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+page.title=API Overview
+page.keywords=preview,sdk,compatibility
+page.tags=previewresources, androidm
+sdk.platform.apiLevel=22-mnc
+page.image=images/cards/card-api-overview_16-9_2x.png
+@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="#app-linking">App Linking</a></li>
+ <li><a href="#backup">Auto Backup for Apps</a></li>
+ <li><a href="#authentication">Authentication</a>
+ <ol>
+ <li><a href="#fingerprint-authentication">Fingerprint Authentication</a></li>
+ <li><a href="#confirm-credential">Confirm Credential</a></li>
+ </ol>
+ </li>
+ <li><a href="#direct-share">Direct Share</a></li>
+ <li><a href="#voice-interactions">Voice Interactions</a></li>
+ <li><a href="#assist">Assist API</a></li>
+ <li><a href="#notifications">Notifications</a></li>
+ <li><a href="#bluetooth-stylus">Bluetooth Stylus Support</a></li>
+ <li><a href="#ble-scanning">Improved Bluetooth Low Energy Scanning</a></li>
+ <li><a href="#hotspot">Hotspot 2.0 Release 1 Support</a></li>
+ <li><a href="#4K-display">4K Display Mode</a></li>
+ <li><a href="#behavior-themeable-colorstatelists">Themeable ColorStateLists</a></li>
+ <li><a href="#audio">Audio Features</a></li>
+ <li><a href="#video">Video Features</a></li>
+ <li><a href="#camera">Camera Features</a>
+ <ol>
+ <li><a href="#flashlight">Flashlight API</a></li>
+ <li><a href="#reprocessing">Camera Reprocessing</a></li>
+ </ol>
+ </li>
+ <li><a href="#afw">Android for Work Features</a></li>
+</ol>
+
+<h2>API Differences</h2>
+<ol>
+<li><a href="{@docRoot}sdk/api_diff/23/changes.html">API level 22 to 23 (Preview 3) »</a> </li>
+</ol>
+
+</div>
+</div>
+
+<p>The M Developer Preview gives you an advance look at the upcoming release
+for the Android platform, which offers new features for users and app
+developers. This document provides an introduction to the most notable APIs.</p>
+
+<p>
+ The M Developer Preview 3 release includes the <strong>final APIs for Android 6.0 (API level
+ 23)</strong>. If you are preparing an app for use on Android 6.0,
+ <a href="{@docRoot}preview/setup-sdk.html">download the latest SDK</a> and to complete your
+ final updates and release testing. You can review the final APIs in the
+ <a href="{@docRoot}reference/packages.html">API Reference</a> and see the API differences in
+ the <a href="{@docRoot}sdk/api_diff/23/changes.html">Android API Differences Report</a>.
+</p>
+
+</p>
+
+<p class="caution"><strong>Important:</strong>
+ You may now publish apps that target Android 6.0 (API level 23) to the Google Play store.
+</p>
+
+<p class="note"><strong>Note:</strong>
+ If you have been working with previous preview releases and want to see the differences
+ between the final API and previous preview versions, download the additional difference
+ reports included in the <a href="{@docRoot}preview/download.html#docs">preview docs
+ reference</a>.
+</p>
+
+<h3>Important behavior changes</h3>
+
+<p>If you have previously published an app for Android, be aware that your app might be affected
+by changes in the platform.</p>
+
+<p>Please see <a href="behavior-changes.html">Behavior Changes</a> for complete information.</p>
+
+<h2 id="app-linking">App Linking</h2>
+<p>This preview enhances Android’s intent system by providing more powerful app linking.
+This feature allows you to associate an app with a web domain you own. Based on this
+association, the platform can determine the default app to use to handle a particular
+web link and skip prompting users to select an app. To learn how to implement this feature, see
+<a href="{@docRoot}preview/features/app-linking.html">App Linking</a>.
+
+<h2 id="backup">Auto Backup for Apps</h2>
+<p>The system now performs automatic full data backup and restore for apps. For the
+duration of the <a href="{@docRoot}preview/overview.html">M Developer Preview program</a>, all
+apps are backed up, independent of which SDK version they target. After the final M SDK release,
+your app must target M to enable this behavior; you do not need to add any additional code. If users
+delete their Google accounts, their backup data is deleted as well. To learn how this feature
+works and how to configure what to back up on the file system, see
+<a href="{@docRoot}preview/backup/index.html">Auto Backup for Apps</a>.</p>
+
+<h2 id="authentication">Authentication</h2>
+<p>This preview offers new APIs to let you authenticate users by using their fingerprint scans on
+supported devices, and check how recently the user was last authenticated using a device unlocking
+mechanism (such as a lockscreen password). Use these APIs in conjunction with
+the <a href="{@docRoot}training/articles/keystore.html">Android Keystore system</a>.</p>
+
+<h3 id="fingerprint-authentication">Fingerprint Authentication</h3>
+
+<p>To authenticate users via fingerprint scan, get an instance of the new
+{@link android.hardware.fingerprint.FingerprintManager} class and call the
+{@link android.hardware.fingerprint.FingerprintManager#authenticate(android.hardware.fingerprint.FingerprintManager.CryptoObject, android.os.CancellationSignal, int, android.hardware.fingerprint.FingerprintManager.AuthenticationCallback, android.os.Handler) authenticate()}
+method. Your app must be running on a compatible
+device with a fingerprint sensor. You must implement the user interface for the fingerprint
+authentication flow on your app, and use the standard Android fingerprint icon in your UI.
+The Android fingerprint icon ({@code c_fp_40px.png}) is included in the
+<a href="https://github.com/googlesamples/android-FingerprintDialog"
+class="external-link">sample app</a>. If you are developing multiple apps that use fingerprint
+authentication, note that each app must authenticate the user’s fingerprint independently.
+</p>
+
+<p>To use this feature in your app, first add the
+ {@link android.Manifest.permission#USE_FINGERPRINT} permission in your manifest.</p>
+
+<pre>
+<uses-permission
+ android:name="android.permission.USE_FINGERPRINT" />
+</pre>
+<img src="{@docRoot}preview/images/fingerprint-screen.png"
+srcset="{@docRoot}preview/images/fingerprint-screen.png 1x, {@docRoot}preview/images/fingerprint-screen_2x.png 2x"
+style="float:right; margin:0 0 10px 20px" width="282" height="476" />
+
+<p>To see an app implementation of fingerprint authentication, refer to the
+<a href="https://github.com/googlesamples/android-FingerprintDialog" class="external-link">
+ Fingerprint Dialog sample</a>. For a demonstration of how you can use these authentication
+ APIs in conjunction with other Android APIs, see the video
+ <a class="video-shadowbox-button" href="https://www.youtube.com/watch?v=VOn7VrTRlA4">
+ Fingerprint and Payment APIs</a>.</p>
+
+<p>If you are testing this feature, follow these steps:</p>
+<ol>
+<li>Install Android SDK Tools Revision 24.3, if you have not done so.</li>
+<li>Enroll a new fingerprint in the emulator by going to
+<strong>Settings > Security > Fingerprint</strong>, then follow the enrollment instructions.</li>
+<li>Use an emulator to emulate fingerprint touch events with the
+following command. Use the same command to emulate fingerprint touch events on the lockscreen or
+in your app.
+<pre class="no-prettyprint">
+adb -e emu finger touch <finger_id>
+</pre>
+<p>On Windows, you may have to run {@code telnet 127.0.0.1 <emulator-id>} followed by
+ {@code finger touch <finger_id>}.
+</p>
+</li>
+</ol>
+
+<h3 id="confirm-credential">Confirm Credential</h3>
+<p>Your app can authenticate users based on how recently they last unlocked their device. This
+feature frees users from having to remember additional app-specific passwords, and avoids the need
+for you to implement your own authentication user interface. Your app should use this feature in
+conjunction with a public or secret key implementation for user authentication.</p>
+
+<p>To set the timeout duration for which the same key can be re-used after a user is successfully
+authenticated, call the new
+{@link android.security.keystore.KeyGenParameterSpec.Builder#setUserAuthenticationValidityDurationSeconds(int) setUserAuthenticationValidityDurationSeconds()}
+method when you set up a {@link javax.crypto.KeyGenerator} or
+{@link java.security.KeyPairGenerator}.</p>
+
+<p>Avoid showing the re-authentication dialog excessively -- your apps should try using the
+cryptographic object first and if the the timeout expires, use the
+{@link android.app.KeyguardManager#createConfirmDeviceCredentialIntent(java.lang.CharSequence, java.lang.CharSequence) createConfirmDeviceCredentialIntent()}
+method to re-authenticate the user within your app.
+</p>
+
+<p>To see an app implementation of this feature, refer to the
+<a href="https://github.com/googlesamples/android-ConfirmCredential" class="external-link">
+ Confirm Credential sample</a>.</p>
+
+<h2 id="direct-share">Direct Share</h2>
+
+<img src="{@docRoot}preview/images/direct-share-screen.png"
+srcset="{@docRoot}preview/images/direct-share-screen.png 1x, {@docRoot}preview/images/direct-share-screen_2x.png 2x"
+style="float:right; margin:0 0 20px 30px" width="312" height="329" />
+
+<p>This preview provides you with APIs to make sharing intuitive and quick for users. You can now
+define <em>direct share targets</em> that launch a specific activity in your app. These direct share
+targets are exposed to users via the <em>Share</em> menu. This feature allows users to share
+content to targets, such as contacts, within other apps. For example, the direct share target might
+launch an activity in another social network app, which lets the user share content directly to a
+specific friend or community in that app.</p>
+
+<p>To enable direct share targets you must define a class that extends the
+{@link android.service.chooser.ChooserTargetService} class. Declare your
+service in the manifest. Within that declaration, specify the
+{@link android.Manifest.permission#BIND_CHOOSER_TARGET_SERVICE} permission and an
+intent filter using the
+{@link android.service.chooser.ChooserTargetService#SERVICE_INTERFACE SERVICE_INTERFACE} action.</p>
+<p>The following example shows how you might declare the
+{@link android.service.chooser.ChooserTargetService} in your manifest.</p>
+<pre>
+<service android:name=".ChooserTargetService"
+ android:label="@string/service_name"
+ android:permission="android.permission.BIND_CHOOSER_TARGET_SERVICE">
+ <intent-filter>
+ <action android:name="android.service.chooser.ChooserTargetService" />
+ </intent-filter>
+</service>
+</pre>
+
+<p>For each activity that you want to expose to
+{@link android.service.chooser.ChooserTargetService}, add a
+{@code <meta-data>} element with the name
+{@code "android.service.chooser.chooser_target_service"} in your app manifest.
+</p>
+
+<pre>
+<activity android:name=".MyShareActivity”
+ android:label="@string/share_activity_label">
+ <intent-filter>
+ <action android:name="android.intent.action.SEND" />
+ </intent-filter>
+<meta-data
+ android:name="android.service.chooser.chooser_target_service"
+ android:value=".ChooserTargetService" />
+</activity>
+</pre>
+
+<h2 id="voice-interactions">Voice Interactions</h2>
+<p>
+This preview provides a new voice interaction API which, together with
+<a href="https://developers.google.com/voice-actions/" class="external-link">Voice Actions</a>,
+allows you to build conversational voice experiences into your apps. Call the
+{@link android.app.Activity#isVoiceInteraction()} method to determine if a voice action triggered
+your activity. If so, your app can use the
+{@link android.app.VoiceInteractor} class to request a voice confirmation from the user, select
+from a list of options, and more.</p>
+
+<p>Most voice interactions originate from a user voice action. A voice interaction activity can
+also, however, start without user input. For example, another app launched through a voice
+interaction can also send an intent to launch a voice interaction. To determine if your activity
+launched from a user voice query or from another voice interaction app, call the
+{@link android.app.Activity#isVoiceInteractionRoot()} method. If another app launched your
+activity, the method returns {@code false}. Your app may then prompt the user to confirm that
+they intended this action.</p>
+
+<p>To learn more about implementing voice actions, see the
+<a href="https://developers.google.com/voice-actions/interaction/"
+class="external-link">Voice Actions developer site</a>.
+</p>
+
+<h2 id="assist">Assist API</h2>
+<p>
+This preview offers a new way for users to engage with your apps through an assistant. To use this
+feature, the user must enable the assistant to use the current context. Once enabled, the user
+can summon the assistant within any app, by long-pressing on the <strong>Home</strong> button.</p>
+<p>Your app can elect to not share the current context with the assistant by setting the
+{@link android.view.WindowManager.LayoutParams#FLAG_SECURE} flag. In addition to the
+standard set of information that the platform passes to the assistant, your app can share
+additional information by using the new {@link android.app.assist.AssistContent} class.</p>
+
+<p>To provide the assistant with additional context from your app, follow these steps:</p>
+
+<ol>
+<li>Implement the {@link android.app.Application.OnProvideAssistDataListener} interface.</li>
+<li>Register this listener by using
+{@link android.app.Application#registerOnProvideAssistDataListener(android.app.Application.OnProvideAssistDataListener) registerOnProvideAssistDataListener()}.</li>
+<li>In order to provide activity-specific contextual information, override the
+{@link android.app.Activity#onProvideAssistData(android.os.Bundle) onProvideAssistData()}
+callback and, optionally, the new
+{@link android.app.Activity#onProvideAssistContent(android.app.assist.AssistContent) onProvideAssistContent()}
+callback.
+</ol>
+
+<h2 id="notifications">Notifications</h2>
+<p>This preview adds the following API changes for notifications:</p>
+<ul>
+ <li>New {@link android.app.NotificationManager#INTERRUPTION_FILTER_ALARMS} filter level that
+ corresponds to the new <em>Alarms only</em> do not disturb mode.</li>
+ <li>New {@link android.app.Notification#CATEGORY_REMINDER} category value that is used to
+ distinguish user-scheduled reminders from other events
+ ({@link android.app.Notification#CATEGORY_EVENT}) and alarms
+ ({@link android.app.Notification#CATEGORY_ALARM}).</li>
+ <li>New {@link android.graphics.drawable.Icon} class that you can attach to your notifications
+ via the
+ {@link android.app.Notification.Builder#setSmallIcon(android.graphics.drawable.Icon) setSmallIcon()}
+ and {@link android.app.Notification.Builder#setLargeIcon(android.graphics.drawable.Icon) setLargeIcon()}
+ methods. Similarly, the
+ {@link android.app.Notification.Builder#addAction(int, java.lang.CharSequence, android.app.PendingIntent)
+ addAction()} method now accepts an {@link android.graphics.drawable.Icon} object instead of a
+ drawable resource ID.</li>
+ <li>New {@link android.app.NotificationManager#getActiveNotifications()} method that allows your
+ apps to find out which of their notifications are currently alive. To see an app implementation
+ that uses this feature, see the <a href="https://github.com/googlesamples/android-ActiveNotifications"
+ class="external-link">Active Notifications sample</a>.</li>
+</ul>
+
+<h2 id="bluetooth-stylus">Bluetooth Stylus Support</h2>
+<p>This preview provides improved support for user input using a Bluetooth stylus. Users can pair
+and connect a compatible Bluetooth stylus with their phone or tablet. While connected, position
+information from the touch screen is fused with pressure and button information from the stylus to
+provide a greater range of expression than with the touch screen alone. Your app can listen for
+stylus button presses and perform secondary actions, by registering
+{@link android.view.View.OnContextClickListener} and
+{@link android.view.GestureDetector.OnContextClickListener} objects in your activity.</p>
+
+<p>Use the {@link android.view.MotionEvent} methods and constants to detect stylus button
+interactions:</p>
+<ul>
+<li>If the user touches a stylus with a button on the screen of your app, the
+{@link android.view.MotionEvent#getToolType(int) getTooltype()} method returns
+{@link android.view.MotionEvent#TOOL_TYPE_STYLUS}.</li>
+<li>For apps targeting M Preview, the
+{@link android.view.MotionEvent#getButtonState() getButtonState()}
+method returns {@link android.view.MotionEvent#BUTTON_STYLUS_PRIMARY} when the user
+presses the primary stylus button. If the stylus has a second button, the same method returns
+{@link android.view.MotionEvent#BUTTON_STYLUS_SECONDARY} when the user presses it. If the user presses
+both buttons simultaneously, the method returns both values OR'ed together
+({@link android.view.MotionEvent#BUTTON_STYLUS_PRIMARY}|{@link android.view.MotionEvent#BUTTON_STYLUS_SECONDARY}).</li>
+<li>
+For apps targeting a lower platform version, the
+{@link android.view.MotionEvent#getButtonState() getButtonState()} method returns
+{@link android.view.MotionEvent#BUTTON_SECONDARY} (for primary stylus button press),
+{@link android.view.MotionEvent#BUTTON_TERTIARY} (for secondary stylus button press), or both.
+</li>
+</ul>
+
+<h2 id="ble-scanning">Improved Bluetooth Low Energy Scanning</h2>
+<p>
+If your app performs performs Bluetooth Low Energy scans, use the new
+{@link android.bluetooth.le.ScanSettings.Builder#setCallbackType(int) setCallbackType()}
+method to specify that you want the system to notify callbacks when it first finds, or sees after a
+long time, an advertisement packet matching the set {@link android.bluetooth.le.ScanFilter}. This
+approach to scanning is more power-efficient than what’s provided in the previous platform version.
+</p>
+
+<h2 id="hotspot">Hotspot 2.0 Release 1 Support</h2>
+<p>
+This preview adds support for the Hotspot 2.0 Release 1 spec on Nexus 6 and Nexus 9 devices. To
+provision Hotspot 2.0 credentials in your app, use the new methods of the
+{@link android.net.wifi.WifiEnterpriseConfig} class, such as
+{@link android.net.wifi.WifiEnterpriseConfig#setPlmn(java.lang.String) setPlmn()} and
+{@link android.net.wifi.WifiEnterpriseConfig#setRealm(java.lang.String) setRealm()}. In the
+{@link android.net.wifi.WifiConfiguration} object, you can set the
+{@link android.net.wifi.WifiConfiguration#FQDN} and the
+{@link android.net.wifi.WifiConfiguration#providerFriendlyName} fields.
+The new {@link android.net.wifi.ScanResult#isPasspointNetwork()} method indicates if a detected
+network represents a Hotspot 2.0 access point.
+</p>
+
+<h2 id="4K-display">4K Display Mode</h2>
+<p>The platform now allows apps to request that the display resolution be upgraded to 4K rendering
+on compatible hardware. To query the current physical resolution, use the new
+{@link android.view.Display.Mode} APIs. If the UI is drawn at a lower logical resolution and is
+upscaled to a larger physical resolution, be aware that the physical resolution the
+{@link android.view.Display.Mode#getPhysicalWidth()} method returns may differ from the logical
+resolution reported by {@link android.view.Display#getSize(android.graphics.Point) getSize()}.</p>
+
+<p>You can request the system to change the physical resolution in your app as it runs, by setting
+the {@link android.view.WindowManager.LayoutParams#preferredDisplayModeId} property of your app’s
+window. This feature is useful if you want to switch to 4K display resolution. While in 4K display
+mode, the UI continues to be rendered at the original resolution (such as 1080p) and is upscaled to
+4K, but {@link android.view.SurfaceView} objects may show content at the native resolution.</p>
+
+<h2 id="behavior-themeable-colorstatelists">Themeable ColorStateLists</h2>
+<p>Theme attributes are now supported in
+{@link android.content.res.ColorStateList} for devices running the M Preview. The
+{@link android.content.res.Resources#getColorStateList(int) getColorStateList()} and
+{@link android.content.res.Resources#getColor(int) getColor()} methods have been deprecated. If
+you are calling these APIs, call the new
+{@link android.content.Context#getColorStateList(int) getColorStateList()} or
+{@link android.content.Context#getColor(int) getColor()} methods instead. These methods are also
+available in the v4 appcompat library via {@link android.support.v4.content.ContextCompat}.</p>
+
+<h2 id="audio">Audio Features</h2>
+
+<p>This preview adds enhancements to audio processing on Android, including: </p>
+<ul>
+ <li>Support for the <a href="http://en.wikipedia.org/wiki/MIDI" class="external-link">MIDI</a>
+protocol, with the new {@link android.media.midi} APIs. Use these APIs to send and receive MIDI
+events.</li>
+ <li>New {@link android.media.AudioRecord.Builder} and {@link android.media.AudioTrack.Builder}
+classes to create digital audio capture and playback objects respectively, and configure audio
+source and sink properties to override the system defaults.</li>
+ <li>API hooks for associating audio and input devices. This is particularly useful if your app
+allows users to start a voice search from a game controller or remote control connected to Android
+TV. The system invokes the new
+{@link android.app.Activity#onSearchRequested(android.view.SearchEvent) onSearchRequested()}
+callback when the user starts a search. To determine if the user's input device has a built-in
+microphone, retrieve the {@link android.view.InputDevice} object from that callback, then call the
+new {@link android.view.InputDevice#hasMicrophone()} method.</li>
+ <li>New {@link android.media.AudioManager#getDevices(int) getDevices()} method which lets you
+retrieve a list of all audio devices currently connected to the system. You can also register an
+{@link android.media.AudioDeviceCallback} object if you want the system to notify your app
+when an audio device connects or disconnects.</li>
+</ul>
+
+<h2 id="video">Video Features</h2>
+<p>This preview adds new capabilities to the video processing APIs, including:</p>
+<ul>
+<li>New {@link android.media.MediaSync} class which helps applications to synchronously render
+audio and video streams. The audio buffers are submitted in non-blocking fashion and are
+returned via a callback. It also supports dynamic playback rate.
+</li>
+<li>New {@link android.media.MediaDrm#EVENT_SESSION_RECLAIMED} event, which indicates that a
+session opened by the app has been reclaimed by the resource manager. If your app uses DRM sessions,
+you should handle this event and make sure not to use a reclaimed session.
+</li>
+<li>New {@link android.media.MediaCodec.CodecException#ERROR_RECLAIMED} error code, which indicates
+that the resource manager reclaimed the media resource used by the codec. With this exception, the
+codec must be released, as it has moved to terminal state.
+</li>
+<li>New {@link android.media.MediaCodecInfo.CodecCapabilities#getMaxSupportedInstances()
+getMaxSupportedInstances()} interface to get a hint for the max number of the supported
+concurrent codec instances.
+</li>
+<li>New {@link android.media.MediaPlayer#setPlaybackParams(android.media.PlaybackParams)
+setPlaybackParams()} method to set the media playback rate for fast or
+slow motion playback. It also stretches or speeds up the audio playback automatically in
+conjunction with the video.</li>
+</ul>
+
+<h2 id="camera">Camera Features</h2>
+<p>This preview includes the following new APIs for accessing the camera’s flashlight and for
+camera reprocessing of images:</p>
+
+<h3 id="flashlight">Flashlight API</h3>
+<p>If a camera device has a flash unit, you can call the
+{@link android.hardware.camera2.CameraManager#setTorchMode(java.lang.String, boolean) setTorchMode()}
+method to switch the flash unit’s torch mode on or off without opening the camera device. The app
+does not have exclusive ownership of the flash unit or the camera device. The torch mode is turned
+off and becomes unavailable whenever the camera device becomes unavailable, or when other camera
+resources keeping the torch on become unavailable. Other apps can also call
+{@link android.hardware.camera2.CameraManager#setTorchMode(java.lang.String, boolean) setTorchMode()}
+to turn off the torch mode. When the last app that turned on the torch mode is closed, the torch
+mode is turned off.</p>
+
+<p>You can register a callback to be notified about torch mode status by calling the
+{@link android.hardware.camera2.CameraManager#registerTorchCallback(android.hardware.camera2.CameraManager.TorchCallback, android.os.Handler) registerTorchCallback()}
+method. The first time the callback is registered, it is immediately called with the torch mode
+status of all currently known camera devices with a flash unit. If the torch mode is turned on or
+off successfully, the
+{@link android.hardware.camera2.CameraManager.TorchCallback#onTorchModeChanged(java.lang.String, boolean) onTorchModeChanged()}
+method is invoked.</p>
+
+<h3 id="reprocessing">Reprocessing API</h3>
+<p>The {@link android.hardware.camera2 Camera2} API is extended to support YUV and private
+opaque format image reprocessing. To determine if these reprocessing capabilities are available,
+call {@link android.hardware.camera2.CameraManager#getCameraCharacteristics(java.lang.String)
+getCameraCharacteristics()} and check for the
+{@link android.hardware.camera2.CameraCharacteristics#REPROCESS_MAX_CAPTURE_STALL} key. If a
+device supports reprocessing, you can create a reprocessable camera capture session by calling
+<a href="/reference/android/hardware/camera2/CameraDevice.html#createReprocessableCaptureSession(android.hardware.camera2.params.InputConfiguration, java.util.List<android.view.Surface>, android.hardware.camera2.CameraCaptureSession.StateCallback, android.os.Handler)"><code>createReprocessableCaptureSession()</code></a>,
+and create requests for input buffer reprocessing.</p>
+
+<p>Use the {@link android.media.ImageWriter} class to connect the input buffer flow to the camera
+reprocessing input. To get an empty buffer, follow this programming model:</p>
+
+<ol>
+<li>Call the {@link android.media.ImageWriter#dequeueInputImage()} method.</li>
+<li>Fill the data into the input buffer.</li>
+<li>Send the buffer to the camera by calling the
+{@link android.media.ImageWriter#queueInputImage(android.media.Image) queueInputImage()} method.</li>
+</ol>
+
+<p>If you are using a {@link android.media.ImageWriter} object together with an
+{@link android.graphics.ImageFormat#PRIVATE} image, your app cannot access the image
+data directly. Instead, pass the {@link android.graphics.ImageFormat#PRIVATE} image directly to the
+{@link android.media.ImageWriter} by calling the
+{@link android.media.ImageWriter#queueInputImage(android.media.Image) queueInputImage()} method
+without any buffer copy.</p>
+
+<p>The {@link android.media.ImageReader} class now supports
+{@link android.graphics.ImageFormat#PRIVATE} format image streams. This support allows your app to
+maintain a circular image queue of {@link android.media.ImageReader} output images, select one or
+more images, and send them to the {@link android.media.ImageWriter} for camera reprocessing.</p>
+
+<h2 id="afw">Android for Work Features</h2>
+<p>This preview includes the following new APIs for Android for Work:</p>
+<ul>
+ <li><strong>Enhanced controls for Corporate-Owned, Single-Use devices:</strong> The Device Owner
+can now control the following settings to improve management of
+Corporate-Owned, Single-Use (COSU) devices:
+ <ul>
+ <li>Disable or re-enable the keyguard with the
+{@link android.app.admin.DevicePolicyManager#setKeyguardDisabled(android.content.ComponentName, boolean)
+setKeyguardDisabled()} method.</li>
+ <li>Disable or re-enable the status bar (including quick settings, notifications, and the
+navigation swipe-up gesture that launches Google Now) with the
+{@link android.app.admin.DevicePolicyManager#setStatusBarDisabled(android.content.ComponentName, boolean) setStatusBarDisabled()}
+method.</li>
+ <li>Disable or re-enable safe boot with the {@link android.os.UserManager} constant
+{@link android.os.UserManager#DISALLOW_SAFE_BOOT}.</li>
+ <li>Prevent the screen from turning off while plugged in with the
+ {@link android.provider.Settings.Global#STAY_ON_WHILE_PLUGGED_IN} constant.</li>
+ </ul>
+ </li>
+ <li><strong>Silent install and uninstall of apps by Device Owner:</strong> A Device Owner can now
+silently install and uninstall applications using the {@link android.content.pm.PackageInstaller}
+APIs, independent of Google Play for Work. You can now provision devices through a Device Owner that
+fetches and installs apps without user interaction. This feature is useful for enabling one-touch
+provisioning of kiosks or other such devices without activating a Google account.</li>
+<li><strong>Silent enterprise certificate access: </strong> When an app calls
+{@link android.security.KeyChain#choosePrivateKeyAlias(android.app.Activity,android.security.KeyChainAliasCallback,java.lang.String[],java.security.Principal[],java.lang.String,int,java.lang.String) choosePrivateKeyAlias()},
+prior to the user being prompted to select a certificate, the Profile or Device Owner can now call
+the {@link android.app.admin.DeviceAdminReceiver#onChoosePrivateKeyAlias(android.content.Context, android.content.Intent, int, android.net.Uri, java.lang.String) onChoosePrivateKeyAlias()}
+method to provide the alias silently to the requesting application. This feature lets you grant
+managed apps access to certificates without user interaction.</li>
+<li><strong>Auto-acceptance of system updates.</strong> By setting a system update policy with
+{@link android.app.admin.DevicePolicyManager#setSystemUpdatePolicy(android.content.ComponentName, android.app.admin.SystemUpdatePolicy) setSystemUpdatePolicy()},
+a Device Owner can now auto-accept a system
+update, for instance in the case of a kiosk device, or postpone the update and prevent it being
+taken by the user for up to 30 days. Furthermore, an administrator can set a daily time window in
+which an update must be taken, for example during the hours when a kiosk device is not in use. When
+a system update is available, the system checks if the Work Policy Controller app has set a system
+update policy, and behaves accordingly.
+</li>
+<li>
+<strong>Delegated certificate installation:</strong> A Profile or Device Owner can now grant a
+third-party app the ability to call these {@link android.app.admin.DevicePolicyManager} certificate
+management APIs:
+<ul>
+ <li>{@link android.app.admin.DevicePolicyManager#getInstalledCaCerts(android.content.ComponentName)
+getInstalledCaCerts()}</li>
+ <li>{@link android.app.admin.DevicePolicyManager#hasCaCertInstalled(android.content.ComponentName,byte[])
+hasCaCertInstalled()}</li>
+ <li>{@link android.app.admin.DevicePolicyManager#installCaCert(android.content.ComponentName,byte[])
+installCaCert()}</li>
+ <li>{@link android.app.admin.DevicePolicyManager#uninstallCaCert(android.content.ComponentName,byte[])
+uninstallCaCert()}</li>
+ <li>{@link android.app.admin.DevicePolicyManager#uninstallAllUserCaCerts(android.content.ComponentName)
+uninstallAllUserCaCerts()}</li>
+ <li>{@link android.app.admin.DevicePolicyManager#installKeyPair(android.content.ComponentName,java.security.PrivateKey,java.security.cert.Certificate,java.lang.String)
+installKeyPair()}</li>
+</ul>
+</li>
+<img src="{@docRoot}preview/images/work-profile-screen.png"
+srcset="{@docRoot}preview/images/work-profile-screen.png 1x, {@docRoot}preview/images/work-profile-screen_2x.png 2x"
+style="float:right; margin:0 0 10px 20px" width="282" height="476" />
+<li><strong>Data usage tracking.</strong> A Profile or Device Owner can now query for the
+data usage statistics visible in <strong>Settings > Data</strong> usage by using the new
+{@link android.app.usage.NetworkStatsManager} methods. Profile Owners are automatically granted
+permission to query data on the profile they manage, while Device Owners get access to usage data
+of the managed primary user.</li>
+<li><strong>Runtime permission management:</strong>
+<p>A Profile or Device Owner can set a permission policy
+for all runtime requests of all applications using
+{@link android.app.admin.DevicePolicyManager#setPermissionPolicy(android.content.ComponentName, int)
+setPermissionPolicy()}, to either prompt the user to grant the permission or automatically grant or
+deny the permission silently. If the latter policy is set, the user cannot
+modify the selection made by the Profile or Device Owner within the app’s permissions screen in
+<strong>Settings</strong>.</p></li>
+<li><strong>VPN in Settings:</strong> VPN apps are now visible in
+ <strong>Settings > More > VPN</strong>.
+Additionally, the notifications that accompany VPN usage are now specific to how that VPN is
+configured. For Profile Owner, the notifications are specific to whether the VPN is configured
+for a managed profile, a personal profile, or both. For a Device Owner, the notifications are
+specific to whether the VPN is configured for the entire device.</li>
+<li><strong>Work status notification:</strong> A status bar briefcase icon now appears whenever
+an app from the managed profile has an activity in the foreground. Furthermore, if the device is
+unlocked directly to the activity of an app in the managed profile, a toast is displayed notifying
+the user that they are within the work profile.
+</li>
+</ul>
+
+<p class="note">
+ For a detailed view of all API changes in the M Developer Preview, see the <a href=
+ "{@docRoot}preview/download.html">API Differences Report</a>.
+</p>