701 lines
33 KiB
Plaintext
701 lines
33 KiB
Plaintext
page.title=L Developer Preview APIs
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excludeFromSuggestions=true
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sdk.platform.apiLevel=20
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@jd:body
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<div id="qv-wrapper">
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<div id="qv">
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<h2>In this document
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<a href="#" onclick="hideNestedItems('#toc44',this);return false;" class="header-toggle">
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<span class="more">show more</span>
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<span class="less" style="display:none">show less</span></a></h2>
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<ol id="toc44" class="hide-nested">
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<li><a href="#Behaviors">Important Behavior Changes</a>
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<ol>
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<li><a href="#BehaviorNotifications">If your app implements notifications...</a></li>
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<li><a href="#BehaviorFullscreen">If your app uses fullScreenIntent...</a></li>
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<li><a href="#BehaviorGetRecentTasks">If your app uses ActivityManager.getRecentTasks()...</a></li>
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</ol>
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</li>
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<li><a href="#UI">User Interface</a>
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<ol>
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<li><a href="#MaterialDesign">Material design support</a></li>
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<li><a href="#LockscreenNotifications">Lockscreen notifications</a></li>
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<li><a href="#NotificationsMetadata">Notifications metadata</a></li>
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<li><a href="#Recents">Concurrent documents and activities in Recents screen</a></li>
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<li><a href="#WebView">WebView updates</a></li>
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</ol>
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</li>
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<li><a href="#UserInput">User Input</a>
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<ol>
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<li><a href="#IME">IME bug fixes and improvements</a></li>
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</ol>
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</li>
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<li><a href="#Animations">Animation & Graphics</a>
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<ol>
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<li><a href="#OpenGLES-3-1">Support for OpenGL ES 3.1</a></li>
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</ol>
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</li>
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<li><a href="#Multimedia">Multimedia</a>
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<ol>
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<li><a href="#Camera-v2">Camera V2</a></li>
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<li><a href="#AudioPlayback">Audio playback</a></li>
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<li><a href="#MediaPlaybackControl">Media playback control</a></li>
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</ol>
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</li>
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<li><a href="#Storage">Storage</a>
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<ol>
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<li><a href="#DirectorySelection">Directory selection</a></li>
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</ol>
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</li>
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<li><a href="#Wireless">Wireless and Connectivity</a>
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<ol>
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<li><a href="#Multinetwork">Dynamic network selection and seamless handoff</a></li>
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<li><a href="#BluetoothBroadcasting">Bluetooth broadcasting</a></li>
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<li><a href="#NFCEnhancements">NFC enhancements for payments</a></li>
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</ol>
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</li>
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<li><a href="#Power">Power Efficiency</a>
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<ol>
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<li><a href="#JobScheduler">Scheduling Jobs</a></li>
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<li><a href="#PowerMeasurementTools">Developer tools and APIs for power measurement</a>
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</ol>
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</li>
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<li><a href="#Enterprise">Enterprise</a>
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<ol>
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<li><a href="#ManagedProvisioning">Managed provisioning</a></li>
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</ol>
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</li>
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<li><a href="#Printing">Printing Framework</a>
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<ol>
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<li><a href="#PDFRender">PDF rendering</a></li>
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</ol>
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</li>
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<li><a href="#TestingA11y">Testing & Accessibility</a>
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<ol>
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<li><a href="#TestingA11yImprovements">Testing and accessibility improvements</a></li>
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</ol>
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</li>
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<li><a href="#Manifest">Manifest Declarations</a>
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<ol>
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<li><a href="#ManifestFeatures">Declarable required features</a></li>
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<li><a href="#ManifestPermissions">User permissions</a></li>
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</ol>
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</li>
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</ol>
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<h2>See also</h2>
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<ol>
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<li><a href="{@docRoot}sdk/api_diff/20/changes.html">API
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Differences Report »</a> </li>
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</ol>
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</div>
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</div>
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<p>L is an upcoming release for the Android platform
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that offers new features for users and app developers. This document provides
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an introduction to the most notable new APIs.</p>
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<p>L is currently available as a <strong>developer preview</strong> intended
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for early adopters and testers. If you are interested in influencing the
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direction of the Android framework,
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<a href="{@docRoot}preview/setup-sdk.html">give the L Developer Preview a
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try</a> and send us your feedback!</p>
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<p class="caution"><strong>Caution:</strong>You should not publish apps
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using L Developer Preview to the Google Play store.</p>
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<h2 id="Behaviors">Important Behavior Changes</h2>
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<p>If you have previously published an app for Android, be aware that your app
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might be affected by changes in L.</p>
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<h3 id="BehaviorNotifications">If your app implements notifications...</h3>
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<p>Notifications will be drawn with dark text atop white (or very light)
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backgrounds to match the new material design widgets. Make sure that all your
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notifications look right with the new color scheme. You should remove or update
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assets and text styles that involve color. The system will automatically invert
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action icons in notifications. Use
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{@code android.app.Notification.Builder.setColor()} to set an accent color
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in a circle behind your {@code Notification.icon} image.</p>
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<p>The system will ignore all non-alpha channels in action icons and the main
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notification icon, so you should assume that these icons will be alpha-only.
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</p>
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<p>If you are currently adding sounds and vibrations to your notifications by
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using the {@link android.media.Ringtone}, {@link android.media.MediaPlayer},
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or {@link android.os.Vibrator} classes, make sure to remove this code so that
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the system can present notifications correctly in Do not disturb mode. You
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should use the {@link android.app.Notification.Builder} methods instead to add
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sounds and vibration.
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</p>
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<h3 id="BehaviorMediaControl">If your app uses RemoteControlClient...</h3>
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<p>Lockscreens in L will not show transport controls for your
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{@link android.media.RemoteControlClient}. Instead, your app can provide
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media playback control from the lockscreen through a media notification. This
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gives your app more control over the presentation of media buttons, while
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providing a consistent experience for users across the lockscreen and
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unlocked device.</p>
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<p>You must call {@code Notification.Builder.setVisibility(Notification.VISIBILITY_PUBLIC)} to mark your media notification as safe to reveal, even when the lockscreen is secured
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with a PIN, pattern, or password.</p>
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<h3 id="BehaviorFullscreen">If your app uses fullScreenIntent...</h3>
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<p>Notifications now appear in a small floating window if all these conditions
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are met: the user’s activity is in fullscreen mode, the screen is on, and the
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device is unlocked. If your app implements fullscreen activities, make sure that
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these heads-up notifications are presented correctly.</p>
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<h3 id="BehaviorGetRecentTasks">If your app uses ActivityManager.getRecentTasks()...</h3>
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<p>With the introduction of the new document tasks feature in L (see below),
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the {@code android.app.ActivityManager.getRecentTasks()} method is now
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deprecated to improve user privacy. For backwards
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compatibility, it will still return a small subset of its data including the
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calling application’s own tasks and possibly some other non-sensitive tasks
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such as home. If your app is using this method to retrieve its own tasks,
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use {@code android.app.ActivityManager.getAppTasks()} instead to retrieve that
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information.</p>
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<h2 id="UI">User Interface</h2>
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<h3 id="MaterialDesign">Material design support</h3>
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<p>L adds support for the material design style. You can create
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material design apps that are visually dynamic and have UI element transitions
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which feel natural and delightful to users. This support includes:</p>
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<ul>
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<li>Material design theme
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<li>View shadows
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<li>{@code RecyclerView} widget
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<li>Drawable animation and styling effects
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<li>Material design animation and activity transitions effects
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<li>Ability to define animators to run on the view, with
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{@code android.animation.StateListAnimator}.
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<li>Ability to change your status bar color to match the action bar and other
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UI elements with {@code android.view.Window.setStatusBarColor()}.
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</ul>
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<p>To learn more about adding material design functionality to your app, see
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<a href="{@docRoot}preview/material/index.html">Material design on Android</a>.</p>
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<h3 id="LockscreenNotifications">Lockscreen notifications</h3>
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<p>Lockscreens in L Developer Preview have the ability to present notifications.
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User can choose via <em>Settings</em> whether to allow sensitive notification
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content to be shown over a secure lockscreen.</p>
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<p>Your app can control the level of detail visible when its notifications are
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displayed over the secure lockscreen.To control the visibility level, call
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{@code android.app.Notification.Builder.setVisibility()} and specify one of these
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values:</p>
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<ul>
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<li>{@code VISIBILITY_PRIVATE}. Shows basic information, such as the
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notification’s icon, but hides the notification’s full content. If you want to
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provide a redacted public version of your notification for the system to display
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on a secure lockscreen, set the public notification object in the publicVersion
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field.
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<li>{@code VISIBILITY_PUBLIC}. Shows the notification’s full content. This is
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the system default if visibility is left unspecified.
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<li>{@code VISIBILITY_SECRET}. Shows only the most minimal information,
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excluding even the notification’s icon.
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</ul>
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<h3 id="NotificationsMetadata">Notifications metadata</h3>
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<p>The L Developer Preview uses metadata associated with your app notifications
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to more intelligently sort your notifications. The metadata you set also
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controls how the system presents your app notifications when the user is in Do
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not disturb mode. When constructing your notification, you can call the
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following methods in {@code android.app.Notification.Builder}:</p>
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<ul>
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<li>{@code setCategory()}. Allows the system to handle your app notifications
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in Do not disturb mode (for example, if your notification represents an
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incoming call, instant message, or alarm).
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<li>{@code setPriority()}. Notifications with the priority field set to
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{@code PRIORITY_MAX} or {@code PRIORITY_HIGH} will appear in a small floating
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window if the notification also has sound or vibration.
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<li>{@code addPerson()}. Allows you to add a list of people to a notification.
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Your app can use this to signal to the system that it should group together
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notifications from the specified people, or rank notifications from these
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people as being more important.
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</ul>
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<h3 id="Recents">Concurrent documents and activities in Recents screen</h3>
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<p>In previous releases, the
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<a href="{@docRoot}design/get-started/ui-overview.html">Recents screen</a>
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could only display a single task for each app that the user interacted with
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most recently. The L Developer Preview allows your app to open additional tasks
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for concurrent activities or documents. This feature facilitates multitasking
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by letting users quickly switch between individual activities and documents
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from the Recents screen. Examples of such concurrent tasks might include web
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pages in a browser app, documents in a productivity app, concurrent matches in
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a game, or chats in a messaging app. Your app can manage its tasks
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through the {@code android.app.ActivityManager.AppTask} class.</p>
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<p>To insert a logical break so that the system treats your activity as a new
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document, use {@code android.content.Intent.FLAG_ACTIVITY_NEW_DOCUMENT} when
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launching the activity with {@link android.app.Activity#startActivity(android.content.Intent) startActivity()}. You can also get this behavior by declaring the
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<a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a>
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attribute {@code documentLaunchMode="intoExisting"} or {@code ="always"} in your
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manifest.</p>
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<p>You can also mark that a task should be removed from the Recents screen
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when all its activities are closed by using {@code android.content.Intent.FLAG_ACTIVITY_AUTO_REMOVE_FROM_RECENTS} when starting the root activity for
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the task. You can also set this behavior for an activity by declaring the
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<a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a>
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attribute {@code autoRemoveFromRecents=“true”} in your manifest.</p>
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<p>To avoid cluttering the Recents screen, you can set the maximum number of
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tasks from your app that can appear in the Recents screen through the
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<a href="{@docRoot}guide/topics/manifest/application-element.html"><application></a> attribute {@code android:maxRecent}. The current maximum that can be specified
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is 100 tasks per user.</a></p>
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<h3 id="WebView">WebView updates</h3>
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<p>The L Developer Preview updates the {@link android.webkit.WebView}
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implementation to Chromium M36, bringing security and stability enhancements,
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as well as bug fixes. The default user-agent string for a
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{@link android.webkit.WebView} running on the L Developer Preview has
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been updated to incorporate 36.0.0.0 as the version number.</p>
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<p>Additionally, this release brings support for the
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<a href="https://dvcs.w3.org/hg/audio/raw-file/tip/webaudio/specification.html">WebAudio</a>, <a href="https://www.khronos.org/webgl/">WebGL</a>, and
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<a href="http://www.webrtc.org/">WebRTC</a> open standards. To learn more about
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the new features included in this release, see <a href="https://developer.chrome.com/multidevice/webview/overview">WebView for Android</a>.</p>
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<h2 id="UserInput">User Input</h2>
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<h3 id="IME">IME bug fixes and improvements</h3>
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<p>Beginning in the L Developer Preview, users can more easily switch between
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all input method editors (IME) <a href="{@docRoot}guide/topics/text/creating-input-method.html">supported by the platform</a>. Performing the designated
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switching action (usually touching a Globe icon on the soft keyboard) will cycle
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among all such IMEs. This change takes place in
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{@code android.view.inputmethod.InputMethodManager.shouldOfferSwitchingToNextInputMethod()}.</p>
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<p>In addition, the framework will now check whether the next IME includes a
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switching mechanism at all, thus supporting switching to the IME after it. An
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IME with a switching mechanism will not cycle to an IME without one. This
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change takes place in
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{@code android.view.inputmethod.InputMethodManager.switchToNextInputMethod()}.
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<p>To see an example of how to use the updated IME-switching APIs, refer to the
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updated soft-keyboard implementation sample in this release.</p>
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<h2 id="Animations">Animation & Graphics</h2>
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<h3 id="OpenGLES-3-1">Support for OpenGL ES 3.1</h3>
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<p>The L Developer Preview adds Java interfaces and native support for OpenGL
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ES 3.1. Key new functionality provided in OpenGL ES 3.1 includes:</p>
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<ul>
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<li>Compute shaders
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<li>Separate shader objects
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<li>Indirect draw commands
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<li>Enhanced texturing functionality
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<li>Shading language improvements
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<li>Optional extensions for per-sample shading, advanced blending modes, and more
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<li>Backward compatibility with OpenGL ES 2.0 and 3.0
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</ul>
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<p>The Java interface for OpenGL ES 3.1 on Android is provided with GLES31. When using OpenGL ES 3.1, be sure that you declare it in your manifest file with the
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<a href="{@docRoot}guide/topics/manifest/uses-feature-element.html">{@code <uses-feature>}</a> tag and the {@code android:glEsVversion} attribute. For example:</p>
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<pre>
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<manifest>
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<uses-feature android:glEsVersion="0x00030001" />
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...
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</manifest>
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</pre>
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<p>For more information about using OpenGL ES, including how to check the device’s supported OpenGL ES version at runtime, see the <a href="{@docRoot}/guide/topics/graphics/opengl.html">OpenGL ES API guide</a>.</p>
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<h2 id="Multimedia">Multimedia</h2>
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<h3 id="Camera=v2">Camera v2 API</h3>
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<p>The L Developer Preview introduces the new {@code android.hardware.camera2}
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API to facilitate fine grain photo capture and image processing. You can now programmatically access the camera devices available to the system with {@code CameraManager.getCameraIdList()} and connect to a specific device with {@code CameraManager.openCamera()}. To start capturing images, you
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need to create a {@code CameraCaptureSession} and specify the
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{@link android.view.Surface} objects to send the captured images. The {@code CameraCaptureSession} can be configured to take single shots or multiple images
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in a burst.</p>
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<p>To be notified when new images are captured, implement the
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{@code CameraCaptureSession.CaptureListener()} interface and set it in your
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capture request. Now when the system completes the image capture request, your
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{@code CameraCaptureSession.CaptureListener()} receives a call to
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{@code onCaptureCompleted()}, providing you with the image capture metadata in a
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{@code CaptureResult}.</p>
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<h3 id="AudioPlayback">Audio playback</h3>
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<p>This release includes the following changes for
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{@code android.media.AudioTrack}:</p>
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<ul>
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<li>Your app can now supply audio data in floating-point format
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({@code android.media.AudioFormat.ENCODING_PCM_FLOAT}). This permits greater
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dynamic range, more consistent precision, and greater headroom. Floating-point arithmetic is especially useful during intermediate calculations. Playback
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end-points use integer format for audio data, and with lower bit-depth. In L
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Developer Preview, portions of the internal pipeline are not yet floating-point.
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<li>Your app can now supply audio data as a {@code ByteBuffer}, in the same
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format as provided by {@code MediaCodec}.
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<li>The {@code WRITE_NON_BLOCKING} option can simplify buffering and
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multithreading for some apps.
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</ul>
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<h3 id="MediaPlaybackControl">Media playback control</h3>
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<p>You can now build your own media controller app with the new
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{@code android.media.session.MediaController} class, which provides
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simplified transport controls APIs that replace those in
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{@code android.media.RemoteControlClient}. The {@code MediaController} class
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allows thread-safe control of playback from a non UI process, making it easier
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to control your media playback service from your app’s user interface.
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<p>You can also create multiple controllers to send playback commands,
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media keys, and other events to the same ongoing
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{@code android.media.session.MediaSession}. When you add a controller, you must
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call {@code MediaSession.getSessionToken()} to request an access
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token in order for your app to interact with the session.</p>
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<p>Send transport commands such as "play", "stop", "skip", and
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"set rating" by using {@code MediaController.TransportControls}. To handle
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in-bound media transport commands from controllers attached to the session, you
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should override the callback methods in
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{@code MediaSession.TransportControlsCallback}.</p>
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<p>You can also create rich notifications that allow playback control tied to a
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media session with the new {@code android.app.Notification.MediaStyle} class.</p>
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<h2 id="Storage">Storage</h2>
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<h3 id="DirectorySelection">Directory selection</h3>
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<p>The L Developer Preview extends the <a href="{@docRoot}guide/topics/providers/document-provider.html">Storage Access Framework</a> to let users
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select an entire directory, rather than individual files, to give your app
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read/write access to media files. When a directory is selected, your app also
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has access to all its child directories and content.</p>
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<p>To get the absolute paths to directories on external storage devices where
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applications can store media files, call the
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{@code android.content.Context.getExternalMediaDirs()} method. No additional
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permissions are needed by your app to read or write to the returned paths.
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External storage devices here are those considered by the system to be a
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permanent part of the device, and includes emulated external storage and
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physical media slots such as SD cards in battery compartments.</p>
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<p>If you want to access a document in an existing directory, call the
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{@code android.provider.DocumentsContract.buildDocumentViaUri()} method and pass
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in a Uri representing the path to the parent directory and the target document
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ID. The method returns a new {@link android.net.Uri} with which your app can
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use to write media content with {@code DocumentsContract.createDocument()}.
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<h2 id="Wireless">Wireless & Connectivity</h2>
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||
<h3 id="Multinetwork">Dynamic network selection and seamless handoff</h3>
|
||
<p>The L Developer Preview provides new multi-networking APIs for your app to
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dynamically scan for available networks with specific capabilities, and
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establish a connection to them. This is useful when your app requires a
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specialized network, such as an SUPL, MMS, or carrier-billing network, or if
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you want to send data using a particular type of transport protocol.</p>
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<p>To select and connect to a network dynamically from your app, first
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instantiate a {@code android.net.ConnectivityManager}. Next, create a
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{@code android.net.NetworkRequest} to specify the network features and transport
|
||
type your app is interested in. To start scanning for suitable networks, call
|
||
{@code ConnectivityManager.requestNetwork()} or
|
||
{@code ConnectivityManager.registerNetworkCallback(), and pass in the
|
||
{@code NetworkRequest} object and an implementation of
|
||
{@code ConnectivityManager.NetworkCallbackListener}.</p>
|
||
|
||
<p>When the system detects a suitable network, it connects to the network and
|
||
invokes the {@code NetworkCallbackListener.onAvailable()} callback. You can use
|
||
the {@code android.net.Network} object from the callback to get additional
|
||
information about the network, or to establish a socket connection.</p>
|
||
|
||
<h3 id="BluetoothBroadcasting">Bluetooth broadcasting</h3>
|
||
<p>Android 4.3 introduced platform support for <a href="{@docRoot}guide/topics/connectivity/bluetooth-le.html">Bluetooth Low Energy</a>
|
||
(BLE) in the central role. In the L Developer Preview, an Android device can now
|
||
act as a Bluetooth LE <em>peripheral device</em> and make its presence known to
|
||
nearby devices. For instance, you can build apps that allow a device to
|
||
function as a pedometer or health monitor and communicate its data with another
|
||
BLE device.</p>
|
||
|
||
<p>The new {@code android.bluetooth.le} APIs enable your apps to broadcast advertisements, scan for responses, and form connections with nearby BLE devices.
|
||
You must add the {@code android.permission.BLUETOOTH_ADMIN} permission in your
|
||
manifest in order for your app to use the new advertising and scanning features.</a>
|
||
|
||
<p>To begin Bluetooth LE advertising so that other devices can discover the
|
||
device running your app, call {@code android.bluetooth.le.BluetoothAdvertiser.startAdvisertising()} and pass in an implementation of the
|
||
{@code android.bluetooth.le.AdvertiseCallback} class to report the success
|
||
or failure of the advertising operation.</p>
|
||
|
||
<p>Conversely, if you want to scan for Bluetooth LE devices nearby, call
|
||
{@code android.bluetooth.le.BluetoothLeScanner.startScan()} and pass in an
|
||
implementation of {@code android.bluetooth.le.ScanCallback} to report if a
|
||
Bluetooth LE advertisement is found. Optionally, you can pass in filters to scan
|
||
for a specific type of device.</p>
|
||
|
||
<h3 id="NFCEnhancements">NFC enhancements</h3>
|
||
<p>The L Developer Preview adds these enhancements to enable wider and more
|
||
flexible use of NFC:</p>
|
||
|
||
<ul>
|
||
<li>Android Beam is now available in the share menu.
|
||
<li>Support for the <a href="http://www.wi-fi.org/discover-wi-fi/wi-fi-direct">Wi-fi Direct standard</a>.
|
||
<li>Your app can invoke the Android Beam on the user’s device to share data by
|
||
calling {@code android.nfc.NfcAdapter.invokeBeam()}. This avoids the need for
|
||
the user to manually tap the device against another NFC-capable device to
|
||
complete the data transfer.
|
||
<li>Use the new {@code android.nfc.NdefRecord.createTextRecord()} method if
|
||
you want to create an NDEF record containing UTF-8 text data.
|
||
<li>If you are developing a payment app, you now have the ability to
|
||
register an NFC application ID (AID) dynamically by calling
|
||
{@code android.nfc.cardemulation.CardEmulation.registerAidsForService()}.
|
||
You can also use {@code android.nfc.cardemulation.CardEmulation.setPreferredService()}
|
||
to set the preferred card emulation service that should be used when a specific
|
||
activity is in the foreground.
|
||
</ul>
|
||
|
||
<h2 id="Power">Power Efficiency</h2>
|
||
|
||
<h3 id="JobScheduler">Scheduling jobs</h3>
|
||
<p>The L Developer Preview provides a new {@code android.app.job.JobScheduler}
|
||
API that lets you optimize battery life by defining jobs for the system to run
|
||
asynchronously at a later time, such as when the device is charging. This is
|
||
useful when you want to defer non user-facing units of work, have application
|
||
code that accesses the network, or want to run a number of tasks as a batch on
|
||
a regular schedule.</p>
|
||
|
||
<p>A {@code android.app.job.JobInfo} object encapsulates such a unit of work,
|
||
and provides an exact description of the criteria you are scheduling.</p>
|
||
|
||
<p>Use the {@code android.app.job.JobInfo.Builder} to configure how the
|
||
scheduled task should run. You can schedule the task to run under specific
|
||
conditions such as only while the device is charging, when connected to an
|
||
unmetered network, or when the system deems the device is idle.</p>
|
||
|
||
<p>For example, you can add code like this to run your task on an
|
||
unmetered network:</p>
|
||
|
||
<pre>
|
||
JobInfo uploadTask = new JobInfo.Builder(mJobId, mServiceComponent)
|
||
.setRequiredNetworkCapabilities(JobInfo.NetworkType.UNMETERED)
|
||
.build();
|
||
|
||
JobScheduler jobScheduler =
|
||
(JobScheduler) context.getSystemService(Context.JOB_SCHEDULER_SERVICE)
|
||
jobScheduler.schedule(uploadTask);
|
||
</pre>
|
||
|
||
<h3 id="PowerMeasurementTools">Developer tools and APIs for power measurement</h3>
|
||
<p>The L Developer Preview provides several new developer tools and APIs to help
|
||
you better measure and understand your app's power usage.</p>
|
||
|
||
<dl>
|
||
<dt><strong>batterystats</strong></dt>
|
||
<dd>
|
||
<p>The {@code dumpsys batterystats} command allows you to generate interesting
|
||
statistical data about battery usage on a device, organized by unique user ID
|
||
(UID). The statistics generated by the tool include:</p>
|
||
|
||
<ul>
|
||
<li>History of battery related events
|
||
<li>Global statistics for the device
|
||
<li>Approximated power use per UID and system component
|
||
<li>Per-app mobile ms per packet
|
||
<li>System UID aggregated statistics
|
||
<li>App UID aggregated statistics
|
||
</ul>
|
||
|
||
<p>Use the {@code --help} option to learn about the various options for
|
||
tailoring the output. For example, to run the tool to print battery usage
|
||
statistics since the device was last charged for a given app package, run this
|
||
command:
|
||
<pre>
|
||
$ adb shell dumpsys batterystats --charged <package-name>
|
||
</pre>
|
||
</dd>
|
||
|
||
<dt><strong>Battery Historian</strong></dt>
|
||
<dd>
|
||
<p>The Battery Historian tool ({@code historian.par}) analyzes L-based Android
|
||
bug reports and creates an HTML visualization of power-related events. It can
|
||
also visualize power consumption data from a power monitor, and will attempt to
|
||
map power usage to the wakelocks seen. You can find the Battery Historian tool
|
||
in {@code <sdk>/tools}.</p>
|
||
|
||
<p>For best results, you should first enable full wakelock reporting to allow
|
||
the Battery Historian tool to monitor uninterrupted over an extended period of
|
||
time:</p>
|
||
<pre>
|
||
$ adb shell dumpsys batterystats --enable full-wake-history
|
||
</pre>
|
||
|
||
<p>You should also reset battery statistics at the beginning of a
|
||
measurement:</p>
|
||
<pre>
|
||
$ adb shell dumpsys batterystats --reset
|
||
</pre>
|
||
|
||
<p>To generate an HTML visualization:</p>
|
||
<pre>
|
||
$ historian.par [-p powerfile] bugreport.txt > out.html
|
||
</pre>
|
||
</dd>
|
||
|
||
<dt><strong>On-device power management</strong></dt>
|
||
<dd>
|
||
<p>You can use the {@code android.os.BatteryManager} API to obtain power
|
||
consumption information based on the battery fuel gauge included in Android
|
||
phones and tablets. This is useful in cases when it is not convenient to
|
||
connect external measurement equipment to the Android device.</p>
|
||
<p>To retrieve the battery properties, call {@code BatteryManager.getIntProperty()}
|
||
or {@code BatteryManager.getLongProperty()}. The properties available, the
|
||
exact resolution of the values of each, and other characteristics such as
|
||
update frequency depend on the particular device being tested.</p>
|
||
|
||
<p>The following properties can be inspected on all Android devices:</p>
|
||
|
||
<table>
|
||
<tr>
|
||
<th>Property</th>
|
||
<th>Description</th>
|
||
</tr>
|
||
<tr>
|
||
<td>{@code BatteryManager.BATTERY_PROPERTY_CHARGE_COUNTER}</td>
|
||
<td>Remaining battery capacity in microampere-hours.</td>
|
||
</tr>
|
||
<tr>
|
||
<td>{@code BatteryManager.BATTERY_PROPERTY_CURRENT_NOW}</td>
|
||
<td>Instantaneous battery current in microamperes.</td>
|
||
</tr>
|
||
<tr>
|
||
<td>{@code BatteryManager.BATTERY_PROPERTY_CURRENT_AVERAGE}</td>
|
||
<td>Average battery current in microamperes</td>
|
||
</tr>
|
||
<tr>
|
||
<td>{@code BatteryManager.BATTERY_PROPERTY_CAPACITY}</td>
|
||
<td>Remaining battery capacity as an integer percentage.</td>
|
||
</tr>
|
||
<tr>
|
||
<td>{@code BatteryManager.BATTERY_PROPERTY_ENERGY_COUNTER}</td>
|
||
<td>Remaining energy in nanowatt-hours.</td>
|
||
</tr>
|
||
</table>
|
||
<dd>
|
||
</dl>
|
||
|
||
<h2 id="Enterprise">Enterprise</h2>
|
||
<h3 id="ManagedProvisioning">Managed provisioning</h3>
|
||
|
||
<p>The L Developer Preview provides new functionality for running apps within
|
||
an enterprise environment:</p>
|
||
<ul>
|
||
<li><strong>Create managed user profiles</strong>. A device administrator can
|
||
initiate a managed provisioning process to enroll a user device with an
|
||
existing personal account into a co-present but separate managed profile that
|
||
the administrator controls.
|
||
<li><strong>Set device owner scope</strong>. Device administrators can also
|
||
apply managed provisioning to configure a device that has no previous user
|
||
accounts installed, so that they have full control over the device.
|
||
</ul>
|
||
|
||
<p>To start the manged provisioning process, send
|
||
{@code ACTION_PROVISION_MANAGED_PROFILE} in an {@link android.content.Intent}. A
|
||
user may be associated with more than one managed profile. To get a list of the
|
||
managed profiles associated with the user, call
|
||
{@code android.os.UserManager.getUserProfiles()}.</p>
|
||
|
||
<p>Once a managed profile is created for a user, apps that are managed by the
|
||
device administrator will appear alongside non-managed apps in the user’s
|
||
Launcher, Recent apps screen, and notifications. A device policy management app
|
||
can make the managed apps visually prominent by appending a “work” badge to the
|
||
icon drawable with {@code android.os.UserManager.getBadgeDrawableForUser()}.</p>
|
||
|
||
<p>If you are developing a Launcher app, you can use the new {@code android.content.pm.LauncherApps} class to get a list of launchable activities for the current user
|
||
and any associated managed profiles.</p>
|
||
|
||
<h2 id="Printing">Printing Framework</h2>
|
||
|
||
<h3 id="PDFRender">Render PDF as bitmap</h3>
|
||
<p>You can now render PDF document pages into bitmap images for printing by
|
||
using the new {@code android.graphics.pdf.PdfRenderer} class. You must specify a
|
||
{@code ParcelFileDescriptor} that is seekable (that is, the file can be randomly
|
||
accessed) on which the system writes the the printable content. Your app can
|
||
obtain a page for rendering with {@code openPage()}, then call {@code render()}
|
||
to turn the opened {@code PdfRenderer.Page} into a bitmap. You can also set
|
||
additional parameters if you only wan to convert a portion of the document into
|
||
a bitmap image (for example, to implement <a href="http://en.wikipedia.org/wiki/Tiled_rendering">tile rendering</a> in order to zoom in on the document).</p>
|
||
|
||
<h2 id="TestingA11y">Testing & Accessibility </h2>
|
||
|
||
<h3 id="Testing A11yImprovements">Testing and accessibility improvements</h3>
|
||
<p>The L Developer Preview adds the following support for testing and
|
||
accessibility:</p>
|
||
|
||
<ul>
|
||
<li>You can use the new {@code android.app.UiAutomation.getWindowAnimationFrameStats()}
|
||
and {@code android.app.UiAutomation.getWindowContentFrameStats()} methods to
|
||
capture frame statistics for window animations and content. This lets you
|
||
write instrumentation tests to evaluate if the app under test is rendering
|
||
frames at a sufficient refresh frequency to provide a smooth user experience.
|
||
<li>You can execute shell commands from your instrumentation test with the new
|
||
{@code android.app.UiAutomation.executeShellCommand()}. The command execution
|
||
is similar to running 'adb shell' from a host connected to the device. This
|
||
allows you to use shell based tools such as {@code dumpsys}, {@code am},
|
||
{@code content}, and {@code pm}.
|
||
<li>Accessibility services and test tools that use the accessibility APIs
|
||
(such as <a href="{@docRoot}tools/help/uiautomator/index.html">UiAutomator</a>)
|
||
can now retrieve detailed information about the properties of windows on the
|
||
screen that sighted users can interact with. To retrieve a list of
|
||
{@code android.view.accessibility.AccessibilityWindowInfo} representing the
|
||
windows information, call the new
|
||
{@code android.accessibilityservice.AccessibilityService.getWindows()} method.
|
||
<li>You can use the new {@code android.view.accessibility.AccessibilityNodeInfo.AccessibilityAction} to define standard or customized
|
||
actions to perform on an {@code android.view.accessibility.AccessibilityNodeInfo}.
|
||
The new {@code AccessibilityAction} class replaces the actions-related APIs
|
||
previously found in {@code AccessibilityNodeInfo}.
|
||
</ul>
|
||
|
||
<h2 id="manifest">Manifest Declarations</h2>
|
||
|
||
<h3 id="ManifestFeatures">Declarable required features</h3>
|
||
<p>The following values are now supported in the <a href="{@docRoot}guide/topics/manifest/uses-feature-element.html">{@code <uses-feature>}</a> element so you
|
||
can ensure that your app is installed only on devices that provide the features
|
||
your app needs.</p>
|
||
|
||
<ul>
|
||
<li>{@code FEATURE_LEANBACK}. Declares that your app must be installed only on devices that support the <a href="{@docRoot}tv}">Android TV</a> user interface. Example:
|
||
<pre>
|
||
<uses-feature android:name="android.software.leanback"
|
||
android:required="true" />
|
||
</pre>
|
||
|
||
<li>{@code FEATURE_MANAGEDPROFILES}. Declares that your app must only be installed on devices that support managed profiles for enterprise users. Example:
|
||
<pre>
|
||
<uses-feature android:name="android.software.managedprofiles"
|
||
android:required="true" />
|
||
</pre>
|
||
<li>{@code FEATURE_WEBVIEW}. Declares that your app must only be installed on devices that fully implement the android.webkit.* APIs. Example:
|
||
<pre>
|
||
<uses-feature android:name="android.software.webview"
|
||
android:required="true" />
|
||
</pre>
|
||
</ul>
|
||
|
||
<h3 id="ManifestPermissions">User permissions</h3>
|
||
<p>The following values are now supported in the <a href="{@docRoot}guide/topics/manifest/uses-permission-element.html">{@code <uses-permission>}</a> to declare the
|
||
permissions your app requires in order to access certain APIs.
|
||
|
||
<ul>
|
||
<li>{@code SIM_COMMUNICATION}. Required to communicate with a SIM card using
|
||
logical channels.
|
||
</ul>
|