Merge changes Id1c3e56e,Id14bfaed,I3aae76de,I46ff1214,I58a7f648 into udc-qpr-dev am: 3400bb34d5 am: 1a61272e99

Original change: https://googleplex-android-review.googlesource.com/c/platform/frameworks/base/+/23781543

Change-Id: I0729f5e48085e143249f9831cfece40659dbe9d4
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>

23 files changed, 1436 insertions, 0 deletions

diff --git a/packages/SystemUI/src/com/android/systemui/dagger/SystemUICoreStartableModule.kt b/packages/SystemUI/src/com/android/systemui/dagger/SystemUICoreStartableModule.kt
index 40db63d609ba..b1f513d0945c 100644
--- a/packages/SystemUI/src/com/android/systemui/dagger/SystemUICoreStartableModule.kt
+++ b/packages/SystemUI/src/com/android/systemui/dagger/SystemUICoreStartableModule.kt
@@ -42,6 +42,7 @@ import com.android.systemui.media.dialog.MediaOutputSwitcherDialogUI
 import com.android.systemui.media.taptotransfer.MediaTttCommandLineHelper
 import com.android.systemui.media.taptotransfer.receiver.MediaTttChipControllerReceiver
 import com.android.systemui.media.taptotransfer.sender.MediaTttSenderCoordinator
+import com.android.systemui.mediaprojection.taskswitcher.MediaProjectionTaskSwitcherCoreStartable
 import com.android.systemui.power.PowerUI
 import com.android.systemui.reardisplay.RearDisplayDialogController
 import com.android.systemui.recents.Recents
@@ -111,6 +112,14 @@ abstract class SystemUICoreStartableModule {
     @ClassKey(KeyboardUI::class)
     abstract fun bindKeyboardUI(sysui: KeyboardUI): CoreStartable
 
+    /** Inject into MediaProjectionTaskSwitcherCoreStartable. */
+    @Binds
+    @IntoMap
+    @ClassKey(MediaProjectionTaskSwitcherCoreStartable::class)
+    abstract fun bindProjectedTaskListener(
+            sysui: MediaProjectionTaskSwitcherCoreStartable
+    ): CoreStartable
+
     /** Inject into KeyguardBiometricLockoutLogger */
     @Binds
     @IntoMap
diff --git a/packages/SystemUI/src/com/android/systemui/dagger/SystemUIModule.java b/packages/SystemUI/src/com/android/systemui/dagger/SystemUIModule.java
index 06769dc3f831..eef850821166 100644
--- a/packages/SystemUI/src/com/android/systemui/dagger/SystemUIModule.java
+++ b/packages/SystemUI/src/com/android/systemui/dagger/SystemUIModule.java
@@ -58,6 +58,7 @@ import com.android.systemui.log.dagger.LogModule;
 import com.android.systemui.log.dagger.MonitorLog;
 import com.android.systemui.log.table.TableLogBuffer;
 import com.android.systemui.mediaprojection.appselector.MediaProjectionModule;
+import com.android.systemui.mediaprojection.taskswitcher.MediaProjectionTaskSwitcherModule;
 import com.android.systemui.model.SysUiState;
 import com.android.systemui.motiontool.MotionToolModule;
 import com.android.systemui.navigationbar.NavigationBarComponent;
@@ -181,6 +182,7 @@ import javax.inject.Named;
             LockscreenLayoutModule.class,
             LogModule.class,
             MediaProjectionModule.class,
+            MediaProjectionTaskSwitcherModule.class,
             MotionToolModule.class,
             PeopleHubModule.class,
             PeopleModule.class,
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherCoreStartable.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherCoreStartable.kt
new file mode 100644
index 000000000000..3c501277ab8c
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherCoreStartable.kt
@@ -0,0 +1,39 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher
+
+import com.android.systemui.CoreStartable
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.flags.FeatureFlags
+import com.android.systemui.flags.Flags
+import com.android.systemui.mediaprojection.taskswitcher.ui.TaskSwitcherNotificationCoordinator
+import javax.inject.Inject
+
+@SysUISingleton
+class MediaProjectionTaskSwitcherCoreStartable
+@Inject
+constructor(
+    private val notificationCoordinator: TaskSwitcherNotificationCoordinator,
+    private val featureFlags: FeatureFlags,
+) : CoreStartable {
+
+    override fun start() {
+        if (featureFlags.isEnabled(Flags.PARTIAL_SCREEN_SHARING_TASK_SWITCHER)) {
+            notificationCoordinator.start()
+        }
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherModule.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherModule.kt
new file mode 100644
index 000000000000..22ad07ebc3b1
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherModule.kt
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher
+
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.ActivityTaskManagerTasksRepository
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.MediaProjectionManagerRepository
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.MediaProjectionRepository
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.TasksRepository
+import dagger.Binds
+import dagger.Module
+
+@Module
+interface MediaProjectionTaskSwitcherModule {
+
+    @Binds fun mediaRepository(impl: MediaProjectionManagerRepository): MediaProjectionRepository
+
+    @Binds fun tasksRepository(impl: ActivityTaskManagerTasksRepository): TasksRepository
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/model/MediaProjectionState.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/model/MediaProjectionState.kt
new file mode 100644
index 000000000000..9938f11e5d4c
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/model/MediaProjectionState.kt
@@ -0,0 +1,26 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.model
+
+import android.app.TaskInfo
+
+/** Represents the state of media projection. */
+sealed interface MediaProjectionState {
+    object NotProjecting : MediaProjectionState
+    object EntireScreen : MediaProjectionState
+    data class SingleTask(val task: TaskInfo) : MediaProjectionState
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/ActivityTaskManagerTasksRepository.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/ActivityTaskManagerTasksRepository.kt
new file mode 100644
index 000000000000..492d482459d6
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/ActivityTaskManagerTasksRepository.kt
@@ -0,0 +1,75 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.app.ActivityManager.RunningTaskInfo
+import android.app.ActivityTaskManager
+import android.app.TaskStackListener
+import android.os.IBinder
+import android.util.Log
+import com.android.systemui.common.coroutine.ChannelExt.trySendWithFailureLogging
+import com.android.systemui.common.coroutine.ConflatedCallbackFlow.conflatedCallbackFlow
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.dagger.qualifiers.Application
+import com.android.systemui.dagger.qualifiers.Background
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.shareIn
+import kotlinx.coroutines.withContext
+
+/** Implementation of [TasksRepository] that uses [ActivityTaskManager] as the data source. */
+@SysUISingleton
+class ActivityTaskManagerTasksRepository
+@Inject
+constructor(
+    private val activityTaskManager: ActivityTaskManager,
+    @Application private val applicationScope: CoroutineScope,
+    @Background private val backgroundDispatcher: CoroutineDispatcher,
+) : TasksRepository {
+
+    override suspend fun findRunningTaskFromWindowContainerToken(
+        windowContainerToken: IBinder
+    ): RunningTaskInfo? =
+        getRunningTasks().firstOrNull { taskInfo ->
+            taskInfo.token.asBinder() == windowContainerToken
+        }
+
+    private suspend fun getRunningTasks(): List<RunningTaskInfo> =
+        withContext(backgroundDispatcher) { activityTaskManager.getTasks(Integer.MAX_VALUE) }
+
+    override val foregroundTask: Flow<RunningTaskInfo> =
+        conflatedCallbackFlow {
+                val listener =
+                    object : TaskStackListener() {
+                        override fun onTaskMovedToFront(taskInfo: RunningTaskInfo) {
+                            Log.d(TAG, "onTaskMovedToFront: $taskInfo")
+                            trySendWithFailureLogging(taskInfo, TAG)
+                        }
+                    }
+                activityTaskManager.registerTaskStackListener(listener)
+                awaitClose { activityTaskManager.unregisterTaskStackListener(listener) }
+            }
+            .shareIn(applicationScope, SharingStarted.Lazily, replay = 1)
+
+    companion object {
+        private const val TAG = "TasksRepository"
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepository.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepository.kt
new file mode 100644
index 000000000000..38d4e698f2d9
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepository.kt
@@ -0,0 +1,92 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.media.projection.MediaProjectionInfo
+import android.media.projection.MediaProjectionManager
+import android.os.Handler
+import android.util.Log
+import android.view.ContentRecordingSession
+import android.view.ContentRecordingSession.RECORD_CONTENT_DISPLAY
+import com.android.systemui.common.coroutine.ChannelExt.trySendWithFailureLogging
+import com.android.systemui.common.coroutine.ConflatedCallbackFlow.conflatedCallbackFlow
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.dagger.qualifiers.Application
+import com.android.systemui.dagger.qualifiers.Main
+import com.android.systemui.mediaprojection.taskswitcher.data.model.MediaProjectionState
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.shareIn
+import kotlinx.coroutines.launch
+
+@SysUISingleton
+class MediaProjectionManagerRepository
+@Inject
+constructor(
+    private val mediaProjectionManager: MediaProjectionManager,
+    @Main private val handler: Handler,
+    @Application private val applicationScope: CoroutineScope,
+    private val tasksRepository: TasksRepository,
+) : MediaProjectionRepository {
+
+    override val mediaProjectionState: Flow<MediaProjectionState> =
+        conflatedCallbackFlow {
+                val callback =
+                    object : MediaProjectionManager.Callback() {
+                        override fun onStart(info: MediaProjectionInfo?) {
+                            Log.d(TAG, "MediaProjectionManager.Callback#onStart")
+                            trySendWithFailureLogging(MediaProjectionState.NotProjecting, TAG)
+                        }
+
+                        override fun onStop(info: MediaProjectionInfo?) {
+                            Log.d(TAG, "MediaProjectionManager.Callback#onStop")
+                            trySendWithFailureLogging(MediaProjectionState.NotProjecting, TAG)
+                        }
+
+                        override fun onRecordingSessionSet(
+                            info: MediaProjectionInfo,
+                            session: ContentRecordingSession?
+                        ) {
+                            Log.d(TAG, "MediaProjectionManager.Callback#onSessionStarted: $session")
+                            launch { trySendWithFailureLogging(stateForSession(session), TAG) }
+                        }
+                    }
+                mediaProjectionManager.addCallback(callback, handler)
+                awaitClose { mediaProjectionManager.removeCallback(callback) }
+            }
+            .shareIn(scope = applicationScope, started = SharingStarted.Lazily, replay = 1)
+
+    private suspend fun stateForSession(session: ContentRecordingSession?): MediaProjectionState {
+        if (session == null) {
+            return MediaProjectionState.NotProjecting
+        }
+        if (session.contentToRecord == RECORD_CONTENT_DISPLAY || session.tokenToRecord == null) {
+            return MediaProjectionState.EntireScreen
+        }
+        val matchingTask =
+            tasksRepository.findRunningTaskFromWindowContainerToken(session.tokenToRecord)
+                ?: return MediaProjectionState.EntireScreen
+        return MediaProjectionState.SingleTask(matchingTask)
+    }
+
+    companion object {
+        private const val TAG = "MediaProjectionMngrRepo"
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionRepository.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionRepository.kt
new file mode 100644
index 000000000000..5bec6925babe
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionRepository.kt
@@ -0,0 +1,27 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import com.android.systemui.mediaprojection.taskswitcher.data.model.MediaProjectionState
+import kotlinx.coroutines.flow.Flow
+
+/** Represents a repository to retrieve and change data related to media projection. */
+interface MediaProjectionRepository {
+
+    /** Represents the current [MediaProjectionState]. */
+    val mediaProjectionState: Flow<MediaProjectionState>
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/NoOpMediaProjectionRepository.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/NoOpMediaProjectionRepository.kt
new file mode 100644
index 000000000000..544eb6b99d4f
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/NoOpMediaProjectionRepository.kt
@@ -0,0 +1,33 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.mediaprojection.taskswitcher.data.model.MediaProjectionState
+import javax.inject.Inject
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.emptyFlow
+
+/**
+ * No-op implementation of [MediaProjectionRepository] that does nothing. Currently used as a
+ * placeholder, while the real implementation is not completed.
+ */
+@SysUISingleton
+class NoOpMediaProjectionRepository @Inject constructor() : MediaProjectionRepository {
+
+    override val mediaProjectionState: Flow<MediaProjectionState> = emptyFlow()
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/TasksRepository.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/TasksRepository.kt
new file mode 100644
index 000000000000..6a535e4ecc50
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/TasksRepository.kt
@@ -0,0 +1,41 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.app.ActivityManager.RunningTaskInfo
+import android.os.IBinder
+import kotlinx.coroutines.flow.Flow
+
+/** Repository responsible for retrieving data related to running tasks. */
+interface TasksRepository {
+
+    /**
+     * Tries to find a [RunningTaskInfo] with a matching window container token. Returns `null` when
+     * no matching task was found.
+     */
+    suspend fun findRunningTaskFromWindowContainerToken(
+        windowContainerToken: IBinder
+    ): RunningTaskInfo?
+
+    /**
+     * Emits a stream of [RunningTaskInfo] that have been moved to the foreground.
+     *
+     * Note: when subscribing for the first time, it will not immediately emit the current
+     * foreground task. Only after a change in foreground task has occurred.
+     */
+    val foregroundTask: Flow<RunningTaskInfo>
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/domain/interactor/TaskSwitchInteractor.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/domain/interactor/TaskSwitchInteractor.kt
new file mode 100644
index 000000000000..fc5cf7d75bdf
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/domain/interactor/TaskSwitchInteractor.kt
@@ -0,0 +1,85 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.domain.interactor
+
+import android.app.TaskInfo
+import android.content.Intent
+import android.util.Log
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.mediaprojection.taskswitcher.data.model.MediaProjectionState
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.MediaProjectionRepository
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.TasksRepository
+import com.android.systemui.mediaprojection.taskswitcher.domain.model.TaskSwitchState
+import javax.inject.Inject
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.flatMapLatest
+import kotlinx.coroutines.flow.flowOf
+import kotlinx.coroutines.flow.map
+
+/** Interactor with logic related to task switching in the context of media projection. */
+@OptIn(ExperimentalCoroutinesApi::class)
+@SysUISingleton
+class TaskSwitchInteractor
+@Inject
+constructor(
+    mediaProjectionRepository: MediaProjectionRepository,
+    private val tasksRepository: TasksRepository,
+) {
+
+    /**
+     * Emits a stream of changes to the state of task switching, in the context of media projection.
+     */
+    val taskSwitchChanges: Flow<TaskSwitchState> =
+        mediaProjectionRepository.mediaProjectionState.flatMapLatest { projectionState ->
+            Log.d(TAG, "MediaProjectionState -> $projectionState")
+            when (projectionState) {
+                is MediaProjectionState.SingleTask -> {
+                    val projectedTask = projectionState.task
+                    tasksRepository.foregroundTask.map { foregroundTask ->
+                        if (hasForegroundTaskSwitched(projectedTask, foregroundTask)) {
+                            TaskSwitchState.TaskSwitched(projectedTask, foregroundTask)
+                        } else {
+                            TaskSwitchState.TaskUnchanged
+                        }
+                    }
+                }
+                is MediaProjectionState.EntireScreen,
+                is MediaProjectionState.NotProjecting -> {
+                    flowOf(TaskSwitchState.NotProjectingTask)
+                }
+            }
+        }
+
+    /**
+     * Returns whether tasks have been switched.
+     *
+     * Always returns `false` when launcher is in the foreground. The reason is that when going to
+     * recents to switch apps, launcher becomes the new foreground task, and we don't want to show
+     * the notification then.
+     */
+    private fun hasForegroundTaskSwitched(projectedTask: TaskInfo, foregroundTask: TaskInfo) =
+        projectedTask.taskId != foregroundTask.taskId && !foregroundTask.isLauncher
+
+    private val TaskInfo.isLauncher
+        get() =
+            baseIntent.hasCategory(Intent.CATEGORY_HOME) && baseIntent.action == Intent.ACTION_MAIN
+
+    companion object {
+        private const val TAG = "TaskSwitchInteractor"
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/domain/model/TaskSwitchState.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/domain/model/TaskSwitchState.kt
new file mode 100644
index 000000000000..cd1258ed6aa8
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/domain/model/TaskSwitchState.kt
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.domain.model
+
+import android.app.TaskInfo
+
+/** Represents tha state of task switching in the context of single task media projection. */
+sealed interface TaskSwitchState {
+    /** Currently no task is being projected. */
+    object NotProjectingTask : TaskSwitchState
+    /** The foreground task is the same as the task that is currently being projected. */
+    object TaskUnchanged : TaskSwitchState
+    /** The foreground task is a different one to the task it currently being projected. */
+    data class TaskSwitched(val projectedTask: TaskInfo, val foregroundTask: TaskInfo) :
+        TaskSwitchState
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/TaskSwitcherNotificationCoordinator.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/TaskSwitcherNotificationCoordinator.kt
new file mode 100644
index 000000000000..a4f407612fa8
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/TaskSwitcherNotificationCoordinator.kt
@@ -0,0 +1,74 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.ui
+
+import android.content.Context
+import android.util.Log
+import android.widget.Toast
+import com.android.systemui.dagger.SysUISingleton
+import com.android.systemui.dagger.qualifiers.Application
+import com.android.systemui.dagger.qualifiers.Main
+import com.android.systemui.mediaprojection.taskswitcher.ui.model.TaskSwitcherNotificationUiState.NotShowing
+import com.android.systemui.mediaprojection.taskswitcher.ui.model.TaskSwitcherNotificationUiState.Showing
+import com.android.systemui.mediaprojection.taskswitcher.ui.viewmodel.TaskSwitcherNotificationViewModel
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineDispatcher
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.flow.flowOn
+import kotlinx.coroutines.launch
+
+/** Coordinator responsible for showing/hiding the task switcher notification. */
+@SysUISingleton
+class TaskSwitcherNotificationCoordinator
+@Inject
+constructor(
+    private val context: Context,
+    @Application private val applicationScope: CoroutineScope,
+    @Main private val mainDispatcher: CoroutineDispatcher,
+    private val viewModel: TaskSwitcherNotificationViewModel,
+) {
+
+    fun start() {
+        applicationScope.launch {
+            viewModel.uiState.flowOn(mainDispatcher).collect { uiState ->
+                Log.d(TAG, "uiState -> $uiState")
+                when (uiState) {
+                    is Showing -> showNotification(uiState)
+                    is NotShowing -> hideNotification()
+                }
+            }
+        }
+    }
+
+    private fun showNotification(uiState: Showing) {
+        val text =
+            """
+            Sharing pauses when you switch apps.
+            Share this app instead.
+            Switch back.
+            """
+                .trimIndent()
+        // TODO(b/286201515): Create actual notification.
+        Toast.makeText(context, text, Toast.LENGTH_SHORT).show()
+    }
+
+    private fun hideNotification() {}
+
+    companion object {
+        private const val TAG = "TaskSwitchNotifCoord"
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/model/TaskSwitcherNotificationUiState.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/model/TaskSwitcherNotificationUiState.kt
new file mode 100644
index 000000000000..21aee72d17ae
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/model/TaskSwitcherNotificationUiState.kt
@@ -0,0 +1,30 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.ui.model
+
+import android.app.TaskInfo
+
+/** Represents the UI state for the task switcher notification. */
+sealed interface TaskSwitcherNotificationUiState {
+    /** The notification should not be shown. */
+    object NotShowing : TaskSwitcherNotificationUiState
+    /** The notification should be shown. */
+    data class Showing(
+        val projectedTask: TaskInfo,
+        val foregroundTask: TaskInfo,
+    ) : TaskSwitcherNotificationUiState
+}
diff --git a/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/viewmodel/TaskSwitcherNotificationViewModel.kt b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/viewmodel/TaskSwitcherNotificationViewModel.kt
new file mode 100644
index 000000000000..d9754d4429d4
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/mediaprojection/taskswitcher/ui/viewmodel/TaskSwitcherNotificationViewModel.kt
@@ -0,0 +1,49 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.ui.viewmodel
+
+import android.util.Log
+import com.android.systemui.mediaprojection.taskswitcher.domain.interactor.TaskSwitchInteractor
+import com.android.systemui.mediaprojection.taskswitcher.domain.model.TaskSwitchState
+import com.android.systemui.mediaprojection.taskswitcher.ui.model.TaskSwitcherNotificationUiState
+import javax.inject.Inject
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.map
+
+class TaskSwitcherNotificationViewModel @Inject constructor(interactor: TaskSwitchInteractor) {
+
+    val uiState: Flow<TaskSwitcherNotificationUiState> =
+        interactor.taskSwitchChanges.map { taskSwitchChange ->
+            Log.d(TAG, "taskSwitchChange: $taskSwitchChange")
+            when (taskSwitchChange) {
+                is TaskSwitchState.TaskSwitched -> {
+                    TaskSwitcherNotificationUiState.Showing(
+                        projectedTask = taskSwitchChange.projectedTask,
+                        foregroundTask = taskSwitchChange.foregroundTask,
+                    )
+                }
+                is TaskSwitchState.NotProjectingTask,
+                is TaskSwitchState.TaskUnchanged -> {
+                    TaskSwitcherNotificationUiState.NotShowing
+                }
+            }
+        }
+
+    companion object {
+        private const val TAG = "TaskSwitchNotifVM"
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherCoreStartableTest.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherCoreStartableTest.kt
new file mode 100644
index 000000000000..bcbf666fd302
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/MediaProjectionTaskSwitcherCoreStartableTest.kt
@@ -0,0 +1,67 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher
+
+import android.testing.AndroidTestingRunner
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.flags.FeatureFlags
+import com.android.systemui.flags.Flags
+import com.android.systemui.mediaprojection.taskswitcher.ui.TaskSwitcherNotificationCoordinator
+import com.android.systemui.util.mockito.whenever
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+import org.mockito.Mock
+import org.mockito.Mockito.verify
+import org.mockito.Mockito.verifyZeroInteractions
+import org.mockito.MockitoAnnotations
+
+@RunWith(AndroidTestingRunner::class)
+@SmallTest
+class MediaProjectionTaskSwitcherCoreStartableTest : SysuiTestCase() {
+
+    @Mock private lateinit var flags: FeatureFlags
+    @Mock private lateinit var coordinator: TaskSwitcherNotificationCoordinator
+
+    private lateinit var coreStartable: MediaProjectionTaskSwitcherCoreStartable
+
+    @Before
+    fun setUp() {
+        MockitoAnnotations.initMocks(this)
+
+        coreStartable = MediaProjectionTaskSwitcherCoreStartable(coordinator, flags)
+    }
+
+    @Test
+    fun start_flagEnabled_startsCoordinator() {
+        whenever(flags.isEnabled(Flags.PARTIAL_SCREEN_SHARING_TASK_SWITCHER)).thenReturn(true)
+
+        coreStartable.start()
+
+        verify(coordinator).start()
+    }
+
+    @Test
+    fun start_flagDisabled_doesNotStartCoordinator() {
+        whenever(flags.isEnabled(Flags.PARTIAL_SCREEN_SHARING_TASK_SWITCHER)).thenReturn(false)
+
+        coreStartable.start()
+
+        verifyZeroInteractions(coordinator)
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/ActivityTaskManagerTasksRepositoryTest.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/ActivityTaskManagerTasksRepositoryTest.kt
new file mode 100644
index 000000000000..83932b0a6133
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/ActivityTaskManagerTasksRepositoryTest.kt
@@ -0,0 +1,108 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.os.Binder
+import android.testing.AndroidTestingRunner
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.coroutines.collectLastValue
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeActivityTaskManager.Companion.createTask
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeActivityTaskManager.Companion.createToken
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@OptIn(ExperimentalCoroutinesApi::class)
+@RunWith(AndroidTestingRunner::class)
+@SmallTest
+class ActivityTaskManagerTasksRepositoryTest : SysuiTestCase() {
+
+    private val fakeActivityTaskManager = FakeActivityTaskManager()
+
+    private val dispatcher = UnconfinedTestDispatcher()
+    private val testScope = TestScope(dispatcher)
+
+    private val repo =
+        ActivityTaskManagerTasksRepository(
+            activityTaskManager = fakeActivityTaskManager.activityTaskManager,
+            applicationScope = testScope.backgroundScope,
+            backgroundDispatcher = dispatcher
+        )
+
+    @Test
+    fun findRunningTaskFromWindowContainerToken_noMatch_returnsNull() {
+        fakeActivityTaskManager.addRunningTasks(createTask(taskId = 1), createTask(taskId = 2))
+
+        testScope.runTest {
+            val matchingTask =
+                repo.findRunningTaskFromWindowContainerToken(windowContainerToken = Binder())
+
+            assertThat(matchingTask).isNull()
+        }
+    }
+
+    @Test
+    fun findRunningTaskFromWindowContainerToken_matchingToken_returnsTaskInfo() {
+        val expectedToken = createToken()
+        val expectedTask = createTask(taskId = 1, token = expectedToken)
+
+        fakeActivityTaskManager.addRunningTasks(
+            createTask(taskId = 2),
+            expectedTask,
+        )
+
+        testScope.runTest {
+            val actualTask =
+                repo.findRunningTaskFromWindowContainerToken(
+                    windowContainerToken = expectedToken.asBinder()
+                )
+
+            assertThat(actualTask).isEqualTo(expectedTask)
+        }
+    }
+
+    @Test
+    fun foregroundTask_returnsStreamOfTasksMovedToFront() =
+        testScope.runTest {
+            val foregroundTask by collectLastValue(repo.foregroundTask)
+
+            fakeActivityTaskManager.moveTaskToForeground(createTask(taskId = 1))
+            assertThat(foregroundTask?.taskId).isEqualTo(1)
+
+            fakeActivityTaskManager.moveTaskToForeground(createTask(taskId = 2))
+            assertThat(foregroundTask?.taskId).isEqualTo(2)
+
+            fakeActivityTaskManager.moveTaskToForeground(createTask(taskId = 3))
+            assertThat(foregroundTask?.taskId).isEqualTo(3)
+        }
+
+    @Test
+    fun foregroundTask_lastValueIsCached() =
+        testScope.runTest {
+            val foregroundTaskA by collectLastValue(repo.foregroundTask)
+            fakeActivityTaskManager.moveTaskToForeground(createTask(taskId = 1))
+            assertThat(foregroundTaskA?.taskId).isEqualTo(1)
+
+            val foregroundTaskB by collectLastValue(repo.foregroundTask)
+            assertThat(foregroundTaskB?.taskId).isEqualTo(1)
+        }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeActivityTaskManager.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeActivityTaskManager.kt
new file mode 100644
index 000000000000..1c4870bc32b1
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeActivityTaskManager.kt
@@ -0,0 +1,77 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.app.ActivityManager.RunningTaskInfo
+import android.app.ActivityTaskManager
+import android.app.TaskStackListener
+import android.content.Intent
+import android.window.IWindowContainerToken
+import android.window.WindowContainerToken
+import com.android.systemui.util.mockito.any
+import com.android.systemui.util.mockito.mock
+import com.android.systemui.util.mockito.whenever
+
+class FakeActivityTaskManager {
+
+    private val runningTasks = mutableListOf<RunningTaskInfo>()
+    private val taskTaskListeners = mutableListOf<TaskStackListener>()
+
+    val activityTaskManager = mock<ActivityTaskManager>()
+
+    init {
+        whenever(activityTaskManager.registerTaskStackListener(any())).thenAnswer {
+            taskTaskListeners += it.arguments[0] as TaskStackListener
+            return@thenAnswer Unit
+        }
+        whenever(activityTaskManager.unregisterTaskStackListener(any())).thenAnswer {
+            taskTaskListeners -= it.arguments[0] as TaskStackListener
+            return@thenAnswer Unit
+        }
+        whenever(activityTaskManager.getTasks(any())).thenAnswer {
+            val maxNumTasks = it.arguments[0] as Int
+            return@thenAnswer runningTasks.take(maxNumTasks)
+        }
+    }
+
+    fun moveTaskToForeground(task: RunningTaskInfo) {
+        taskTaskListeners.forEach { it.onTaskMovedToFront(task) }
+    }
+
+    fun addRunningTasks(vararg tasks: RunningTaskInfo) {
+        runningTasks += tasks
+    }
+
+    companion object {
+
+        fun createTask(
+            taskId: Int,
+            token: WindowContainerToken = createToken(),
+            baseIntent: Intent = Intent()
+        ) =
+            RunningTaskInfo().apply {
+                this.taskId = taskId
+                this.token = token
+                this.baseIntent = baseIntent
+            }
+
+        fun createToken(): WindowContainerToken {
+            val realToken = object : IWindowContainerToken.Stub() {}
+            return WindowContainerToken(realToken)
+        }
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeMediaProjectionRepository.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeMediaProjectionRepository.kt
new file mode 100644
index 000000000000..c59fd60cca9b
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeMediaProjectionRepository.kt
@@ -0,0 +1,42 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.app.TaskInfo
+import com.android.systemui.mediaprojection.taskswitcher.data.model.MediaProjectionState
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+class FakeMediaProjectionRepository : MediaProjectionRepository {
+
+    private val state = MutableStateFlow<MediaProjectionState>(MediaProjectionState.NotProjecting)
+
+    fun switchProjectedTask(newTask: TaskInfo) {
+        state.value = MediaProjectionState.SingleTask(newTask)
+    }
+
+    override val mediaProjectionState: Flow<MediaProjectionState> = state.asStateFlow()
+
+    fun projectEntireScreen() {
+        state.value = MediaProjectionState.EntireScreen
+    }
+
+    fun stopProjecting() {
+        state.value = MediaProjectionState.NotProjecting
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeTasksRepository.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeTasksRepository.kt
new file mode 100644
index 000000000000..593e3893fb2a
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/FakeTasksRepository.kt
@@ -0,0 +1,68 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.app.ActivityManager.RunningTaskInfo
+import android.content.Intent
+import android.os.IBinder
+import android.window.IWindowContainerToken
+import android.window.WindowContainerToken
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.MutableStateFlow
+import kotlinx.coroutines.flow.asStateFlow
+
+class FakeTasksRepository : TasksRepository {
+
+    private val _foregroundTask = MutableStateFlow(DEFAULT_TASK)
+
+    override val foregroundTask: Flow<RunningTaskInfo> = _foregroundTask.asStateFlow()
+
+    private val runningTasks = mutableListOf(DEFAULT_TASK)
+
+    override suspend fun findRunningTaskFromWindowContainerToken(
+        windowContainerToken: IBinder
+    ): RunningTaskInfo? = runningTasks.firstOrNull { it.token.asBinder() == windowContainerToken }
+
+    fun addRunningTask(task: RunningTaskInfo) {
+        runningTasks.add(task)
+    }
+
+    fun moveTaskToForeground(task: RunningTaskInfo) {
+        _foregroundTask.value = task
+    }
+
+    companion object {
+        val DEFAULT_TASK = createTask(taskId = -1)
+        val LAUNCHER_INTENT: Intent = Intent(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_HOME)
+
+        fun createTask(
+            taskId: Int,
+            token: WindowContainerToken = createToken(),
+            baseIntent: Intent = Intent()
+        ) =
+            RunningTaskInfo().apply {
+                this.taskId = taskId
+                this.token = token
+                this.baseIntent = baseIntent
+            }
+
+        fun createToken(): WindowContainerToken {
+            val realToken = object : IWindowContainerToken.Stub() {}
+            return WindowContainerToken(realToken)
+        }
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepositoryTest.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepositoryTest.kt
new file mode 100644
index 000000000000..2b074655bb02
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/data/repository/MediaProjectionManagerRepositoryTest.kt
@@ -0,0 +1,162 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.data.repository
+
+import android.media.projection.MediaProjectionInfo
+import android.media.projection.MediaProjectionManager
+import android.os.Binder
+import android.os.Handler
+import android.os.UserHandle
+import android.testing.AndroidTestingRunner
+import android.view.ContentRecordingSession
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.coroutines.collectLastValue
+import com.android.systemui.mediaprojection.taskswitcher.data.model.MediaProjectionState
+import com.android.systemui.util.mockito.any
+import com.android.systemui.util.mockito.mock
+import com.android.systemui.util.mockito.whenever
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.runCurrent
+import kotlinx.coroutines.test.runTest
+import org.junit.Before
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@OptIn(ExperimentalCoroutinesApi::class)
+@RunWith(AndroidTestingRunner::class)
+@SmallTest
+class MediaProjectionManagerRepositoryTest : SysuiTestCase() {
+
+    private val mediaProjectionManager = mock<MediaProjectionManager>()
+
+    private val dispatcher = StandardTestDispatcher()
+    private val testScope = TestScope(dispatcher)
+    private val tasksRepo = FakeTasksRepository()
+
+    private lateinit var callback: MediaProjectionManager.Callback
+    private lateinit var repo: MediaProjectionManagerRepository
+
+    @Before
+    fun setUp() {
+        whenever(mediaProjectionManager.addCallback(any(), any())).thenAnswer {
+            callback = it.arguments[0] as MediaProjectionManager.Callback
+            return@thenAnswer Unit
+        }
+        repo =
+            MediaProjectionManagerRepository(
+                mediaProjectionManager = mediaProjectionManager,
+                handler = Handler.getMain(),
+                applicationScope = testScope.backgroundScope,
+                tasksRepository = tasksRepo
+            )
+    }
+
+    @Test
+    fun mediaProjectionState_onStart_emitsNotProjecting() =
+        testScope.runTest {
+            val state by collectLastValue(repo.mediaProjectionState)
+            runCurrent()
+
+            callback.onStart(TEST_MEDIA_INFO)
+
+            assertThat(state).isEqualTo(MediaProjectionState.NotProjecting)
+        }
+
+    @Test
+    fun mediaProjectionState_onStop_emitsNotProjecting() =
+        testScope.runTest {
+            val state by collectLastValue(repo.mediaProjectionState)
+            runCurrent()
+
+            callback.onStop(TEST_MEDIA_INFO)
+
+            assertThat(state).isEqualTo(MediaProjectionState.NotProjecting)
+        }
+
+    @Test
+    fun mediaProjectionState_onSessionSet_sessionNull_emitsNotProjecting() =
+        testScope.runTest {
+            val state by collectLastValue(repo.mediaProjectionState)
+            runCurrent()
+
+            callback.onRecordingSessionSet(TEST_MEDIA_INFO, /* session= */ null)
+
+            assertThat(state).isEqualTo(MediaProjectionState.NotProjecting)
+        }
+
+    @Test
+    fun mediaProjectionState_onSessionSet_contentToRecordDisplay_emitsEntireScreen() =
+        testScope.runTest {
+            val state by collectLastValue(repo.mediaProjectionState)
+            runCurrent()
+
+            val session = ContentRecordingSession.createDisplaySession(/* displayToMirror= */ 123)
+            callback.onRecordingSessionSet(TEST_MEDIA_INFO, session)
+
+            assertThat(state).isEqualTo(MediaProjectionState.EntireScreen)
+        }
+
+    @Test
+    fun mediaProjectionState_onSessionSet_tokenNull_emitsEntireScreen() =
+        testScope.runTest {
+            val state by collectLastValue(repo.mediaProjectionState)
+            runCurrent()
+
+            val session =
+                ContentRecordingSession.createTaskSession(/* taskWindowContainerToken= */ null)
+            callback.onRecordingSessionSet(TEST_MEDIA_INFO, session)
+
+            assertThat(state).isEqualTo(MediaProjectionState.EntireScreen)
+        }
+
+    @Test
+    fun mediaProjectionState_sessionSet_taskWithToken_noMatchingRunningTask_emitsEntireScreen() =
+        testScope.runTest {
+            val state by collectLastValue(repo.mediaProjectionState)
+            runCurrent()
+
+            val taskWindowContainerToken = Binder()
+            val session = ContentRecordingSession.createTaskSession(taskWindowContainerToken)
+            callback.onRecordingSessionSet(TEST_MEDIA_INFO, session)
+
+            assertThat(state).isEqualTo(MediaProjectionState.EntireScreen)
+        }
+
+    @Test
+    fun mediaProjectionState_sessionSet_taskWithToken_matchingRunningTask_emitsSingleTask() =
+        testScope.runTest {
+            val token = FakeTasksRepository.createToken()
+            val task = FakeTasksRepository.createTask(taskId = 1, token = token)
+            tasksRepo.addRunningTask(task)
+            val state by collectLastValue(repo.mediaProjectionState)
+            runCurrent()
+
+            val session = ContentRecordingSession.createTaskSession(token.asBinder())
+            callback.onRecordingSessionSet(TEST_MEDIA_INFO, session)
+
+            assertThat(state).isEqualTo(MediaProjectionState.SingleTask(task))
+        }
+
+    companion object {
+        val TEST_MEDIA_INFO =
+            MediaProjectionInfo(/* packageName= */ "com.test.package", UserHandle.CURRENT)
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/domain/interactor/TaskSwitchInteractorTest.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/domain/interactor/TaskSwitchInteractorTest.kt
new file mode 100644
index 000000000000..112950b860e8
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/domain/interactor/TaskSwitchInteractorTest.kt
@@ -0,0 +1,127 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.domain.interactor
+
+import android.content.Intent
+import android.testing.AndroidTestingRunner
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.coroutines.collectLastValue
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.ActivityTaskManagerTasksRepository
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeActivityTaskManager
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeActivityTaskManager.Companion.createTask
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeMediaProjectionRepository
+import com.android.systemui.mediaprojection.taskswitcher.domain.model.TaskSwitchState
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@OptIn(ExperimentalCoroutinesApi::class)
+@RunWith(AndroidTestingRunner::class)
+@SmallTest
+class TaskSwitchInteractorTest : SysuiTestCase() {
+
+    private val dispatcher = UnconfinedTestDispatcher()
+    private val testScope = TestScope(dispatcher)
+
+    private val fakeActivityTaskManager = FakeActivityTaskManager()
+    private val mediaRepo = FakeMediaProjectionRepository()
+    private val tasksRepo =
+        ActivityTaskManagerTasksRepository(
+            activityTaskManager = fakeActivityTaskManager.activityTaskManager,
+            applicationScope = testScope.backgroundScope,
+            backgroundDispatcher = dispatcher
+        )
+
+    private val interactor = TaskSwitchInteractor(mediaRepo, tasksRepo)
+
+    @Test
+    fun taskSwitchChanges_notProjecting_foregroundTaskChange_emitsNotProjectingTask() =
+        testScope.runTest {
+            mediaRepo.stopProjecting()
+            val taskSwitchState by collectLastValue(interactor.taskSwitchChanges)
+
+            fakeActivityTaskManager.moveTaskToForeground(createTask(taskId = 1))
+
+            assertThat(taskSwitchState).isEqualTo(TaskSwitchState.NotProjectingTask)
+        }
+
+    @Test
+    fun taskSwitchChanges_projectingScreen_foregroundTaskChange_emitsNotProjectingTask() =
+        testScope.runTest {
+            mediaRepo.projectEntireScreen()
+            val taskSwitchState by collectLastValue(interactor.taskSwitchChanges)
+
+            fakeActivityTaskManager.moveTaskToForeground(createTask(taskId = 1))
+
+            assertThat(taskSwitchState).isEqualTo(TaskSwitchState.NotProjectingTask)
+        }
+
+    @Test
+    fun taskSwitchChanges_projectingTask_foregroundTaskDifferent_emitsTaskChanged() =
+        testScope.runTest {
+            val projectedTask = createTask(taskId = 0)
+            val foregroundTask = createTask(taskId = 1)
+            mediaRepo.switchProjectedTask(projectedTask)
+            val taskSwitchState by collectLastValue(interactor.taskSwitchChanges)
+
+            fakeActivityTaskManager.moveTaskToForeground(foregroundTask)
+
+            assertThat(taskSwitchState)
+                .isEqualTo(
+                    TaskSwitchState.TaskSwitched(
+                        projectedTask = projectedTask,
+                        foregroundTask = foregroundTask
+                    )
+                )
+        }
+
+    @Test
+    fun taskSwitchChanges_projectingTask_foregroundTaskLauncher_emitsTaskUnchanged() =
+        testScope.runTest {
+            val projectedTask = createTask(taskId = 0)
+            val foregroundTask = createTask(taskId = 1, baseIntent = LAUNCHER_INTENT)
+            mediaRepo.switchProjectedTask(projectedTask)
+            val taskSwitchState by collectLastValue(interactor.taskSwitchChanges)
+
+            fakeActivityTaskManager.moveTaskToForeground(foregroundTask)
+
+            assertThat(taskSwitchState).isEqualTo(TaskSwitchState.TaskUnchanged)
+        }
+
+    @Test
+    fun taskSwitchChanges_projectingTask_foregroundTaskSame_emitsTaskUnchanged() =
+        testScope.runTest {
+            val projectedTask = createTask(taskId = 0)
+            val foregroundTask = createTask(taskId = 0)
+            mediaRepo.switchProjectedTask(projectedTask)
+            val taskSwitchState by collectLastValue(interactor.taskSwitchChanges)
+
+            fakeActivityTaskManager.moveTaskToForeground(foregroundTask)
+
+            assertThat(taskSwitchState).isEqualTo(TaskSwitchState.TaskUnchanged)
+        }
+
+    companion object {
+        private val LAUNCHER_INTENT: Intent =
+            Intent(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_HOME)
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/ui/viewmodel/TaskSwitcherNotificationViewModelTest.kt b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/ui/viewmodel/TaskSwitcherNotificationViewModelTest.kt
new file mode 100644
index 000000000000..ea44fb3b1f6e
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/mediaprojection/taskswitcher/ui/viewmodel/TaskSwitcherNotificationViewModelTest.kt
@@ -0,0 +1,141 @@
+/*
+ * Copyright (C) 2023 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.systemui.mediaprojection.taskswitcher.ui.viewmodel
+
+import android.content.Intent
+import android.testing.AndroidTestingRunner
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.coroutines.collectLastValue
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.ActivityTaskManagerTasksRepository
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeActivityTaskManager
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeActivityTaskManager.Companion.createTask
+import com.android.systemui.mediaprojection.taskswitcher.data.repository.FakeMediaProjectionRepository
+import com.android.systemui.mediaprojection.taskswitcher.domain.interactor.TaskSwitchInteractor
+import com.android.systemui.mediaprojection.taskswitcher.ui.model.TaskSwitcherNotificationUiState
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.test.TestScope
+import kotlinx.coroutines.test.UnconfinedTestDispatcher
+import kotlinx.coroutines.test.runTest
+import org.junit.Test
+import org.junit.runner.RunWith
+
+@OptIn(ExperimentalCoroutinesApi::class)
+@RunWith(AndroidTestingRunner::class)
+@SmallTest
+class TaskSwitcherNotificationViewModelTest : SysuiTestCase() {
+
+    private val dispatcher = UnconfinedTestDispatcher()
+    private val testScope = TestScope(dispatcher)
+
+    private val fakeActivityTaskManager = FakeActivityTaskManager()
+    private val mediaRepo = FakeMediaProjectionRepository()
+    private val tasksRepo =
+        ActivityTaskManagerTasksRepository(
+            activityTaskManager = fakeActivityTaskManager.activityTaskManager,
+            applicationScope = testScope.backgroundScope,
+            backgroundDispatcher = dispatcher
+        )
+    private val interactor = TaskSwitchInteractor(mediaRepo, tasksRepo)
+
+    private val viewModel = TaskSwitcherNotificationViewModel(interactor)
+
+    @Test
+    fun uiState_notProjecting_emitsNotShowing() =
+        testScope.runTest {
+            mediaRepo.stopProjecting()
+            val uiState by collectLastValue(viewModel.uiState)
+
+            assertThat(uiState).isEqualTo(TaskSwitcherNotificationUiState.NotShowing)
+        }
+
+    @Test
+    fun uiState_notProjecting_foregroundTaskChanged_emitsNotShowing() =
+        testScope.runTest {
+            mediaRepo.stopProjecting()
+            val uiState by collectLastValue(viewModel.uiState)
+
+            mediaRepo.switchProjectedTask(createTask(taskId = 1))
+
+            assertThat(uiState).isEqualTo(TaskSwitcherNotificationUiState.NotShowing)
+        }
+
+    @Test
+    fun uiState_projectingEntireScreen_emitsNotShowing() =
+        testScope.runTest {
+            mediaRepo.projectEntireScreen()
+            val uiState by collectLastValue(viewModel.uiState)
+
+            assertThat(uiState).isEqualTo(TaskSwitcherNotificationUiState.NotShowing)
+        }
+
+    @Test
+    fun uiState_projectingEntireScreen_foregroundTaskChanged_emitsNotShowing() =
+        testScope.runTest {
+            mediaRepo.projectEntireScreen()
+            val uiState by collectLastValue(viewModel.uiState)
+
+            mediaRepo.switchProjectedTask(createTask(taskId = 1))
+
+            assertThat(uiState).isEqualTo(TaskSwitcherNotificationUiState.NotShowing)
+        }
+
+    @Test
+    fun uiState_projectingTask_foregroundTaskChanged_different_emitsShowing() =
+        testScope.runTest {
+            val projectedTask = createTask(taskId = 1)
+            val foregroundTask = createTask(taskId = 2)
+            mediaRepo.switchProjectedTask(projectedTask)
+            val uiState by collectLastValue(viewModel.uiState)
+
+            fakeActivityTaskManager.moveTaskToForeground(foregroundTask)
+
+            assertThat(uiState)
+                .isEqualTo(TaskSwitcherNotificationUiState.Showing(projectedTask, foregroundTask))
+        }
+
+    @Test
+    fun uiState_projectingTask_foregroundTaskChanged_same_emitsNotShowing() =
+        testScope.runTest {
+            val projectedTask = createTask(taskId = 1)
+            mediaRepo.switchProjectedTask(projectedTask)
+            val uiState by collectLastValue(viewModel.uiState)
+
+            fakeActivityTaskManager.moveTaskToForeground(projectedTask)
+
+            assertThat(uiState).isEqualTo(TaskSwitcherNotificationUiState.NotShowing)
+        }
+
+    @Test
+    fun uiState_projectingTask_foregroundTaskChanged_different_taskIsLauncher_emitsNotShowing() =
+        testScope.runTest {
+            val projectedTask = createTask(taskId = 1)
+            val foregroundTask = createTask(taskId = 2, baseIntent = LAUNCHER_INTENT)
+            mediaRepo.switchProjectedTask(projectedTask)
+            val uiState by collectLastValue(viewModel.uiState)
+
+            fakeActivityTaskManager.moveTaskToForeground(foregroundTask)
+
+            assertThat(uiState).isEqualTo(TaskSwitcherNotificationUiState.NotShowing)
+        }
+
+    companion object {
+        private val LAUNCHER_INTENT: Intent =
+            Intent(Intent.ACTION_MAIN).addCategory(Intent.CATEGORY_HOME)
+    }
+}