How To Add Apps To Multi Window Without Root

Android enables multiple apps to share the same screen simultaneously. The system can display two apps side by side (split-screen mode), one app in a small window overlaying other apps (picture-in-picture mode), or individual apps in separate movable, resizeable windows (free-form mode).

Two apps running side by side in split-screen mode.

Figure 1. Two apps running side by side in split-screen mode.

The user experience depends on the version of the Android OS and the kind of device:

Android 7.0 provides split-screen mode on handheld devices and picture-in-picture mode on TVs.

Split-screen mode fills the screen with two apps, showing them either side by side or one above the other. Users can drag the divider separating the two apps to make one larger and the other smaller.

Picture-in-picture mode enables users to continue video playback while interacting with another app (see Picture-in-picture support).

Manufacturers of larger devices can choose to enable free-form mode, in which users can freely resize each activity.

You can configure how your app handles multi-window display by specifying your activity's minimum allowable dimensions. You can also disable multi-window display for your app by setting resizeableActivity="false" to ensure the system always shows your app full screen.
Android 8.0 extends picture-in-picture mode to handheld devices.
Android 12 makes multi-window mode standard behavior.

On large screens (sw >= 600dp), the platform supports all apps in multi-window mode regardless of app configuration. If resizeableActivity="false", the app is put into compatibility mode when necessary to accommodate display dimensions.

On small screens (sw < 600dp), the system checks an activity's minWidth and minHeight to determine whether the activity can run in multi-window mode. If resizeableActivity="false", the app is prevented from running in multi‑window mode regardless of minimum width and height.

Note: Device manufacturers can override these behaviors.

Split-screen mode activation

Users can activate split-screen mode by doing the following:

Open the Recents screen
Swipe an app into view
Press the app icon in the app title bar
Select the Split screen menu option
Select another app from the Recents screen, or close the Recents screen and run another app

Users can exit split-screen mode by dragging the window divider to the edge of the screen in either direction.

Multi-window lifecycle

Multi-window mode does not change the activity lifecycle. However, the resumed state of apps in multiple windows varies on different versions of Android.

Multi-resume

On Android 10 (API level 29) and higher, all activities remain in the RESUMED state when the device is in multi-window mode. This is called multi‑resume. Note that an activity can be paused if there's a transparent activity on top or the activity is not focusable (e.g., picture-in-picture mode). It's also possible that no activities have focus at a given time; for example, if the notification drawer is open. The onStop method works as usual; the method is called any time an activity is taken off the screen.

Multi-resume is also available on select devices running Android 9. To opt in to multi-resume on those devices, add the following manifest metadata:

          <meta-data android:name="android.allow_multiple_resumed_activities" android:value="true" />

To verify that a given device supports this manifest metadata, refer to the device specifications.

Android 9

In multi-window mode on Android 9 (API level 28) and lower, only the activity the user has most recently interacted with is active at a given time. This activity is considered topmost, and is the only activity in the RESUMED state. All other visible activities are STARTED but are not RESUMED. However, the system gives these visible but not resumed activities higher priority than activities that are not visible. If the user interacts with one of the visible activities, that activity is resumed, and the previously topmost activity enters the STARTED state.

When there are multiple activities within a single active app process, the activity with the highest z-order is resumed and the others are paused.

Note: In multi-window mode on Android 9 and lower, an app might not be in the RESUMED state even though it is visible to the user, but the app might need to continue its operation while it is not topmost. For example, a video app in this state should continue playing its video. For \this reason, we recommend that activities that play video not pause video playback in response to the ON_PAUSE lifecycle event. Instead, the activity should begin playback in response to ON_START, and pause playback in response to ON_STOP. If you handle the lifecycle events directly instead of using the Lifecycle package, pause video playback in your onStop() handler, and resume playback in onStart().

Configuration changes

When the user puts an app into multi-window mode, the system notifies the activity of a configuration change as specified in Handle configuration changes. 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 orientation, except that the device dimensions are changed instead of just being swapped. As discussed in Handle configuration changes, 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.

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 configuration changes 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 windowBackground attribute or by the default windowBackgroundFallback style attribute.

Exclusive resource access

To help support the multi-resume feature, there's a new lifecycle callback, onTopResumedActivityChanged().

This method is invoked when an activity gains or loses the top resumed activity position. This is important to know when an activity uses a shared singleton resource, such as the microphone or camera.

Kotlin

override fun onTopResumedActivityChanged(topResumed: Boolean) {     if (topResumed) {         // Top resumed activity         // Can be a signal to re-acquire exclusive resources     } else {         // No longer the top resumed activity     } }

Java

@Override public void onTopResumedActivityChanged(boolean topResumed) {     if (topResumed) {         // Top resumed activity         // Can be a signal to re-acquire exclusive resources     } else {         // No longer the top resumed activity     } }

Note that an app can lose resources for other reasons, such as removal of a shared piece of hardware.

In any case, an app should gracefully handle events and state changes that affect available resources.

For apps that use a camera, CameraManager.AvailabilityCallback#onCameraAccessPrioritiesChanged() provides a hint that it might be a good time to try to get access to the camera. This method is available as of Android 10 (API level 29).

Remember that resizeableActivity=false is not a guarantee of exclusive camera access, since other apps that use the camera can be opened on other displays.

Camera in multi-window mode.

Figure 2. Camera in multi-window mode.

Your app does not necessary have to release the camera when the app loses focus. For example, you might want to continue camera preview while the user interacts with the newly focused topmost resumed app. It's fine for your app to keep running the camera when it's not the topmost resumed app, but it has to handle the disconnect case properly. When the topmost resumed app wants to use the camera, it can open it, and your app will lose access. Your app can reopen the camera when the app gets the focus back.

After an app receives a CameraDevice.StateCallback#onDisconnected() callback, subsequent calls on the camera device will throw a CameraAccessException.

Multi-display

Android 10 (API level 29) supports activities on secondary displays. If an activity is running on a device with multiple displays, users can move the activity from one display to another. Multi-resume applies to multi-screen scenarios as well; several activities can receive user input at the same time.

An app can specify which display it should run on when it launches or when it creates another activity. This behavior depends on the activity launch mode defined in the manifest file and on the intent flags and options set by the entity launching the activity. See ActivityOptions for more details.

When an activity moves to a secondary display, it can go through a context update, window resizing, and configuration and resource changes. If the activity handles the configuration change, the activity is notified in onConfigurationChanged(); otherwise, the activity is relaunched.

An activity should check the current display in onCreate and onConfigurationChanged if handling the configuration change. Make sure to update the resources and layouts when the display changes.

If the selected launch mode for an activity allows multiple instances, launching on a secondary screen can create a new instance of the activity. Both activities will be resumed at the same time.

Multiple instances of an activity on multiple displays.

Figure 3. Multiple instances of an activity on multiple displays.

You may also want to read about the multi-display APIs that were introduced in Android 8.0.

Activity vs application context

Using the right context is crucial in multi-display. When accessing resources, the activity context (which is displayed) is different from the application context (which is not).

The activity context contains information about the display and is always adjusted for the display area in which the activity appears. This enables you to get the correct information about the display density or window metrics your app currently has. You should always be using the activity context (or another UI-based context) to get information about the current window or display. This also affects some system APIs that use information from the context (for example, see Toasts overview).

The activity window configuration and parent display define resources and context. Get the current display as follows:

Kotlin

val activityDisplay = activity.getDisplay()

Java

Display activityDisplay = activity.getDisplay();

Get the current activity window metrics:

Kotlin

val windowMetrics = activity.getWindowManager().getCurrentWindowMetrics()

Java

WindowMetrics windowMetrics = activity.getWindowManager().getCurrentWindowMetrics();

Get the maximum window metrics for the current system configuration:

Kotlin

val maximumWindowMetrics = activity.getWindowManager().getMaximumWindowMetrics()

Java

WindowMetrics maximumWindowMetrics = activity.getWindowManager().getMaximumWindowMetrics();

The maximum window metrics are for making calculations, layout choices, or determining the size of resources to fetch ahead of time. Having this available in onCreate() enables you to make these decisions before the first layout pass. These metrics should not be used for laying out specific view elements; instead use information from the Configuration object.

Display cutouts

Foldable devices might have different cutout geometry when folded and unfolded. To avoid cutout issues read Best practices for display cutout support.

Secondary displays

You can get the available displays from the DisplayManager system service:

Kotlin

val displayManager = getSystemService(Context.DISPLAY_SERVICE) as DisplayManager val displays = displayManager.getDisplays()

Java

DisplayManager displayManager = (DisplayManager) getSystemService(Context.DISPLAY_SERVICE); Display[] displays = displayManager.getDisplays();

Use the Display class to get information about a particular display, such as the display size or flags that indicate whether a display is secure. However, do not assume that the display size is going to be the same as the display area allocated to your application. Remember that in multi-window mode, your application occupies a portion of the display.

Determine whether an activity can launch on a display:

Kotlin

val activityManager = getSystemService(Context.ACTIVITY_SERVICE) as ActivityManager val activityAllowed = activityManager.isActivityStartAllowedOnDisplay(context, displayId, intent)

Java

ActivityManager activityManager = (ActivityManager) getSystemService(Context.ACTIVITY_SERVICE); boolean activityAllowed = activityManager.isActivityStartAllowedOnDisplay(context, displayId, intent);

Then launch the activity on the display:

Kotlin

val options = ActivityOptions.makeBasic() options.setLaunchDisplayId(targetDisplay.displayId) startActivity(intent, options.toBundle())

Java

ActivityOptions options = ActivityOptions.makeBasic(); options.setLaunchDisplayId(targetDisplay.displayId); startActivity(intent, options.toBundle());

Multi-display support

Android provides multi-display support for software keyboards, wallpapers, and launchers.

Software keyboard

A keyboard can be shown on a secondary screen if the display is configured to support system decorations. The input method editor automatically appears if a text field requests input on that display.

Keyboard on a secondary display.

Figure 4. Keyboard on a secondary display.

Wallpaper

In Android 10 (API level 29), secondary screens can have wallpaper. The framework creates a separate instance of WallpaperService.Engine for each display. Make sure the surface of each engine is drawn independently. Developers can load assets using the display context in WallpaperService.Engine#getDisplayContext(). Also, make sure your WallpaperInfo.xml file sets android:supportsMultipleDisplays="true".

Wallpaper on phone and secondary display.

Figure 5. Wallpaper on phone and secondary display.

Launchers

A new intent filter category, SECONDARY_HOME, provides a dedicated activity for secondary screens. Instances of the activity are used on all displays that support system decorations, one per each display.

          <activity>     ...     <intent-filter>         <category android:name="android.intent.category.SECONDARY_HOME" />         ...     </intent-filter> </activity>

The activity must have a launch mode that does not prevent multiple instances and that can adapt to different screen sizes. The launch mode cannot be singleInstance or singleTask.

For example, the AOSP implementation of Launcher3 supports a SECONDARY_HOME activity.

Material Design launcher on a phone.

Figure 6. Material Design launcher on a phone.

Material Design launcher on a secondary display.

Figure 7. Material Design launcher on a secondary display.

Window metrics

Android 11 (API level 30) introduced the following WindowManager methods to provide the bounds of apps running in multi-window mode:

getCurrentWindowMetrics(): returns a WindowMetrics object for the current windowing state of the system
getMaximumWindowMetrics(): returns WindowMetrics for the largest potential windowing state of the system

The Jetpack WindowManager library methods computeCurrentWindowMetrics() and computeMaximumWindowMetrics() offer similar functionality respectively, but with backward compatibility to API level 14.

Deprecated methods

Display methods getSize() and getMetrics() were deprecated in API level 30 in favor of the new WindowManager methods.

Android 12 (API level 31) deprecates Display methods getRealSize() and getRealMetrics() and updates their behavior to more closely match the behavior of getMaximumWindowMetrics().

Multi-window mode configuration

If your app targets Android 7.0 (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 android:resizeableActivity="true", then all activities in the task stack are resizable. On some larger devices, such as Chromebooks, your app might run in a resizable window even if you specify android:resizeableActivity="false". If this will break your app, you can use filters to restrict your app's availability on such devices.

Note: 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 not 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.

Android 12 (API level 31) defaults to multi-window mode. On large screens (sw >= 600dp), all apps run in multi-window mode regardless of app configuration. On small screens, the system checks an activity's minWidth, minHeight, and resizeableActivity settings to determine whether the activity can run in multi-window mode.

resizeableActivity

Set this attribute in your manifest's <activity> or <application> element to enable or disable multi-window display for API level 30 and lower:

<application   android:name=".MyActivity"   android:resizeableActivity=["true" | "false"] />

If this attribute is set to true, the activity can be launched in split-screen and free-form 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.

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

If your app targets API level 31 or higher, this attribute works differently on small and large screens:

Large screens (sw >= 600dp): All apps support multi-window mode. The attribute indicates whether an activity can be resized. If resizeableActivity="false", the app is put into compatibility mode when necessary to conform to display dimensions.
Small screens (sw < 600dp): If resizeableActivity="true" and activity minimum width and minimum height are within the multi-window requirements, the activity supports multi-window mode. If resizeableActivity="false", the activity does not support multi-window mode regardless of activity minimum width and height.

supportsPictureInPicture

Set this attribute in your manifest's <activity> node to indicate whether the activity supports picture-in-picture mode.

<activity   android:name=".MyActivity"   android:supportsPictureInPicture=["true" | "false"] />

Note: If supportsPictureInPicture="true", you must set the android:configChanges attribute to enable your activity to handle configuration changes (see Picture-in-picture support).

configChanges

To handle multi-window configuration changes yourself, such as when a user resizes a window, add the android:configChanges attribute to your app manifest <activity> node with at least the following values:

<activity   android:name=".MyActivity"   android:configChanges="screenSize | smallestScreenSize       | screenLayout | orientation" />

After adding android:configChanges, your activity and fragments receive a callback to onConfigurationChanged() instead of being destroyed and recreated. You can then manually update your views, reload resources, and perform other operations as needed.

<layout>

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

android:defaultWidth: Default width of the activity when launched in free-form mode.
android:defaultHeight: Default height of the activity when launched in free-form mode.
android:gravity: Initial placement of the activity when launched in free-form mode. See the Gravity reference for suitable values.
android:minHeight, android:minWidth: Minimum height and minimum width for the activity in both split-screen and free-form 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.

The following code shows how to specify an activity's default size and location and its minimum size when the activity is displayed in free-form mode:

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

Multi-window mode at runtime

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

Disabled features in multi-window mode

Certain features are disabled or ignored when a device is in multi-window mode because they don't make sense for an activity that may be sharing the device screen with other activities or apps.

Some system UI customization options are disabled; for example, apps cannot hide the status bar if they are running in multi-window mode (see Control the system UI visibility).

The system ignores changes to the android:screenOrientation attribute.

Multi-window mode queries and callbacks

The Activity class offers the following methods to support multi-window display:

isInMultiWindowMode(): Indicates whether the activity is in multi-window mode.
isInPictureInPictureMode(): Indicates whether the activity is in picture-in-picture mode.
Note: Picture-in-picture mode is a special case of multi-window mode. If myActivity.isInPictureInPictureMode() returns true, then myActivity.isInMultiWindowMode() also returns true.
onMultiWindowModeChanged(): 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 or false if the activity is leaving multi-window mode.
onPictureInPictureModeChanged(): 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 or false if the activity is leaving picture-in-picture mode.

The Fragment class exposes versions of many of these methods; for example, Fragment.onMultiWindowModeChanged().

Picture-in-picture mode

To put an activity in picture-in-picture mode, call enterPictureInPictureMode() This method has no effect if the device does not support picture-in-picture mode. For more information, see Picture-in-picture support.

New activities in multi-window mode

When you launch a new activity, you can indicate that the new activity should be displayed adjacent to the current one if possible. Use the intent flag FLAG_ACTIVITY_LAUNCH_ADJACENT, which tells the system to try to create the new activity in an adjacent window, so the two activities share the screen. The system makes a best effort to do this, but it is not guaranteed to happen.

If a device is in free-form mode and you are launching a new activity, you can specify the new activity's dimensions and screen location by calling ActivityOptions.setLaunchBounds(). This method has no effect if the device is not in multi-window mode.

On API level 30 and lower, 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.

Android 12 (API level 31) enables apps to split an application's task window among multiple activities. You determine how your app displays its activities — full screen, side by side, or stacked — by creating an XML configuration file or making Jetpack WindowManager API calls.

Drag and drop

Users can drag and drop 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.) To quickly add support for accepting dropped content in editable TextView widgets, see the OnReceiveContentListener interface. For comprehensive drag‑and‑drop support, such as enabling the dragging of content from your app, see Drag and drop.

Important classes and methods for implementing drag and drop include the following:

ClipData: Representation of data on the clipboard. References the data to be transferred by the drag and drop operation.
DragAndDropPermissions: Token object responsible for specifying the permissions granted to the app that receives a drop.
DragAndDropPermissions.release(): Releases the permissions needed to access the data at the content URI given in the ClipData. If you don't call this method, the permissions are released automatically when the containing activity is destroyed.
View.startDragAndDrop(): To enable cross-activity drag and drop, pass the flag DRAG_FLAG_GLOBAL. If you need to give URI permissions to the recipient activity, pass DRAG_FLAG_GLOBAL_URI_READ or DRAG_FLAG_GLOBAL_URI_WRITE.
View.cancelDragAndDrop(): Cancels a drag operation currently in progress. Can only be called by the app that originated the drag operation.
View.updateDragShadow(): Replaces the drag shadow for a drag operation currently in progress. Can only be called by the app that originated the drag operation.
Activity.requestDragAndDropPermissions(): Requests the permissions for the content URIs passed with the ClipData contained in a DragEvent.

Multi-instance

Each root activity has its own task, which runs on a separate process and is displayed in its own window. To launch a new instance of your app in a separate window, you can start new activities with the FLAG_ACTIVITY_NEW_TASK flag. You can combine this with some of the multi-window attributes to request a specific location for the new window. For example, a shopping app can display multiple windows to compare products.

Android 12 (API level 31) enables you to launch two instances of an activity side by side in the same task window.

Don't confuse multi-instance with a multi-panel layout, such as a list/detail layout that uses SlidingPaneLayout, which runs inside a single window.

Note that when multiple instances are running in separate windows on a foldable device, one or more instances might be sent to the background if the posture changes. For example, assume a device is unfolded and has two app instances running in two windows on either side of the fold. If the device is folded, one of the instances might be terminated instead of trying to fit the windows for both instances on a smaller screen.

Multi-window mode verification

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.

Configure a test device

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

If your app targets API level 23 or lower

When users attempt to use the app in multi-window mode, the system forcibly resizes the app unless the app declares a fixed orientation.

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.

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.

If your app targets API levels 24 through 30

If your app targets API levels 24 through 30 and does not disable multi-window support, verify the following behavior under both split-screen and free-form modes:

Launch the app full screen, then switch to multi-window mode by long-pressing the Recents button. Verify that the app switches properly.
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 Recents button, then long-pressing the title bar of your app and dragging it to one of the highlighted areas on the screen.
Resize your app in split-screen mode by dragging the screen divider. Verify that the app resizes without crashing and that necessary UI elements are visible.
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 dimensions.
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.

If your app targets API level 31 or higher

If your app targets API level 31 or higher and the main activity's minimum width and minimum height are less than or equal to the respective dimensions of the available display area, verify all the behaviors listed for API levels 24 through 30.

Note: You can programmatically determine whether your app is in multi-window mode by checking the return value of Activity#isInMultiWindowMode().

Test checklist

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

Enter and leave multi-window mode.
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.
In split-screen mode, try moving the screen divider 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.
Perform several resize operations in rapid succession. Verify that your app doesn't crash or leak memory. Android Studio's Memory Profiler provides information about your app's memory usage (see Inspect your app's memory usage with Memory Profiler).
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.

If you have disabled multi-window support

On API levels 24 through 30, if you disabled multi-window support by setting android:resizeableActivity="false", you should launch your app on a device running Android 7.0 through 11 and attempt to put the app in split-screen and free-form modes. Verify that when you do so, the app remains in full-screen mode.

Additional resources

For further information about multi-window support in Android, see:

5 tips for preparing for multi-window in Android N
Android MultiWindowPlayground sample