docs/html/guide/topics/ui/multi-window.jd - platform/frameworks/base - Git at Google

 page.title=Multi-Window Support
 page.metaDescription=New support in Android N for showing more than one app at a time.
 page.keywords="multi-window", "android N", "split screen", "free-form"

 @jd:body

 <div id="qv-wrapper">
   <div id="qv">
     <h2>In this document</h2>
       <ol>
         <li><a href="#overview">Overview</a></li>
         <li><a href="#lifecycle">Multi-Window Lifecycle</a></li>
         <li><a href="#configuring">Configuring Your App for Multi-Window
               Mode</a></li>
         <li><a href="#running">Running Your App in Multi-Window Mode</a></li>
         <li><a href="#testing">Testing Your App's Multi-Window Support</a></li>
       </ol>
     <h2>See Also</h2>
       <ol>
         <li><a href="{@docRoot}training/tv/playback/picture-in-picture.html">Adding
           Picture-in-Picture</a></li>
         <li><a class="external-link"
           href="https://github.com/googlesamples/android-MultiWindowPlayground">Multi-Window
           Playground sample app</a></li>
         <li><a class="external-link"
           href="https://medium.com/google-developers/5-tips-for-preparing-for-multi-window-in-android-n-7bed803dda64"
           >Five Tips for Preparing for Multi-Window in Android N</a></li>
       </ol>
   </div>
 </div>

 <p>
   Android 7.0 adds support for displaying more than one app at the
   same time. On handheld devices, two apps can run side-by-side or
   one-above-the-other in <em>split-screen</em> mode. On TV devices, apps can
   use <em>picture-in-picture</em> mode to continue video playback while users
   are interacting with another app.
 </p>

 <p>
   If your app targets Android 7.0 (API level 24) or higher, you can configure how your app
   handles multi-window display. For example, you can specify your activity's
   minimum allowable dimensions. You can also disable multi-window display for
   your app, ensuring that the system only shows your app in full-screen
   mode.
 </p>

 <h2 id="overview">Overview</h2>

 <p>
   Android 7.0 allows several apps to share the screen at once. For
   example, a user could split the screen, viewing a web page on the left side
   while composing an email on the right side. The user experience depends on
   the device:
 </p>

 <ul>
   <li>Handheld devices running Android 7.0 offer split-screen
   mode. In this mode, the system fills the screen with two apps, showing them
   either side-by-side or one-above-the-other. The user can drag the dividing
   line separating the two to make one app larger and the other smaller.
   </li>

   <li>On TV devices, apps can put themselves
   in <a href="picture-in-picture.html">picture-in-picture mode</a>, allowing
   them to continue showing content while the user browses or interacts with
   other apps.
   </li>

   <li>Manufacturers of larger devices can choose to enable freeform
   mode, in which the user can freely resize each activity. If the
   manufacturer enables this feature, the device offers freeform mode in addition
   to split-screen mode.
   </li>
 </ul>

 <img src="{@docRoot}images/android-7.0/mw-splitscreen.png" alt="" width="650"
     srcset="{@docRoot}images/android-7.0/mw-splitscreen.png 1x,
     {@docRoot}images/android-7.0/mw-splitscreen_2x.png 2x,"
     id="img-split-screen" />
 <p class="img-caption">
   <strong>Figure 1.</strong> Two apps running side-by-side in split-screen mode.
 </p>

 <p>
   The user can switch into multi-window mode in the following ways:
 </p>

 <ul>
   <li>If the user opens the <a href="{@docRoot}guide/components/recents.html">Overview
   screen</a> and performs a long press on an
   activity title, they can drag that activity to a highlighted portion of the
   screen to put the activity in multi-window mode.
   </li>

   <li>If the user performs a long press on the Overview button, the device puts
   the current activity in multi-window mode, and opens the Overview screen to
   let the user choose another activity to share the screen.
   </li>
 </ul>

 <p>
   Users can <a href="{@docRoot}guide/topics/ui/drag-drop.html">drag and
   drop</a> data from one activity to another while the activities are sharing
   the screen.

 <h2 id="lifecycle">Multi-Window Lifecycle</h2>

 <p>
   Multi-window mode does not change the <a href=
   "{@docRoot}training/basics/activity-lifecycle/index.html">activity
   lifecycle</a>.
 </p>

 <p>
   In multi-window mode, only the activity the user has most recently interacted
   with is active at a given time. This activity is considered <em>topmost</em>.
   All other activities are in the paused state, even if they are visible.
   However, the system gives these paused-but-visible activities higher priority
   than activities that are not visible. If the user interacts with one of the
   paused activities, that activity is resumed, and the previously topmost
   activity is paused.
 </p>

 <p class="note">
   <strong>Note:</strong> In multi-window mode, an app can be in the paused
   state and still be visible to the user. An app might need to continue its
   activities even while paused. For example, a video-playing app that is in
   paused mode but is visible should continue showing its video. For this
   reason, we recommend that activities that play video <em>not</em> pause the
   video in their {@link android.app.Activity#onPause onPause()} handlers.
   Instead, they should pause video in {@link android.app.Activity#onStop
   onStop()}, and resume playback in {@link android.app.Activity#onStart
   onStart()}.
 </p>

 <p>
   When the user puts an app into multi-window mode, the system notifies the
   activity of a configuration change, as specified in <a href=
   "{@docRoot}guide/topics/resources/runtime-changes.html">Handling Runtime
   Changes</a>. This also happens when the user resizes the app, or puts the app
   back into full-screen mode.
   Essentially, this change has the same activity-lifecycle
   implications as when the system notifies the app that the device has switched
   from portrait to landscape mode, except that the device dimensions are
   changed instead of just being swapped. As discussed in <a href=
   "{@docRoot}guide/topics/resources/runtime-changes.html">Handling Runtime
   Changes</a>, your activity can handle the configuration change itself, or it
   can allow the system to destroy the activity and recreate it with the new
   dimensions.
 </p>

 <p>
   If the user is resizing a window and makes it larger in either dimension, the
   system resizes the activity to match the user action and issues <a href=
   "{@docRoot}guide/topics/resources/runtime-changes.html">runtime changes</a>
   as needed. If the app lags behind in drawing in newly-exposed areas, the
   system temporarily fills those areas with the color specified by the {@link
   android.R.attr#windowBackground windowBackground} attribute or by the default
   <code>windowBackgroundFallback</code> style attribute.
 </p>

 <h2 id="configuring">Configuring Your App for Multi-Window Mode</h2>

 <p>
   If your app targets API level 24 or higher, you can configure how and
   whether your app's activities support multi-window display. You can set
   attributes in your manifest to control both size and layout.
   A root activity's attribute settings apply to all activities
   within its task stack. For example, if the root activity has
   <code>android:resizeableActivity</code> set to true, then all activities
   in the task stack are resizeable.
 </p>

 <p class="note">
   <strong>Note:</strong> If you build a multi-orientation app that targets API
   level 23 or lower, and the user uses the app in
   multi-window mode, the system forcibly resizes the app. The system presents a
   dialog box warning the user that the app may behave unexpectedly. The system
   does <em>not</em> resize fixed-orientation apps; if
   the user attempts to open a fixed-orientation app under multi-window mode,
   the app takes over the whole screen.
 </p>

 <h4 id="resizeableActivity">android:resizeableActivity</h4>

 <p>
   Set this attribute in your manifest's <a href=
   "{@docRoot}guide/topics/manifest/activity-element"><code>&lt;activity&gt;</code></a>
   or <a href=
   "{@docRoot}guide/topics/manifest/application-element"><code>&lt;application&gt;</code></a>
   element to enable or disable multi-window display:
 </p>

 <pre>
 android:resizeableActivity=["true" | "false"]
 </pre>

 <p>
   If this attribute is set to true, the activity can be launched in
   split-screen and freeform modes. If the attribute is set to false, the
   activity does not support multi-window mode. If this value is false, and the
   user attempts to launch the activity in multi-window mode, the activity takes
   over the full screen.
 </p>

 <p>
   If your app targets API level 24, but you do not specify a value
   for this attribute, the attribute's value defaults to true.
 </p>

 <h4 id="supportsPictureInPicture">android:supportsPictureInPicture</h4>

 <p>
   Set this attribute in your manifest's <a href=
   "{@docRoot}guide/topics/manifest/activity-element"><code>&lt;activity&gt;</code></a>
   node to indicate whether the activity supports <a href=
   "{@docRoot}training/tv/playback/picture-in-picture.jd">Picture-in-Picture</a>
   display. This attribute is ignored if <code>android:resizeableActivity</code>
   is false.
 </p>

 <pre>
 android:supportsPictureInPicture=["true" | "false"]
 </pre>

 <h3 id="layout">Layout attributes</h3>

 <p>
   With Android 7.0, the <code>&lt;layout&gt;</code> manifest element
   supports several attributes that affect how an activity behaves in
   multi-window mode:
 </p>

 <dl>
   <dt>
     <code>android:defaultWidth</code>
   </dt>

   <dd>
     Default width of the activity when launched in freeform mode.
   </dd>

   <dt>
     <code>android:defaultHeight</code>
   </dt>

   <dd>
     Default height of the activity when launched in freeform mode.
   </dd>

   <dt>
     <code>android:gravity</code>
   </dt>

   <dd>
     Initial placement of the activity when launched in freeform mode. See the
     {@link android.view.Gravity} reference for suitable values.
   </dd>

   <dt>
     <code>android:minHeight</code>, <code>android:minWidth</code>
   </dt>

   <dd>
     Minimum height and minimum width for the activity in both split-screen
     and freeform modes. If the user moves the divider in split-screen mode
     to make an activity smaller than the specified minimum, the system crops
     the activity to the size the user requests.
   </dd>
 </dl>

 <p>
   For example, the following code shows how to specify an activity's default
   size and location, and its minimum size, when the activity is displayed in
   freeform mode:
 </p>

 <pre>
 &lt;activity android:name=".MyActivity"&gt;
     &lt;layout android:defaultHeight="500dp"
           android:defaultWidth="600dp"
           android:gravity="top|end"
           android:minHeight="450dp"
           android:minWidth="300dp" /&gt;
 &lt;/activity&gt;
 </pre>

 <h2 id="running">Running Your App in Multi-Window Mode</h2>

 <p>
   Beginning with Android 7.0, the system offers functionality to support apps
   that can run in multi-window mode.
 </p>

 <h3 id="disabled-features">Disabled features in multi-window mode</h3>

 <p>
   Certain features are disabled or ignored when a device is in multi-window
   mode, because they don’t make sense for an activity which may be sharing the
   device screen with other activities or apps. Such features include:

 <ul>
   <li>Some <a href="{@docRoot}training/system-ui/index.html">System UI</a>
   customization options are disabled; for example, apps cannot hide the status
   bar if they are not running in full-screen mode.
   </li>

   <li>The system ignores changes to the <code><a href=
   "{@docRoot}guide/topics/manifest/activity-element.html#screen"
   >android:screenOrientation</a></code> attribute.
   </li>
 </ul>

 <h3 id="change-notification">Multi-window change notification and querying</h3>

 <p>
   {@link android.app.Activity} offers the following methods to support
   multi-window display.
 </p>

 <dl>
   <dt>
     {@link android.app.Activity#isInMultiWindowMode isInMultiWindowMode()}
   </dt>

   <dd>
     Call to find out if the activity is in multi-window mode.
   </dd>

   <dt>
     {@link android.app.Activity#isInPictureInPictureMode
     isInPictureInPictureMode()}
   </dt>

   <dd>
     Call to find out if the activity is in <a href=
     "{@docRoot}training/tv/playback/picture-in-picture.jd">picture-in-picture</a>
     mode.
     <p class="note">
       <strong>Note:</strong> Picture-in-picture mode is a special case of
       multi-window mode. If <code>myActivity.isInPictureInPictureMode()</code>
       returns true, then <code>myActivity.isInMultiWindowMode()</code> also
       returns true.
     </p>
   </dd>

   <dt>
     {@link android.app.Activity#onMultiWindowModeChanged
     onMultiWindowModeChanged()}
   </dt>

   <dd>
     The system calls this method whenever the activity goes into or out of
     multi-window mode. The system passes the method a value of true if the
     activity is entering multi-window mode, and false if the activity is
     leaving multi-window mode.
   </dd>

   <dt>
     {@link android.app.Activity#onPictureInPictureModeChanged
     onPictureInPictureModeChanged()}
   </dt>

   <dd>
     The system calls this method whenever the activity goes into or out of
     picture-in-picture mode. The system passes the method a value of true if
     the activity is entering picture-in-picture mode, and false if the activity
     is leaving picture-in-picture mode.
   </dd>
 </dl>

 <p>
   The {@link android.app.Fragment} class exposes versions of many of these
   methods, for example {@link android.app.Fragment#onMultiWindowModeChanged
   Fragment.onMultiWindowModeChanged()}.
 </p>

 <h3 id="entering-pip">Entering picture-in-picture mode</h3>

 <p>
   To put an activity in picture-in-picture mode, call {@link
   android.app.Activity#enterPictureInPictureMode
   Activity.enterPictureInPictureMode()}. This method has no effect if the
   device does not support picture-in-picture mode. For more information, see
   the <a href=
   "{@docRoot}training/tv/playback/picture-in-picture.jd">Picture-in-Picture</a>
   documentation.
 </p>

 <h3 id="launch">Launch New Activities in Multi-Window Mode</h3>

 <p>
   When you launch a new activity, you can hint to the system that the new
   activity should be displayed adjacent to the current one, if possible. To do
   this, use the intent flag
   {@link android.content.Intent#FLAG_ACTIVITY_LAUNCH_ADJACENT}. Passing
   this flag requests the following behavior:
 </p>

 <ul>
   <li>If the device is in split-screen mode, the system attempts to create the
   new activity next to the activity that launched it, so the two activities
   share the screen. The system is not guaranteed to be able to do this, but it
   makes the activities adjacent if possible.
   </li>

   <li>If the device is not in split-screen mode, this flag has no effect.
   </li>
 </ul>

 <p>
   If a device is in freeform mode and you are launching a new activity, you can
   specify the new activity's dimensions and screen location by calling
   {@link android.app.ActivityOptions#setLaunchBounds
   ActivityOptions.setLaunchBounds()}. This method has no effect if
   the device is not in multi-window mode.
 </p>

 <p class="note">
   <strong>Note:</strong> If you launch an activity within a task stack, the
   activity replaces the activity on the screen, inheriting all of its
   multi-window properties. If you want to launch the new activity as a separate
   window in multi-window mode, you must launch it in a new task stack.
 </p>

 <h3 id="dnd">Supporting drag and drop</h3>

 <p>
   Users can <a href="{@docRoot}guide/topics/ui/drag-drop.html">drag and
   drop</a> data from one activity to another while the two activities are
   sharing the screen. (Prior to Android 7.0, users could only drag and drop data
   within a single activity.) For this reason, you may want to add drag and drop
   functionality to your app if your app does not currently support it.
 </p>


 <dl>
   <dt>
     {@link android.view.DragAndDropPermissions}
   </dt>

   <dd>
     Token object responsible for specifying the permissions granted to the app
     that receives a drop.
   </dd>

   <dt>
     {@link android.view.View#startDragAndDrop View.startDragAndDrop()}
   </dt>

   <dd>
     Alias for {@link android.view.View#startDrag View.startDrag()}. To enable
     cross-activity drag and drop, pass the flag {@link
     android.view.View#DRAG_FLAG_GLOBAL}. If you need to give URI permissions to
     the recipient activity, pass the flags {@link
     android.view.View#DRAG_FLAG_GLOBAL_URI_READ} or {@link
     android.view.View#DRAG_FLAG_GLOBAL_URI_WRITE}, as appropriate.
   </dd>

   <dt>
     {@link android.view.View#cancelDragAndDrop View.cancelDragAndDrop()}
   </dt>

   <dd>
     Cancels a drag operation currently in progress. Can only be called by the
     app that originated the drag operation.
   </dd>

   <dt>
     {@link android.view.View#updateDragShadow View.updateDragShadow()}
   </dt>

   <dd>
     Replaces the drag shadow for a drag operation currently in progress. Can
     only be called by the app that originated the drag operation.
   </dd>

   <dt>
     {@link android.app.Activity#requestDragAndDropPermissions
     Activity.requestDragAndDropPermissions()}
   </dt>

   <dd>
     Requests the permissions for the content URIs passed with the {@link
     android.content.ClipData} contained in a {@link android.view.DragEvent}.
   </dd>
 </dl>

 <h2 id="testing">Testing Your App's Multi-Window Support</h2>

 <p>
   Whether or not your app targets API level 24 or higher, you should
   verify how it behaves in multi-window mode in case a user tries to launch it
   in multi-window mode on a device running Android 7.0 or higher.
 </p>

 <h3 id="configuring">Configuring a Test Device</h3>

 <p>
   If a device runs Android 7.0 or higher, it automatically supports split-screen
   mode.
 </p>

 <h3 id="test-non-n">If your app targets API level 23 or lower</h3>

 <p>
   If your app targets API level 23 or lower and the user attempts to use
   the app in multi-window mode, the system forcibly resizes the app unless the
   app declares a fixed orientation.
 </p>

 <p>
   If your app does not declare a fixed orientation, you should launch your app
   on a device running Android 7.0 or higher and attempt to put the app in
   split-screen mode. Verify that the user experience is
   acceptable when the app is forcibly resized.
 </p>

 <p>
   If the app declares a fixed orientation, you should attempt to put the app in
   multi-window mode. Verify that when you do so, the app remains
   in full-screen mode.
 </p>

 <h3 id="test-mw">If you support multi-window mode</h3>

 <p>
   If your app targets API level 24 or higher and does not disable
   multi-window support, verify the following behavior under both split-screen
   and freeform modes.
 </p>

 <ul>
   <li>Launch the app in full-screen mode, then switch to multi-window mode by
   long-pressing the Overview button. Verify that the app switches properly.
   </li>

   <li>Launch the app directly in multi-window mode, and verify that the app
   launches properly. You can launch an app in multi-window mode by pressing the
   Overview button, then long-pressing the title bar of your app and dragging it
   to one of the highlighted areas on the screen.
   </li>

   <li>Resize your app in split-screen mode by dragging the divider line.
   Verify that the app resizes without crashing, and that necessary UI elements
   are visible.
   </li>

   <li>If you have specified minimum dimensions for your app, attempt to resize
   the app below those dimensions. Verify that you cannot resize the app to be
   smaller than the specified minimum.
   </li>

   <li>Through all tests, verify that your app's performance is acceptable. For
   example, verify that there is not too long a lag to update the UI after the
   app is resized.
   </li>
 </ul>

 <h4 id="test-checklist">Testing checklist</h4>

 <p>
   To verify your app's performance in multi-window mode, try the following
   operations. You should try these operations in both split-screen and
   multi-window mode, except where otherwise noted.
 </p>

 <ul>
   <li>Enter and leave multi-window mode.
   </li>

   <li>Switch from your app to another app, and verify that the app behaves
   properly while it is visible but not active. For example, if your app is
   playing video, verify that the video continues to play while the user is
   interacting with another app.
   </li>

   <li>In split-screen mode, try moving the dividing bar to make your app both
   larger and smaller. Try these operations in both side-by-side and
   one-above-the-other configurations. Verify that the app does not crash,
   essential functionality is visible, and the resize operation doesn't take too
   long.
   </li>

   <li>Perform several resize operations in rapid succession. Verify that your
   app doesn't crash or leak memory. For information about checking your app's
   memory usage, see <a href="{@docRoot}tools/debugging/debugging-memory.html">
   Investigating Your RAM Usage</a>.
   </li>

   <li>Use your app normally in a number of different window configurations, and
   verify that the app behaves properly. Verify that text is readable, and that
   UI elements aren't too small to interact with.
   </li>
 </ul>

 <h3 id="test-disabled-mw">If you have disabled multi-window support</h3>

 <p>
   If you disabled multi-window support by setting
   <code>android:resizableActivity="false"</code>, you should launch your app on
   a device running Android 7.0 or higher and attempt to put the app in
   freeform and split-screen modes. Verify that when you do so, the app remains
   in full-screen mode.
 </p>
	page.title=Multi-Window Support
	page.metaDescription=New support in Android N for showing more than one app at a time.
	page.keywords="multi-window", "android N", "split screen", "free-form"

	@jd:body

	<div id="qv-wrapper">
	<div id="qv">
	<h2>In this document</h2>
	<ol>
	<li><a href="#overview">Overview</a></li>
	<li><a href="#lifecycle">Multi-Window Lifecycle</a></li>
	<li><a href="#configuring">Configuring Your App for Multi-Window
	Mode</a></li>
	<li><a href="#running">Running Your App in Multi-Window Mode</a></li>
	<li><a href="#testing">Testing Your App's Multi-Window Support</a></li>
	</ol>
	<h2>See Also</h2>
	<ol>
	<li><a href="{@docRoot}training/tv/playback/picture-in-picture.html">Adding
	Picture-in-Picture</a></li>
	<li><a class="external-link"
	href="https://github.com/googlesamples/android-MultiWindowPlayground">Multi-Window
	Playground sample app</a></li>
	<li><a class="external-link"
	href="https://medium.com/google-developers/5-tips-for-preparing-for-multi-window-in-android-n-7bed803dda64"
	>Five Tips for Preparing for Multi-Window in Android N</a></li>
	</ol>
	</div>
	</div>

	<p>
	Android 7.0 adds support for displaying more than one app at the
	same time. On handheld devices, two apps can run side-by-side or
	one-above-the-other in <em>split-screen</em> mode. On TV devices, apps can
	use <em>picture-in-picture</em> mode to continue video playback while users
	are interacting with another app.
	</p>

	<p>
	If your app targets Android 7.0 (API level 24) or higher, you can configure how your app
	handles multi-window display. For example, you can specify your activity's
	minimum allowable dimensions. You can also disable multi-window display for
	your app, ensuring that the system only shows your app in full-screen
	mode.
	</p>

	<h2 id="overview">Overview</h2>

	<p>
	Android 7.0 allows several apps to share the screen at once. For
	example, a user could split the screen, viewing a web page on the left side
	while composing an email on the right side. The user experience depends on
	the device:
	</p>

	<ul>
	<li>Handheld devices running Android 7.0 offer split-screen
	mode. In this mode, the system fills the screen with two apps, showing them
	either side-by-side or one-above-the-other. The user can drag the dividing
	line separating the two to make one app larger and the other smaller.
	</li>

	<li>On TV devices, apps can put themselves
	in <a href="picture-in-picture.html">picture-in-picture mode</a>, allowing
	them to continue showing content while the user browses or interacts with
	other apps.
	</li>

	<li>Manufacturers of larger devices can choose to enable freeform
	mode, in which the user can freely resize each activity. If the
	manufacturer enables this feature, the device offers freeform mode in addition
	to split-screen mode.
	</li>
	</ul>

	<img src="{@docRoot}images/android-7.0/mw-splitscreen.png" alt="" width="650"
	srcset="{@docRoot}images/android-7.0/mw-splitscreen.png 1x,
	{@docRoot}images/android-7.0/mw-splitscreen_2x.png 2x,"
	id="img-split-screen" />
	<p class="img-caption">
	<strong>Figure 1.</strong> Two apps running side-by-side in split-screen mode.
	</p>

	<p>
	The user can switch into multi-window mode in the following ways:
	</p>

	<ul>
	<li>If the user opens the <a href="{@docRoot}guide/components/recents.html">Overview
	screen</a> and performs a long press on an
	activity title, they can drag that activity to a highlighted portion of the
	screen to put the activity in multi-window mode.
	</li>

	<li>If the user performs a long press on the Overview button, the device puts
	the current activity in multi-window mode, and opens the Overview screen to
	let the user choose another activity to share the screen.
	</li>
	</ul>

	<p>
	Users can <a href="{@docRoot}guide/topics/ui/drag-drop.html">drag and
	drop</a> data from one activity to another while the activities are sharing
	the screen.

	<h2 id="lifecycle">Multi-Window Lifecycle</h2>

	<p>
	Multi-window mode does not change the <a href=
	"{@docRoot}training/basics/activity-lifecycle/index.html">activity
	lifecycle</a>.
	</p>

	<p>
	In multi-window mode, only the activity the user has most recently interacted
	with is active at a given time. This activity is considered <em>topmost</em>.
	All other activities are in the paused state, even if they are visible.
	However, the system gives these paused-but-visible activities higher priority
	than activities that are not visible. If the user interacts with one of the
	paused activities, that activity is resumed, and the previously topmost
	activity is paused.
	</p>

	<p class="note">
	<strong>Note:</strong> In multi-window mode, an app can be in the paused
	state and still be visible to the user. An app might need to continue its
	activities even while paused. For example, a video-playing app that is in
	paused mode but is visible should continue showing its video. For this
	reason, we recommend that activities that play video <em>not</em> pause the
	video in their {@link android.app.Activity#onPause onPause()} handlers.
	Instead, they should pause video in {@link android.app.Activity#onStop
	onStop()}, and resume playback in {@link android.app.Activity#onStart
	onStart()}.
	</p>

	<p>
	When the user puts an app into multi-window mode, the system notifies the
	activity of a configuration change, as specified in <a href=
	"{@docRoot}guide/topics/resources/runtime-changes.html">Handling Runtime
	Changes</a>. This also happens when the user resizes the app, or puts the app
	back into full-screen mode.
	Essentially, this change has the same activity-lifecycle
	implications as when the system notifies the app that the device has switched
	from portrait to landscape mode, except that the device dimensions are
	changed instead of just being swapped. As discussed in <a href=
	"{@docRoot}guide/topics/resources/runtime-changes.html">Handling Runtime
	Changes</a>, your activity can handle the configuration change itself, or it
	can allow the system to destroy the activity and recreate it with the new
	dimensions.
	</p>

	<p>
	If the user is resizing a window and makes it larger in either dimension, the
	system resizes the activity to match the user action and issues <a href=
	"{@docRoot}guide/topics/resources/runtime-changes.html">runtime changes</a>
	as needed. If the app lags behind in drawing in newly-exposed areas, the
	system temporarily fills those areas with the color specified by the {@link
	android.R.attr#windowBackground windowBackground} attribute or by the default
	<code>windowBackgroundFallback</code> style attribute.
	</p>

	<h2 id="configuring">Configuring Your App for Multi-Window Mode</h2>

	<p>
	If your app targets API level 24 or higher, you can configure how and
	whether your app's activities support multi-window display. You can set
	attributes in your manifest to control both size and layout.
	A root activity's attribute settings apply to all activities
	within its task stack. For example, if the root activity has
	<code>android:resizeableActivity</code> set to true, then all activities
	in the task stack are resizeable.
	</p>

	<p class="note">
	<strong>Note:</strong> If you build a multi-orientation app that targets API
	level 23 or lower, and the user uses the app in
	multi-window mode, the system forcibly resizes the app. The system presents a
	dialog box warning the user that the app may behave unexpectedly. The system
	does <em>not</em> resize fixed-orientation apps; if
	the user attempts to open a fixed-orientation app under multi-window mode,
	the app takes over the whole screen.
	</p>

	<h4 id="resizeableActivity">android:resizeableActivity</h4>

	<p>
	Set this attribute in your manifest's <a href=
	"{@docRoot}guide/topics/manifest/activity-element"><code><activity></code></a>
	or <a href=
	"{@docRoot}guide/topics/manifest/application-element"><code><application></code></a>
	element to enable or disable multi-window display:
	</p>

	<pre>
	android:resizeableActivity=["true" \| "false"]
	</pre>

	<p>
	If this attribute is set to true, the activity can be launched in
	split-screen and freeform modes. If the attribute is set to false, the
	activity does not support multi-window mode. If this value is false, and the
	user attempts to launch the activity in multi-window mode, the activity takes
	over the full screen.
	</p>

	<p>
	If your app targets API level 24, but you do not specify a value
	for this attribute, the attribute's value defaults to true.
	</p>

	<h4 id="supportsPictureInPicture">android:supportsPictureInPicture</h4>

	<p>
	Set this attribute in your manifest's <a href=
	"{@docRoot}guide/topics/manifest/activity-element"><code><activity></code></a>
	node to indicate whether the activity supports <a href=
	"{@docRoot}training/tv/playback/picture-in-picture.jd">Picture-in-Picture</a>
	display. This attribute is ignored if <code>android:resizeableActivity</code>
	is false.
	</p>

	<pre>
	android:supportsPictureInPicture=["true" \| "false"]
	</pre>

	<h3 id="layout">Layout attributes</h3>

	<p>
	With Android 7.0, the <code><layout></code> manifest element
	supports several attributes that affect how an activity behaves in
	multi-window mode:
	</p>

	<dl>
	<dt>
	<code>android:defaultWidth</code>
	</dt>

	<dd>
	Default width of the activity when launched in freeform mode.
	</dd>

	<dt>
	<code>android:defaultHeight</code>
	</dt>

	<dd>
	Default height of the activity when launched in freeform mode.
	</dd>

	<dt>
	<code>android:gravity</code>
	</dt>

	<dd>
	Initial placement of the activity when launched in freeform mode. See the
	{@link android.view.Gravity} reference for suitable values.
	</dd>

	<dt>
	<code>android:minHeight</code>, <code>android:minWidth</code>
	</dt>

	<dd>
	Minimum height and minimum width for the activity in both split-screen
	and freeform modes. If the user moves the divider in split-screen mode
	to make an activity smaller than the specified minimum, the system crops
	the activity to the size the user requests.
	</dd>
	</dl>

	<p>
	For example, the following code shows how to specify an activity's default
	size and location, and its minimum size, when the activity is displayed in
	freeform mode:
	</p>

	<pre>
	<activity android:name=".MyActivity">
	<layout android:defaultHeight="500dp"
	android:defaultWidth="600dp"
	android:gravity="top\|end"
	android:minHeight="450dp"
	android:minWidth="300dp" />
	</activity>
	</pre>

	<h2 id="running">Running Your App in Multi-Window Mode</h2>

	<p>
	Beginning with Android 7.0, the system offers functionality to support apps
	that can run in multi-window mode.
	</p>

	<h3 id="disabled-features">Disabled features in multi-window mode</h3>

	<p>
	Certain features are disabled or ignored when a device is in multi-window
	mode, because they don’t make sense for an activity which may be sharing the
	device screen with other activities or apps. Such features include:

	<ul>
	<li>Some <a href="{@docRoot}training/system-ui/index.html">System UI</a>
	customization options are disabled; for example, apps cannot hide the status
	bar if they are not running in full-screen mode.
	</li>

	<li>The system ignores changes to the <code><a href=
	"{@docRoot}guide/topics/manifest/activity-element.html#screen"
	>android:screenOrientation</a></code> attribute.
	</li>
	</ul>

	<h3 id="change-notification">Multi-window change notification and querying</h3>

	<p>
	{@link android.app.Activity} offers the following methods to support
	multi-window display.
	</p>

	<dl>
	<dt>
	{@link android.app.Activity#isInMultiWindowMode isInMultiWindowMode()}
	</dt>

	<dd>
	Call to find out if the activity is in multi-window mode.
	</dd>

	<dt>
	{@link android.app.Activity#isInPictureInPictureMode
	isInPictureInPictureMode()}
	</dt>

	<dd>
	Call to find out if the activity is in <a href=
	"{@docRoot}training/tv/playback/picture-in-picture.jd">picture-in-picture</a>
	mode.
	<p class="note">
	<strong>Note:</strong> Picture-in-picture mode is a special case of
	multi-window mode. If <code>myActivity.isInPictureInPictureMode()</code>
	returns true, then <code>myActivity.isInMultiWindowMode()</code> also
	returns true.
	</p>
	</dd>

	<dt>
	{@link android.app.Activity#onMultiWindowModeChanged
	onMultiWindowModeChanged()}
	</dt>

	<dd>
	The system calls this method whenever the activity goes into or out of
	multi-window mode. The system passes the method a value of true if the
	activity is entering multi-window mode, and false if the activity is
	leaving multi-window mode.
	</dd>

	<dt>
	{@link android.app.Activity#onPictureInPictureModeChanged
	onPictureInPictureModeChanged()}
	</dt>

	<dd>
	The system calls this method whenever the activity goes into or out of
	picture-in-picture mode. The system passes the method a value of true if
	the activity is entering picture-in-picture mode, and false if the activity
	is leaving picture-in-picture mode.
	</dd>
	</dl>

	<p>
	The {@link android.app.Fragment} class exposes versions of many of these
	methods, for example {@link android.app.Fragment#onMultiWindowModeChanged
	Fragment.onMultiWindowModeChanged()}.
	</p>

	<h3 id="entering-pip">Entering picture-in-picture mode</h3>

	<p>
	To put an activity in picture-in-picture mode, call {@link
	android.app.Activity#enterPictureInPictureMode
	Activity.enterPictureInPictureMode()}. This method has no effect if the
	device does not support picture-in-picture mode. For more information, see
	the <a href=
	"{@docRoot}training/tv/playback/picture-in-picture.jd">Picture-in-Picture</a>
	documentation.
	</p>

	<h3 id="launch">Launch New Activities in Multi-Window Mode</h3>

	<p>
	When you launch a new activity, you can hint to the system that the new
	activity should be displayed adjacent to the current one, if possible. To do
	this, use the intent flag
	{@link android.content.Intent#FLAG_ACTIVITY_LAUNCH_ADJACENT}. Passing
	this flag requests the following behavior:
	</p>

	<ul>
	<li>If the device is in split-screen mode, the system attempts to create the
	new activity next to the activity that launched it, so the two activities
	share the screen. The system is not guaranteed to be able to do this, but it
	makes the activities adjacent if possible.
	</li>

	<li>If the device is not in split-screen mode, this flag has no effect.
	</li>
	</ul>

	<p>
	If a device is in freeform mode and you are launching a new activity, you can
	specify the new activity's dimensions and screen location by calling
	{@link android.app.ActivityOptions#setLaunchBounds
	ActivityOptions.setLaunchBounds()}. This method has no effect if
	the device is not in multi-window mode.
	</p>

	<p class="note">
	<strong>Note:</strong> If you launch an activity within a task stack, the
	activity replaces the activity on the screen, inheriting all of its
	multi-window properties. If you want to launch the new activity as a separate
	window in multi-window mode, you must launch it in a new task stack.
	</p>

	<h3 id="dnd">Supporting drag and drop</h3>

	<p>
	Users can <a href="{@docRoot}guide/topics/ui/drag-drop.html">drag and
	drop</a> data from one activity to another while the two activities are
	sharing the screen. (Prior to Android 7.0, users could only drag and drop data
	within a single activity.) For this reason, you may want to add drag and drop
	functionality to your app if your app does not currently support it.
	</p>


	<dl>
	<dt>
	{@link android.view.DragAndDropPermissions}
	</dt>

	<dd>
	Token object responsible for specifying the permissions granted to the app
	that receives a drop.
	</dd>

	<dt>
	{@link android.view.View#startDragAndDrop View.startDragAndDrop()}
	</dt>

	<dd>
	Alias for {@link android.view.View#startDrag View.startDrag()}. To enable
	cross-activity drag and drop, pass the flag {@link
	android.view.View#DRAG_FLAG_GLOBAL}. If you need to give URI permissions to
	the recipient activity, pass the flags {@link
	android.view.View#DRAG_FLAG_GLOBAL_URI_READ} or {@link
	android.view.View#DRAG_FLAG_GLOBAL_URI_WRITE}, as appropriate.
	</dd>

	<dt>
	{@link android.view.View#cancelDragAndDrop View.cancelDragAndDrop()}
	</dt>

	<dd>
	Cancels a drag operation currently in progress. Can only be called by the
	app that originated the drag operation.
	</dd>

	<dt>
	{@link android.view.View#updateDragShadow View.updateDragShadow()}
	</dt>

	<dd>
	Replaces the drag shadow for a drag operation currently in progress. Can
	only be called by the app that originated the drag operation.
	</dd>

	<dt>
	{@link android.app.Activity#requestDragAndDropPermissions
	Activity.requestDragAndDropPermissions()}
	</dt>

	<dd>
	Requests the permissions for the content URIs passed with the {@link
	android.content.ClipData} contained in a {@link android.view.DragEvent}.
	</dd>
	</dl>

	<h2 id="testing">Testing Your App's Multi-Window Support</h2>

	<p>
	Whether or not your app targets API level 24 or higher, you should
	verify how it behaves in multi-window mode in case a user tries to launch it
	in multi-window mode on a device running Android 7.0 or higher.
	</p>

	<h3 id="configuring">Configuring a Test Device</h3>

	<p>
	If a device runs Android 7.0 or higher, it automatically supports split-screen
	mode.
	</p>

	<h3 id="test-non-n">If your app targets API level 23 or lower</h3>

	<p>
	If your app targets API level 23 or lower and the user attempts to use
	the app in multi-window mode, the system forcibly resizes the app unless the
	app declares a fixed orientation.
	</p>

	<p>
	If your app does not declare a fixed orientation, you should launch your app
	on a device running Android 7.0 or higher and attempt to put the app in
	split-screen mode. Verify that the user experience is
	acceptable when the app is forcibly resized.
	</p>

	<p>
	If the app declares a fixed orientation, you should attempt to put the app in
	multi-window mode. Verify that when you do so, the app remains
	in full-screen mode.
	</p>

	<h3 id="test-mw">If you support multi-window mode</h3>

	<p>
	If your app targets API level 24 or higher and does not disable
	multi-window support, verify the following behavior under both split-screen
	and freeform modes.
	</p>

	<ul>
	<li>Launch the app in full-screen mode, then switch to multi-window mode by
	long-pressing the Overview button. Verify that the app switches properly.
	</li>

	<li>Launch the app directly in multi-window mode, and verify that the app
	launches properly. You can launch an app in multi-window mode by pressing the
	Overview button, then long-pressing the title bar of your app and dragging it
	to one of the highlighted areas on the screen.
	</li>

	<li>Resize your app in split-screen mode by dragging the divider line.
	Verify that the app resizes without crashing, and that necessary UI elements
	are visible.
	</li>

	<li>If you have specified minimum dimensions for your app, attempt to resize
	the app below those dimensions. Verify that you cannot resize the app to be
	smaller than the specified minimum.
	</li>

	<li>Through all tests, verify that your app's performance is acceptable. For
	example, verify that there is not too long a lag to update the UI after the
	app is resized.
	</li>
	</ul>

	<h4 id="test-checklist">Testing checklist</h4>

	<p>
	To verify your app's performance in multi-window mode, try the following
	operations. You should try these operations in both split-screen and
	multi-window mode, except where otherwise noted.
	</p>

	<ul>
	<li>Enter and leave multi-window mode.
	</li>

	<li>Switch from your app to another app, and verify that the app behaves
	properly while it is visible but not active. For example, if your app is
	playing video, verify that the video continues to play while the user is
	interacting with another app.
	</li>

	<li>In split-screen mode, try moving the dividing bar to make your app both
	larger and smaller. Try these operations in both side-by-side and
	one-above-the-other configurations. Verify that the app does not crash,
	essential functionality is visible, and the resize operation doesn't take too
	long.
	</li>

	<li>Perform several resize operations in rapid succession. Verify that your
	app doesn't crash or leak memory. For information about checking your app's
	memory usage, see <a href="{@docRoot}tools/debugging/debugging-memory.html">
	Investigating Your RAM Usage</a>.
	</li>

	<li>Use your app normally in a number of different window configurations, and
	verify that the app behaves properly. Verify that text is readable, and that
	UI elements aren't too small to interact with.
	</li>
	</ul>

	<h3 id="test-disabled-mw">If you have disabled multi-window support</h3>

	<p>
	If you disabled multi-window support by setting
	<code>android:resizableActivity="false"</code>, you should launch your app on
	a device running Android 7.0 or higher and attempt to put the app in
	freeform and split-screen modes. Verify that when you do so, the app remains
	in full-screen mode.
	</p>