| page.title=L Developer Preview APIs |
| excludeFromSuggestions=true |
| sdk.platform.apiLevel=20 |
| @jd:body |
| |
| |
| <div id="qv-wrapper"> |
| <div id="qv"> |
| |
| <h2>In this document |
| <a href="#" onclick="hideNestedItems('#toc44',this);return false;" class="header-toggle"> |
| <span class="more">show more</span> |
| <span class="less" style="display:none">show less</span></a></h2> |
| |
| <ol id="toc44" class="hide-nested"> |
| <li><a href="#Behaviors">Important Behavior Changes</a> |
| <ol> |
| <li><a href="#BehaviorNotifications">If your app implements notifications...</a></li> |
| <li><a href="#BehaviorFullscreen">If your app uses fullScreenIntent...</a></li> |
| <li><a href="#BehaviorGetRecentTasks">If your app uses ActivityManager.getRecentTasks()...</a></li> |
| </ol> |
| </li> |
| <li><a href="#UI">User Interface</a> |
| <ol> |
| <li><a href="#MaterialDesign">Material design support</a></li> |
| <li><a href="#LockscreenNotifications">Lockscreen notifications</a></li> |
| <li><a href="#NotificationsMetadata">Notifications metadata</a></li> |
| <li><a href="#Recents">Concurrent documents and activities in Recents screen</a></li> |
| <li><a href="#WebView">WebView updates</a></li> |
| </ol> |
| </li> |
| <li><a href="#UserInput">User Input</a> |
| <ol> |
| <li><a href="#IME">IME bug fixes and improvements</a></li> |
| </ol> |
| </li> |
| <li><a href="#Animations">Animation & Graphics</a> |
| <ol> |
| <li><a href="#OpenGLES-3-1">Support for OpenGL ES 3.1</a></li> |
| </ol> |
| </li> |
| <li><a href="#Multimedia">Multimedia</a> |
| <ol> |
| <li><a href="#Camera-v2">Camera V2</a></li> |
| <li><a href="#AudioPlayback">Audio playback</a></li> |
| <li><a href="#MediaPlaybackControl">Media playback control</a></li> |
| </ol> |
| </li> |
| <li><a href="#Storage">Storage</a> |
| <ol> |
| <li><a href="#DirectorySelection">Directory selection</a></li> |
| </ol> |
| </li> |
| <li><a href="#Wireless">Wireless and Connectivity</a> |
| <ol> |
| <li><a href="#Multinetwork">Dynamic network selection and seamless handoff</a></li> |
| <li><a href="#BluetoothBroadcasting">Bluetooth broadcasting</a></li> |
| <li><a href="#NFCEnhancements">NFC enhancements for payments</a></li> |
| </ol> |
| </li> |
| <li><a href="#Power">Power Efficiency</a> |
| <ol> |
| <li><a href="#JobScheduler">Scheduling Jobs</a></li> |
| <li><a href="#PowerMeasurementTools">Developer tools and APIs for power measurement</a> |
| </ol> |
| </li> |
| <li><a href="#Enterprise">Enterprise</a> |
| <ol> |
| <li><a href="#ManagedProvisioning">Managed provisioning</a></li> |
| </ol> |
| </li> |
| <li><a href="#Printing">Printing Framework</a> |
| <ol> |
| <li><a href="#PDFRender">PDF rendering</a></li> |
| </ol> |
| </li> |
| <li><a href="#TestingA11y">Testing & Accessibility</a> |
| <ol> |
| <li><a href="#TestingA11yImprovements">Testing and accessibility improvements</a></li> |
| </ol> |
| </li> |
| <li><a href="#Manifest">Manifest Declarations</a> |
| <ol> |
| <li><a href="#ManifestFeatures">Declarable required features</a></li> |
| <li><a href="#ManifestPermissions">User permissions</a></li> |
| </ol> |
| </li> |
| </ol> |
| |
| <h2>See also</h2> |
| <ol> |
| <li><a href="{@docRoot}sdk/api_diff/20/changes.html">API |
| Differences Report »</a> </li> |
| </ol> |
| |
| </div> |
| </div> |
| |
| <p>L is an upcoming release for the Android platform |
| that offers new features for users and app developers. This document provides |
| an introduction to the most notable new APIs.</p> |
| |
| <p>L is currently available as a <strong>developer preview</strong> intended |
| for early adopters and testers. If you are interested in influencing the |
| direction of the Android framework, |
| <a href="{@docRoot}preview/setup-sdk.html">give the L Developer Preview a |
| try</a> and send us your feedback!</p> |
| |
| <p class="caution"><strong>Caution:</strong>You should not publish apps |
| using L Developer Preview to the Google Play store.</p> |
| |
| <h2 id="Behaviors">Important Behavior Changes</h2> |
| |
| <p>If you have previously published an app for Android, be aware that your app |
| might be affected by changes in L.</p> |
| |
| <h3 id="BehaviorNotifications">If your app implements notifications...</h3> |
| |
| <p>Notifications will be drawn with dark text atop white (or very light) |
| backgrounds to match the new material design widgets. Make sure that all your |
| notifications look right with the new color scheme. You should remove or update |
| assets and text styles that involve color. The system will automatically invert |
| action icons in notifications. Use |
| {@code android.app.Notification.Builder.setColor()} to set an accent color |
| in a circle behind your {@code Notification.icon} image.</p> |
| |
| <p>The system will ignore all non-alpha channels in action icons and the main |
| notification icon, so you should assume that these icons will be alpha-only. |
| </p> |
| |
| <p>If you are currently adding sounds and vibrations to your notifications by |
| using the {@link android.media.Ringtone}, {@link android.media.MediaPlayer}, |
| or {@link android.os.Vibrator} classes, make sure to remove this code so that |
| the system can present notifications correctly in Do not disturb mode. You |
| should use the {@link android.app.Notification.Builder} methods instead to add |
| sounds and vibration. |
| </p> |
| |
| <h3 id="BehaviorMediaControl">If your app uses RemoteControlClient...</h3> |
| |
| <p>Lockscreens in L will not show transport controls for your |
| {@link android.media.RemoteControlClient}. Instead, your app can provide |
| media playback control from the lockscreen through a media notification. This |
| gives your app more control over the presentation of media buttons, while |
| providing a consistent experience for users across the lockscreen and |
| unlocked device.</p> |
| |
| <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 |
| with a PIN, pattern, or password.</p> |
| |
| <h3 id="BehaviorFullscreen">If your app uses fullScreenIntent...</h3> |
| |
| <p>Notifications now appear in a small floating window if all these conditions |
| are met: the user’s activity is in fullscreen mode, the screen is on, and the |
| device is unlocked. If your app implements fullscreen activities, make sure that |
| these heads-up notifications are presented correctly.</p> |
| |
| <h3 id="BehaviorGetRecentTasks">If your app uses ActivityManager.getRecentTasks()...</h3> |
| |
| <p>With the introduction of the new document tasks feature in L (see below), |
| the {@code android.app.ActivityManager.getRecentTasks()} method is now |
| deprecated to improve user privacy. For backwards |
| compatibility, it will still return a small subset of its data including the |
| calling application’s own tasks and possibly some other non-sensitive tasks |
| such as home. If your app is using this method to retrieve its own tasks, |
| use {@code android.app.ActivityManager.getAppTasks()} instead to retrieve that |
| information.</p> |
| |
| <h2 id="UI">User Interface</h2> |
| |
| <h3 id="MaterialDesign">Material design support</h3> |
| |
| <p>The L Developer Preview adds support for the material design style. You can create |
| material design apps that are visually dynamic and have UI element transitions |
| which feel natural and delightful to users. This support includes:</p> |
| <ul> |
| <li>The Material theme</li> |
| <li>View shadows</li> |
| <li>The {@code RecyclerView} widget</li> |
| <li>Drawable animation and styling effects</li> |
| <li>Material design animation and activity transition effects</li> |
| <li>Animators for view properties based on the state of a view</li> |
| <li>Customizable UI widgets and app bars with color palettes that you control</li> |
| </ul> |
| <p>To learn more about adding material design functionality to your app, see |
| <a href="{@docRoot}preview/material/index.html">Material design on Android</a>.</p> |
| |
| <h3 id="LockscreenNotifications">Lockscreen notifications</h3> |
| <p>Lockscreens in the L Developer Preview have the ability to present notifications. |
| Users can choose via <em>Settings</em> whether to allow sensitive notification |
| content to be shown over a secure lockscreen.</p> |
| |
| <p>Your app can control the level of detail visible when its notifications are |
| displayed over the secure lockscreen. To control the visibility level, call |
| {@code android.app.Notification.Builder.setVisibility()} and specify one of these |
| values:</p> |
| <ul> |
| <li>{@code VISIBILITY_PRIVATE}. Shows basic information, such as the |
| notification’s icon, but hides the notification’s full content. If you want to |
| provide a redacted public version of your notification for the system to display |
| on a secure lockscreen, set the public notification object in the <code>publicVersion</code> |
| field.</li> |
| <li>{@code VISIBILITY_PUBLIC}. Shows the notification’s full content. This is |
| the system default if visibility is left unspecified.</li> |
| <li>{@code VISIBILITY_SECRET}. Shows only the most minimal information, |
| excluding even the notification’s icon.</li> |
| </ul> |
| |
| <h3 id="NotificationsMetadata">Notifications metadata</h3> |
| <p>The L Developer Preview uses metadata associated with your app notifications |
| to more intelligently sort your notifications. The metadata you set also |
| controls how the system presents your app notifications when the user is in <em>Do |
| not disturb</em> mode. When constructing your notification, you can call the |
| following methods in {@code android.app.Notification.Builder}:</p> |
| |
| <ul> |
| <li>{@code setCategory()}. Allows the system to handle your app notifications |
| in <em>Do not disturb mode</em> (for example, if your notification represents an |
| incoming call, instant message, or alarm).</li> |
| <li>{@code setPriority()}. Notifications with the priority field set to |
| {@code PRIORITY_MAX} or {@code PRIORITY_HIGH} will appear in a small floating |
| window if the notification also has sound or vibration.</li> |
| <li>{@code addPerson()}. Allows you to add a list of people to a notification. |
| Your app can use this to signal to the system that it should group together |
| notifications from the specified people, or rank notifications from these |
| people as being more important.</li> |
| </ul> |
| |
| <h3 id="Recents">Concurrent documents and activities in the Recents screen</h3> |
| |
| <p>In previous releases, the |
| <a href="{@docRoot}design/get-started/ui-overview.html">Recents screen</a> |
| could only display a single task for each app that the user interacted with |
| most recently. The L Developer Preview allows your app to open additional tasks |
| for concurrent activities or documents. This feature facilitates multitasking |
| by letting users quickly switch between individual activities and documents |
| from the Recents screen. Examples of such concurrent tasks might include web |
| pages in a browser app, documents in a productivity app, concurrent matches in |
| a game, or chats in a messaging app. Your app can manage its tasks |
| through the {@code android.app.ActivityManager.AppTask} class.</p> |
| |
| <p>To insert a logical break so that the system treats your activity as a new |
| document, use {@code android.content.Intent.FLAG_ACTIVITY_NEW_DOCUMENT} when |
| launching the activity with {@link android.app.Activity#startActivity(android.content.Intent) startActivity()}. You can also get this behavior by declaring the |
| <a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a> |
| attribute {@code documentLaunchMode="intoExisting"} or {@code ="always"} in your |
| manifest.</p> |
| |
| <p>You can also mark that a task should be removed from the Recents screen |
| when all its activities are closed by using {@code android.content.Intent.FLAG_ACTIVITY_AUTO_REMOVE_FROM_RECENTS} when starting the root activity for |
| the task. You can also set this behavior for an activity by declaring the |
| <a href="{@docRoot}guide/topics/manifest/activity-element.html"><activity></a> |
| attribute {@code autoRemoveFromRecents=“true”} in your manifest.</p> |
| |
| <p>To avoid cluttering the Recents screen, you can set the maximum number of |
| tasks from your app that can appear in the Recents screen through the |
| <a href="{@docRoot}guide/topics/manifest/application-element.html"><application></a> attribute {@code android:maxRecent}. The current maximum that can be specified |
| is 100 tasks per user.</a></p> |
| |
| <h3 id="WebView">WebView updates</h3> |
| <p>The L Developer Preview updates the {@link android.webkit.WebView} |
| implementation to Chromium M36, bringing security and stability enhancements, |
| as well as bug fixes. The default user-agent string for a |
| {@link android.webkit.WebView} running on the L Developer Preview has |
| been updated to incorporate 36.0.0.0 as the version number.</p> |
| |
| <p>Additionally, this release brings support for the |
| <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 |
| <a href="http://www.webrtc.org/">WebRTC</a> open standards. To learn more about |
| the new features included in this release, see <a href="https://developer.chrome.com/multidevice/webview/overview">WebView for Android</a>.</p> |
| |
| <h2 id="UserInput">User Input</h2> |
| |
| <h3 id="IME">IME bug fixes and improvements</h3> |
| |
| <p>Beginning in the L Developer Preview, users can more easily switch between |
| all input method editors (IME) <a href="{@docRoot}guide/topics/text/creating-input-method.html">supported by the platform</a>. Performing the designated |
| switching action (usually touching a Globe icon on the soft keyboard) will cycle |
| among all such IMEs. This change takes place in |
| {@code android.view.inputmethod.InputMethodManager.shouldOfferSwitchingToNextInputMethod()}.</p> |
| |
| <p>In addition, the framework will now check whether the next IME includes a |
| switching mechanism at all, thus supporting switching to the IME after it. An |
| IME with a switching mechanism will not cycle to an IME without one. This |
| change takes place in |
| {@code android.view.inputmethod.InputMethodManager.switchToNextInputMethod()}. |
| |
| <p>To see an example of how to use the updated IME-switching APIs, refer to the |
| updated soft-keyboard implementation sample in this release.</p> |
| |
| <h2 id="Animations">Animation & Graphics</h2> |
| |
| <h3 id="OpenGLES-3-1">Support for OpenGL ES 3.1</h3> |
| <p>The L Developer Preview adds Java interfaces and native support for OpenGL |
| ES 3.1. Key new functionality provided in OpenGL ES 3.1 includes:</p> |
| |
| <ul> |
| <li>Compute shaders |
| <li>Separate shader objects |
| <li>Indirect draw commands |
| <li>Enhanced texturing functionality |
| <li>Shading language improvements |
| <li>Optional extensions for per-sample shading, advanced blending modes, and more |
| <li>Backward compatibility with OpenGL ES 2.0 and 3.0 |
| </ul> |
| |
| <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 |
| <a href="{@docRoot}guide/topics/manifest/uses-feature-element.html">{@code <uses-feature>}</a> tag and the {@code android:glEsVversion} attribute. For example:</p> |
| |
| <pre> |
| <manifest> |
| <uses-feature android:glEsVersion="0x00030001" /> |
| ... |
| </manifest> |
| </pre> |
| |
| <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> |
| |
| <h2 id="Multimedia">Multimedia</h2> |
| |
| <h3 id="Camera=v2">Camera v2 API</h3> |
| |
| <p>The L Developer Preview introduces the new {@code android.hardware.camera2} |
| 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 |
| need to create a {@code CameraCaptureSession} and specify the |
| {@link android.view.Surface} objects to send the captured images. The {@code CameraCaptureSession} can be configured to take single shots or multiple images |
| in a burst.</p> |
| |
| <p>To be notified when new images are captured, implement the |
| {@code CameraCaptureSession.CaptureListener()} interface and set it in your |
| capture request. Now when the system completes the image capture request, your |
| {@code CameraCaptureSession.CaptureListener()} receives a call to |
| {@code onCaptureCompleted()}, providing you with the image capture metadata in a |
| {@code CaptureResult}.</p> |
| |
| <h3 id="AudioPlayback">Audio playback</h3> |
| <p>This release includes the following changes for |
| {@code android.media.AudioTrack}:</p> |
| <ul> |
| <li>Your app can now supply audio data in floating-point format |
| ({@code android.media.AudioFormat.ENCODING_PCM_FLOAT}). This permits greater |
| dynamic range, more consistent precision, and greater headroom. Floating-point arithmetic is especially useful during intermediate calculations. Playback |
| end-points use integer format for audio data, and with lower bit-depth. In L |
| Developer Preview, portions of the internal pipeline are not yet floating-point. |
| <li>Your app can now supply audio data as a {@code ByteBuffer}, in the same |
| format as provided by {@code MediaCodec}. |
| <li>The {@code WRITE_NON_BLOCKING} option can simplify buffering and |
| multithreading for some apps. |
| </ul> |
| |
| <h3 id="MediaPlaybackControl">Media playback control</h3> |
| <p>You can now build your own media controller app with the new |
| {@code android.media.session.MediaController} class, which provides |
| simplified transport controls APIs that replace those in |
| {@code android.media.RemoteControlClient}. The {@code MediaController} class |
| allows thread-safe control of playback from a non UI process, making it easier |
| to control your media playback service from your app’s user interface. |
| |
| <p>You can also create multiple controllers to send playback commands, |
| media keys, and other events to the same ongoing |
| {@code android.media.session.MediaSession}. When you add a controller, you must |
| call {@code MediaSession.getSessionToken()} to request an access |
| token in order for your app to interact with the session.</p> |
| |
| <p>Send transport commands such as "play", "stop", "skip", and |
| "set rating" by using {@code MediaController.TransportControls}. To handle |
| in-bound media transport commands from controllers attached to the session, you |
| should override the callback methods in |
| {@code MediaSession.TransportControlsCallback}.</p> |
| |
| <p>You can also create rich notifications that allow playback control tied to a |
| media session with the new {@code android.app.Notification.MediaStyle} class.</p> |
| |
| <h2 id="Storage">Storage</h2> |
| |
| <h3 id="DirectorySelection">Directory selection</h3> |
| |
| <p>The L Developer Preview extends the <a href="{@docRoot}guide/topics/providers/document-provider.html">Storage Access Framework</a> to let users |
| select an entire directory, rather than individual files, to give your app |
| read/write access to media files. When a directory is selected, your app also |
| has access to all its child directories and content.</p> |
| |
| <p>To get the absolute paths to directories on external storage devices where |
| applications can store media files, call the |
| {@code android.content.Context.getExternalMediaDirs()} method. No additional |
| permissions are needed by your app to read or write to the returned paths. |
| External storage devices here are those considered by the system to be a |
| permanent part of the device, and includes emulated external storage and |
| physical media slots such as SD cards in battery compartments.</p> |
| |
| <p>If you want to access a document in an existing directory, call the |
| {@code android.provider.DocumentsContract.buildDocumentViaUri()} method and pass |
| in a Uri representing the path to the parent directory and the target document |
| ID. The method returns a new {@link android.net.Uri} with which your app can |
| use to write media content with {@code DocumentsContract.createDocument()}. |
| |
| <h2 id="Wireless">Wireless & Connectivity</h2> |
| |
| <h3 id="Multinetwork">Dynamic network selection and seamless handoff</h3> |
| <p>The L Developer Preview provides new multi-networking APIs for your app to |
| dynamically scan for available networks with specific capabilities, and |
| establish a connection to them. This is useful when your app requires a |
| specialized network, such as an SUPL, MMS, or carrier-billing network, or if |
| you want to send data using a particular type of transport protocol.</p> |
| |
| <p>To select and connect to a network dynamically from your app, first |
| instantiate a {@code android.net.ConnectivityManager}. Next, create a |
| {@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> |