developer guides, +and an API differences report between Android 3.0 and 2.3.</li> +</ul> + +<div class="note"> +<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> +</div> + + +<p><b>About emulator performance</b></p> + +<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>We're working hard to resolve the performance issues in the emulator and it will improve in +future releases. In the meantime, we wanted to give developers access to new APIs and an basic test +environment as early as possible. </p> + +<p>Keeping in mind that performance on the emulator does not reflect the speed or performance of +apps on actual devices running Android 3.0, developing and testing on the emulator is still an +important tool in evaluating your application's appearance and functionality on the new platform. +</p> + + + + + +<h3>What can I do with the preview?</h3> + +<p>The Preview SDK is intended for testing existing applications on the new platform and +developing new applications with new Android 3.0 APIs.</p> + +<p>If you have an existing Android application, you don't <em>have to</em> do anything. Android +applications are always forward-compatible. If your application is a good citizen of the Android +APIs, your app should work fine on devices running Android 3.0 without any additional work. However, +in order to ensure proper performance and provide users a better experience when running your +application on an Android 3.0 tablet, we recommend that you perform the following:</p> + +<ol> + <li><b>Test your application on Android 3.0</b> + <p>Simply install the Android 3.0 preview in your Android SDK, create an AVD using the +Android 3.0 system image, install your application, and run some tests.</p> + <p>As mentioned above, your application should perform as expected. You might, however, +discover that your activity layouts are less than ideal on a large screen or some other aspects +of your application don't behave the way you expect.</p> + </li> + <li><b>Inherit the new "Holographic" theme</b> + <p>Android 3.0 offers an updated set of UI widgets that are redesigned for use on larger screens +such as tablets and incorporate the new holographic theme. Your existing application can inherit +the new design simply by setting the <a +href="{@docRoot}guide/topics/manifest/uses-sdk-element.html">{@code <uses-sdk>}</a> +element's {@code android:targetSdkVersion} attribute to {@code "Honeycomb"}.</p> + <p>If you do not update the {@code android:targetSdkVersion} attribute and the {@code +android:minSdkVersion} is set to "9" or lower, then your application uses the widget designs +from Android 2.3 and does <em>not</em> inherit the holographic theme.</p> + <p>In order for your application to match the rest of the system UI, we highly recommend you +make this change to inherit the new widget styles and system theme. However, beware that doing so +might conflict with color or text designs you applied to your application based on the previous +system theme, so you should be sure to inspect your application UI when using the holographic +theme.</p> + </li> + <li><b>Provide alternative layouts for extra large 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> + <p class="note"><strong>Note:</strong> You can add alternative resources for <em>xlarge</em> +screens without changing your {@code minSdkVersion}. For example, if you add alternative layouts in +<code>res/layout-xlarge/</code> and your application is compatible with older versions, such +as Android 1.5—which doesn't support <em>xlarge</em> screens—this layout directory is +simply ignored by those devices.</p> + </li> +</ol> + + +<p>Otherwise, if you want to develop a new application or upgrade your existing application to +use APIs added in Android 3.0, we encourage you to get started by developing against the Android +3.0 preview platform. You can get started the same way as you would for any other version of +Android.</p> + + +<p>To get started—whether testing an existing application or creating a new one—follow +the procedure in the following section to install the Preview SDK.</p> + + + +<h3 id="Setup">How do I get it?</h3> + +<p>To get the Preview SDK, you can download it using the Android SDK and AVD Manager.</p> + +<p>If you're new to Android development, start by <a href="{@docRoot}sdk/index.html">downloading the +Android SDK starter package</a>.</p> + +<p><a href="{@docRoot}sdk/adding-components.html#launching">Launch the Android SDK and AVD +Manager</a> and install the following:</p> +<ul> + <li>SDK Platform Android Honeycomb Preview</li> + <li>Android SDK Tools, revision 9</li> + <li>Android SDK Platform-tools, revision 2</li> + <li>Documentation for Android 'Honeycomb' Preview</li> + <li>Samples for SDK API Honeycomb Preview</li> +</ul> + +<p class="note"><strong>Note:</strong> Be sure to install the documentation component for the +Honeycomb Preview SDK. The API reference for the Android 3.0 API is <strong>not</strong> available +online.</p> + +<p>Once you have installed these components, open your SDK directory and navigate to {@code +docs/sdk/} and open {@code index.html} in your browser. </p> + + + +<h3 id="Issues">Known issues</h3> + +<p>The following known issues occur for Android 3.0 AVDs that are loaded in the emulator:</p> + +<ul> + <li>The emulator displays a rotated portrait screen while in landscape +orientation. To view the screen correctly in landscape orientation, turn off the auto-rotate setting +in <strong>Settings > Screen > Auto-rotate screen</strong>. Then use Ctrl-F11 to rotate the +emulator.</li> + <li>You cannot take screenshots of an emulator screen. The Device Screen Capture window displays +<strong>Screen not available</strong>.</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>The Dev Tools application sometimes crashes when trying to use the Package Browser +feature.</li> +</ul> + + +<div class="special"> + <p>For an overview of new features in Android 3.0, read the <a +href="{@docRoot}sdk/android-3.0-highlights.html">Platform Highlights</a>.</p> +</div> + |