Multi-user customizable quick affordances.

This CL adds support for multi-users to the customizable lock screen
quick affordance system.

The process that creates windows and renders System UI is always the
primary user's system UI process. The process that owns the content
provider accessed by Wallpaper Picker is bound to the currently-selected
user on the system, which may be different than the primary user.

What this means is that, when switching to a secondary user, what the
Wallpaper Picker sees is fed to it from a secondary system UI process
which is not the same system UI process that is rendering the
affordances on the lock screen. Therefore, it didn't work.

This CL adds a "remote user" selection manager which the repository can
switch to when it's running on the primary user process but needs to
query the state of the selected affordances for a secondary user.

The "remote user" selection manager queries the content provider
associated with the system UI process linked to the secondary user. This
way, we can display the correct affordances on the screen, even when
switching to a secondary user.

Fix: 260251307
Test: included new and expanded unit tests. Manually verified that the
selection of quick affordances for the primary and secondary user are
correctly reflected on the lock screen when switching users and is
retained even after switching away and back.

Change-Id: I281577ed6efb987c23b19c2078e77c91e45ce9f2
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardDataQuickAffordanceModule.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardDataQuickAffordanceModule.kt
index 3013227c..072cfb1 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardDataQuickAffordanceModule.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardDataQuickAffordanceModule.kt
@@ -17,27 +17,35 @@
 
 package com.android.systemui.keyguard.data.quickaffordance
 
+import dagger.Binds
 import dagger.Module
 import dagger.Provides
 import dagger.multibindings.ElementsIntoSet
 
 @Module
-object KeyguardDataQuickAffordanceModule {
-    @Provides
-    @ElementsIntoSet
-    fun quickAffordanceConfigs(
-        flashlight: FlashlightQuickAffordanceConfig,
-        home: HomeControlsKeyguardQuickAffordanceConfig,
-        quickAccessWallet: QuickAccessWalletKeyguardQuickAffordanceConfig,
-        qrCodeScanner: QrCodeScannerKeyguardQuickAffordanceConfig,
-        camera: CameraQuickAffordanceConfig,
-    ): Set<KeyguardQuickAffordanceConfig> {
-        return setOf(
-            camera,
-            flashlight,
-            home,
-            quickAccessWallet,
-            qrCodeScanner,
-        )
+interface KeyguardDataQuickAffordanceModule {
+    @Binds
+    fun providerClientFactory(
+        impl: KeyguardQuickAffordanceProviderClientFactoryImpl,
+    ): KeyguardQuickAffordanceProviderClientFactory
+
+    companion object {
+        @Provides
+        @ElementsIntoSet
+        fun quickAffordanceConfigs(
+            flashlight: FlashlightQuickAffordanceConfig,
+            home: HomeControlsKeyguardQuickAffordanceConfig,
+            quickAccessWallet: QuickAccessWalletKeyguardQuickAffordanceConfig,
+            qrCodeScanner: QrCodeScannerKeyguardQuickAffordanceConfig,
+            camera: CameraQuickAffordanceConfig,
+        ): Set<KeyguardQuickAffordanceConfig> {
+            return setOf(
+                camera,
+                flashlight,
+                home,
+                quickAccessWallet,
+                qrCodeScanner,
+            )
+        }
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncer.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncer.kt
index 766096f..72747f6 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncer.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncer.kt
@@ -67,7 +67,7 @@
     @Application private val scope: CoroutineScope,
     @Background private val backgroundDispatcher: CoroutineDispatcher,
     private val secureSettings: SecureSettings,
-    private val selectionsManager: KeyguardQuickAffordanceSelectionManager,
+    private val selectionsManager: KeyguardQuickAffordanceLocalUserSelectionManager,
 ) {
     companion object {
         private val BINDINGS =
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLocalUserSelectionManager.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLocalUserSelectionManager.kt
new file mode 100644
index 0000000..0066785
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLocalUserSelectionManager.kt
@@ -0,0 +1,184 @@
+/*
+ * Copyright (C) 2022 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.keyguard.data.quickaffordance
+
+import android.content.Context
+import android.content.IntentFilter
+import android.content.SharedPreferences
+import com.android.systemui.R
+import com.android.systemui.backup.BackupHelper
+import com.android.systemui.broadcast.BroadcastDispatcher
+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.settings.UserFileManager
+import com.android.systemui.settings.UserTracker
+import javax.inject.Inject
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.combine
+import kotlinx.coroutines.flow.flatMapLatest
+import kotlinx.coroutines.flow.onStart
+
+/**
+ * Manages and provides access to the current "selections" of keyguard quick affordances, answering
+ * the question "which affordances should the keyguard show?" for the user associated with the
+ * System UI process.
+ */
+@OptIn(ExperimentalCoroutinesApi::class)
+@SysUISingleton
+class KeyguardQuickAffordanceLocalUserSelectionManager
+@Inject
+constructor(
+    @Application context: Context,
+    private val userFileManager: UserFileManager,
+    private val userTracker: UserTracker,
+    broadcastDispatcher: BroadcastDispatcher,
+) : KeyguardQuickAffordanceSelectionManager {
+
+    private var sharedPrefs: SharedPreferences = instantiateSharedPrefs()
+
+    private val userId: Flow<Int> = conflatedCallbackFlow {
+        val callback =
+            object : UserTracker.Callback {
+                override fun onUserChanged(newUser: Int, userContext: Context) {
+                    trySendWithFailureLogging(newUser, TAG)
+                }
+            }
+
+        userTracker.addCallback(callback) { it.run() }
+        trySendWithFailureLogging(userTracker.userId, TAG)
+
+        awaitClose { userTracker.removeCallback(callback) }
+    }
+
+    private val defaults: Map<String, List<String>> by lazy {
+        context.resources
+            .getStringArray(R.array.config_keyguardQuickAffordanceDefaults)
+            .associate { item ->
+                val splitUp = item.split(SLOT_AFFORDANCES_DELIMITER)
+                check(splitUp.size == 2)
+                val slotId = splitUp[0]
+                val affordanceIds = splitUp[1].split(AFFORDANCE_DELIMITER)
+                slotId to affordanceIds
+            }
+    }
+
+    /**
+     * Emits an event each time a Backup & Restore restoration job is completed. Does not emit an
+     * initial value.
+     */
+    private val backupRestorationEvents: Flow<Unit> =
+        broadcastDispatcher.broadcastFlow(
+            filter = IntentFilter(BackupHelper.ACTION_RESTORE_FINISHED),
+            flags = Context.RECEIVER_NOT_EXPORTED,
+            permission = BackupHelper.PERMISSION_SELF,
+        )
+
+    override val selections: Flow<Map<String, List<String>>> =
+        combine(
+                userId,
+                backupRestorationEvents.onStart {
+                    // We emit an initial event to make sure that the combine emits at least once,
+                    // even if we never get a Backup & Restore restoration event (which is the most
+                    // common case anyway as restoration really only happens on initial device
+                    // setup).
+                    emit(Unit)
+                }
+            ) { _, _ -> }
+            .flatMapLatest {
+                conflatedCallbackFlow {
+                    // We want to instantiate a new SharedPreferences instance each time either the
+                    // user ID changes or we have a backup & restore restoration event. The reason
+                    // is that our sharedPrefs instance needs to be replaced with a new one as it
+                    // depends on the user ID and when the B&R job completes, the backing file is
+                    // replaced but the existing instance still has a stale in-memory cache.
+                    sharedPrefs = instantiateSharedPrefs()
+
+                    val listener =
+                        SharedPreferences.OnSharedPreferenceChangeListener { _, _ ->
+                            trySend(getSelections())
+                        }
+
+                    sharedPrefs.registerOnSharedPreferenceChangeListener(listener)
+                    send(getSelections())
+
+                    awaitClose { sharedPrefs.unregisterOnSharedPreferenceChangeListener(listener) }
+                }
+            }
+
+    override fun getSelections(): Map<String, List<String>> {
+        val slotKeys = sharedPrefs.all.keys.filter { it.startsWith(KEY_PREFIX_SLOT) }
+        val result =
+            slotKeys
+                .associate { key ->
+                    val slotId = key.substring(KEY_PREFIX_SLOT.length)
+                    val value = sharedPrefs.getString(key, null)
+                    val affordanceIds =
+                        if (!value.isNullOrEmpty()) {
+                            value.split(AFFORDANCE_DELIMITER)
+                        } else {
+                            emptyList()
+                        }
+                    slotId to affordanceIds
+                }
+                .toMutableMap()
+
+        // If the result map is missing keys, it means that the system has never set anything for
+        // those slots. This is where we need examine our defaults and see if there should be a
+        // default value for the affordances in the slot IDs that are missing from the result.
+        //
+        // Once the user makes any selection for a slot, even when they select "None", this class
+        // will persist a key for that slot ID. In the case of "None", it will have a value of the
+        // empty string. This is why this system works.
+        defaults.forEach { (slotId, affordanceIds) ->
+            if (!result.containsKey(slotId)) {
+                result[slotId] = affordanceIds
+            }
+        }
+
+        return result
+    }
+
+    override fun setSelections(
+        slotId: String,
+        affordanceIds: List<String>,
+    ) {
+        val key = "$KEY_PREFIX_SLOT$slotId"
+        val value = affordanceIds.joinToString(AFFORDANCE_DELIMITER)
+        sharedPrefs.edit().putString(key, value).apply()
+    }
+
+    private fun instantiateSharedPrefs(): SharedPreferences {
+        return userFileManager.getSharedPreferences(
+            FILE_NAME,
+            Context.MODE_PRIVATE,
+            userTracker.userId,
+        )
+    }
+
+    companion object {
+        private const val TAG = "KeyguardQuickAffordancePrimaryUserSelectionManager"
+        const val FILE_NAME = "quick_affordance_selections"
+        private const val KEY_PREFIX_SLOT = "slot_"
+        private const val SLOT_AFFORDANCES_DELIMITER = ":"
+        private const val AFFORDANCE_DELIMITER = ","
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceProviderClientFactory.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceProviderClientFactory.kt
new file mode 100644
index 0000000..727a813
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceProviderClientFactory.kt
@@ -0,0 +1,43 @@
+/*
+ * Copyright (C) 2022 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.keyguard.data.quickaffordance
+
+import com.android.systemui.dagger.qualifiers.Background
+import com.android.systemui.settings.UserTracker
+import com.android.systemui.shared.quickaffordance.data.content.KeyguardQuickAffordanceProviderClient
+import com.android.systemui.shared.quickaffordance.data.content.KeyguardQuickAffordanceProviderClientImpl
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineDispatcher
+
+interface KeyguardQuickAffordanceProviderClientFactory {
+    fun create(): KeyguardQuickAffordanceProviderClient
+}
+
+class KeyguardQuickAffordanceProviderClientFactoryImpl
+@Inject
+constructor(
+    private val userTracker: UserTracker,
+    @Background private val backgroundDispatcher: CoroutineDispatcher,
+) : KeyguardQuickAffordanceProviderClientFactory {
+    override fun create(): KeyguardQuickAffordanceProviderClient {
+        return KeyguardQuickAffordanceProviderClientImpl(
+            context = userTracker.userContext,
+            backgroundDispatcher = backgroundDispatcher,
+        )
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceRemoteUserSelectionManager.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceRemoteUserSelectionManager.kt
new file mode 100644
index 0000000..8ffef25
--- /dev/null
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceRemoteUserSelectionManager.kt
@@ -0,0 +1,129 @@
+/*
+ * Copyright (C) 2022 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.keyguard.data.quickaffordance
+
+import android.content.Context
+import android.os.UserHandle
+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.settings.UserTracker
+import com.android.systemui.shared.quickaffordance.data.content.KeyguardQuickAffordanceProviderClient
+import javax.inject.Inject
+import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
+import kotlinx.coroutines.flow.SharingStarted
+import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.emptyFlow
+import kotlinx.coroutines.flow.flatMapLatest
+import kotlinx.coroutines.flow.map
+import kotlinx.coroutines.flow.stateIn
+import kotlinx.coroutines.launch
+
+/**
+ * Manages and provides access to the current "selections" of keyguard quick affordances, answering
+ * the question "which affordances should the keyguard show?" for users associated with other System
+ * UI processes.
+ */
+@OptIn(ExperimentalCoroutinesApi::class)
+@SysUISingleton
+class KeyguardQuickAffordanceRemoteUserSelectionManager
+@Inject
+constructor(
+    @Application private val scope: CoroutineScope,
+    private val userTracker: UserTracker,
+    private val clientFactory: KeyguardQuickAffordanceProviderClientFactory,
+    private val userHandle: UserHandle,
+) : KeyguardQuickAffordanceSelectionManager {
+
+    private val userId: Flow<Int> = conflatedCallbackFlow {
+        val callback =
+            object : UserTracker.Callback {
+                override fun onUserChanged(newUser: Int, userContext: Context) {
+                    trySendWithFailureLogging(newUser, TAG)
+                }
+            }
+
+        userTracker.addCallback(callback) { it.run() }
+        trySendWithFailureLogging(userTracker.userId, TAG)
+
+        awaitClose { userTracker.removeCallback(callback) }
+    }
+
+    private val clientOrNull: StateFlow<KeyguardQuickAffordanceProviderClient?> =
+        userId
+            .distinctUntilChanged()
+            .map { selectedUserId ->
+                if (userHandle.isSystem && userHandle.identifier != selectedUserId) {
+                    clientFactory.create()
+                } else {
+                    null
+                }
+            }
+            .stateIn(
+                scope = scope,
+                started = SharingStarted.Eagerly,
+                initialValue = null,
+            )
+
+    private val _selections: StateFlow<Map<String, List<String>>> =
+        clientOrNull
+            .flatMapLatest { client ->
+                client?.observeSelections()?.map { selections ->
+                    buildMap<String, List<String>> {
+                        selections.forEach { selection ->
+                            val slotId = selection.slotId
+                            val affordanceIds = (get(slotId) ?: emptyList()).toMutableList()
+                            affordanceIds.add(selection.affordanceId)
+                            put(slotId, affordanceIds)
+                        }
+                    }
+                }
+                    ?: emptyFlow()
+            }
+            .stateIn(
+                scope = scope,
+                started = SharingStarted.Eagerly,
+                initialValue = emptyMap(),
+            )
+
+    override val selections: Flow<Map<String, List<String>>> = _selections
+
+    override fun getSelections(): Map<String, List<String>> {
+        return _selections.value
+    }
+
+    override fun setSelections(slotId: String, affordanceIds: List<String>) {
+        clientOrNull.value?.let { client ->
+            scope.launch {
+                client.deleteAllSelections(slotId = slotId)
+                affordanceIds.forEach { affordanceId ->
+                    client.insertSelection(slotId = slotId, affordanceId = affordanceId)
+                }
+            }
+        }
+    }
+
+    companion object {
+        private const val TAG = "KeyguardQuickAffordanceMultiUserSelectionManager"
+    }
+}
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceSelectionManager.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceSelectionManager.kt
index 4f37e5f..21fffed 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceSelectionManager.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceSelectionManager.kt
@@ -17,153 +17,22 @@
 
 package com.android.systemui.keyguard.data.quickaffordance
 
-import android.content.Context
-import android.content.IntentFilter
-import android.content.SharedPreferences
-import com.android.systemui.R
-import com.android.systemui.backup.BackupHelper
-import com.android.systemui.broadcast.BroadcastDispatcher
-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.settings.UserFileManager
-import com.android.systemui.settings.UserTracker
-import javax.inject.Inject
-import kotlinx.coroutines.ExperimentalCoroutinesApi
-import kotlinx.coroutines.channels.awaitClose
 import kotlinx.coroutines.flow.Flow
-import kotlinx.coroutines.flow.combine
-import kotlinx.coroutines.flow.flatMapLatest
-import kotlinx.coroutines.flow.onStart
 
 /**
- * Manages and provides access to the current "selections" of keyguard quick affordances, answering
- * the question "which affordances should the keyguard show?".
+ * Defines interface for classes that manage and provide access to the current "selections" of
+ * keyguard quick affordances, answering the question "which affordances should the keyguard show?".
  */
-@OptIn(ExperimentalCoroutinesApi::class)
-@SysUISingleton
-class KeyguardQuickAffordanceSelectionManager
-@Inject
-constructor(
-    @Application context: Context,
-    private val userFileManager: UserFileManager,
-    private val userTracker: UserTracker,
-    broadcastDispatcher: BroadcastDispatcher,
-) {
-
-    private var sharedPrefs: SharedPreferences = instantiateSharedPrefs()
-
-    private val userId: Flow<Int> = conflatedCallbackFlow {
-        val callback =
-            object : UserTracker.Callback {
-                override fun onUserChanged(newUser: Int, userContext: Context) {
-                    trySendWithFailureLogging(newUser, TAG)
-                }
-            }
-
-        userTracker.addCallback(callback) { it.run() }
-        trySendWithFailureLogging(userTracker.userId, TAG)
-
-        awaitClose { userTracker.removeCallback(callback) }
-    }
-    private val defaults: Map<String, List<String>> by lazy {
-        context.resources
-            .getStringArray(R.array.config_keyguardQuickAffordanceDefaults)
-            .associate { item ->
-                val splitUp = item.split(SLOT_AFFORDANCES_DELIMITER)
-                check(splitUp.size == 2)
-                val slotId = splitUp[0]
-                val affordanceIds = splitUp[1].split(AFFORDANCE_DELIMITER)
-                slotId to affordanceIds
-            }
-    }
-
-    /**
-     * Emits an event each time a Backup & Restore restoration job is completed. Does not emit an
-     * initial value.
-     */
-    private val backupRestorationEvents: Flow<Unit> =
-        broadcastDispatcher.broadcastFlow(
-            filter = IntentFilter(BackupHelper.ACTION_RESTORE_FINISHED),
-            flags = Context.RECEIVER_NOT_EXPORTED,
-            permission = BackupHelper.PERMISSION_SELF,
-        )
+interface KeyguardQuickAffordanceSelectionManager {
 
     /** IDs of affordances to show, indexed by slot ID, and sorted in descending priority order. */
-    val selections: Flow<Map<String, List<String>>> =
-        combine(
-                userId,
-                backupRestorationEvents.onStart {
-                    // We emit an initial event to make sure that the combine emits at least once,
-                    // even
-                    // if we never get a Backup & Restore restoration event (which is the most
-                    // common
-                    // case anyway as restoration really only happens on initial device setup).
-                    emit(Unit)
-                }
-            ) { _, _ ->
-            }
-            .flatMapLatest {
-                conflatedCallbackFlow {
-                    // We want to instantiate a new SharedPreferences instance each time either the
-                    // user
-                    // ID changes or we have a backup & restore restoration event. The reason is
-                    // that
-                    // our sharedPrefs instance needs to be replaced with a new one as it depends on
-                    // the
-                    // user ID and when the B&R job completes, the backing file is replaced but the
-                    // existing instance still has a stale in-memory cache.
-                    sharedPrefs = instantiateSharedPrefs()
-
-                    val listener =
-                        SharedPreferences.OnSharedPreferenceChangeListener { _, _ ->
-                            trySend(getSelections())
-                        }
-
-                    sharedPrefs.registerOnSharedPreferenceChangeListener(listener)
-                    send(getSelections())
-
-                    awaitClose { sharedPrefs.unregisterOnSharedPreferenceChangeListener(listener) }
-                }
-            }
+    val selections: Flow<Map<String, List<String>>>
 
     /**
      * Returns a snapshot of the IDs of affordances to show, indexed by slot ID, and sorted in
      * descending priority order.
      */
-    fun getSelections(): Map<String, List<String>> {
-        val slotKeys = sharedPrefs.all.keys.filter { it.startsWith(KEY_PREFIX_SLOT) }
-        val result =
-            slotKeys
-                .associate { key ->
-                    val slotId = key.substring(KEY_PREFIX_SLOT.length)
-                    val value = sharedPrefs.getString(key, null)
-                    val affordanceIds =
-                        if (!value.isNullOrEmpty()) {
-                            value.split(AFFORDANCE_DELIMITER)
-                        } else {
-                            emptyList()
-                        }
-                    slotId to affordanceIds
-                }
-                .toMutableMap()
-
-        // If the result map is missing keys, it means that the system has never set anything for
-        // those slots. This is where we need examine our defaults and see if there should be a
-        // default value for the affordances in the slot IDs that are missing from the result.
-        //
-        // Once the user makes any selection for a slot, even when they select "None", this class
-        // will persist a key for that slot ID. In the case of "None", it will have a value of the
-        // empty string. This is why this system works.
-        defaults.forEach { (slotId, affordanceIds) ->
-            if (!result.containsKey(slotId)) {
-                result[slotId] = affordanceIds
-            }
-        }
-
-        return result
-    }
+    fun getSelections(): Map<String, List<String>>
 
     /**
      * Updates the IDs of affordances to show at the slot with the given ID. The order of affordance
@@ -172,25 +41,9 @@
     fun setSelections(
         slotId: String,
         affordanceIds: List<String>,
-    ) {
-        val key = "$KEY_PREFIX_SLOT$slotId"
-        val value = affordanceIds.joinToString(AFFORDANCE_DELIMITER)
-        sharedPrefs.edit().putString(key, value).apply()
-    }
-
-    private fun instantiateSharedPrefs(): SharedPreferences {
-        return userFileManager.getSharedPreferences(
-            FILE_NAME,
-            Context.MODE_PRIVATE,
-            userTracker.userId,
-        )
-    }
+    )
 
     companion object {
-        private const val TAG = "KeyguardQuickAffordanceSelectionManager"
         const val FILE_NAME = "quick_affordance_selections"
-        private const val KEY_PREFIX_SLOT = "slot_"
-        private const val SLOT_AFFORDANCES_DELIMITER = ":"
-        private const val AFFORDANCE_DELIMITER = ","
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepository.kt b/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepository.kt
index d95a1a7..e3f5e90 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepository.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepository.kt
@@ -18,45 +18,93 @@
 package com.android.systemui.keyguard.data.repository
 
 import android.content.Context
+import android.os.UserHandle
 import com.android.systemui.Dumpable
 import com.android.systemui.R
+import com.android.systemui.common.coroutine.ChannelExt.trySendWithFailureLogging
+import com.android.systemui.common.coroutine.ConflatedCallbackFlow
 import com.android.systemui.dagger.SysUISingleton
 import com.android.systemui.dagger.qualifiers.Application
 import com.android.systemui.dump.DumpManager
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceConfig
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLegacySettingSyncer
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLocalUserSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceRemoteUserSelectionManager
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceSelectionManager
 import com.android.systemui.keyguard.shared.model.KeyguardQuickAffordancePickerRepresentation
 import com.android.systemui.keyguard.shared.model.KeyguardSlotPickerRepresentation
+import com.android.systemui.settings.UserTracker
 import java.io.PrintWriter
 import javax.inject.Inject
 import kotlinx.coroutines.CoroutineScope
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.channels.awaitClose
+import kotlinx.coroutines.flow.Flow
 import kotlinx.coroutines.flow.SharingStarted
 import kotlinx.coroutines.flow.StateFlow
+import kotlinx.coroutines.flow.distinctUntilChanged
+import kotlinx.coroutines.flow.flatMapLatest
 import kotlinx.coroutines.flow.map
 import kotlinx.coroutines.flow.stateIn
 
 /** Abstracts access to application state related to keyguard quick affordances. */
+@OptIn(ExperimentalCoroutinesApi::class)
 @SysUISingleton
 class KeyguardQuickAffordanceRepository
 @Inject
 constructor(
     @Application private val appContext: Context,
     @Application private val scope: CoroutineScope,
-    private val selectionManager: KeyguardQuickAffordanceSelectionManager,
+    private val localUserSelectionManager: KeyguardQuickAffordanceLocalUserSelectionManager,
+    private val remoteUserSelectionManager: KeyguardQuickAffordanceRemoteUserSelectionManager,
+    private val userTracker: UserTracker,
     legacySettingSyncer: KeyguardQuickAffordanceLegacySettingSyncer,
     private val configs: Set<@JvmSuppressWildcards KeyguardQuickAffordanceConfig>,
     dumpManager: DumpManager,
+    userHandle: UserHandle,
 ) {
+    private val userId: Flow<Int> =
+        ConflatedCallbackFlow.conflatedCallbackFlow {
+            val callback =
+                object : UserTracker.Callback {
+                    override fun onUserChanged(newUser: Int, userContext: Context) {
+                        trySendWithFailureLogging(newUser, TAG)
+                    }
+                }
+
+            userTracker.addCallback(callback) { it.run() }
+            trySendWithFailureLogging(userTracker.userId, TAG)
+
+            awaitClose { userTracker.removeCallback(callback) }
+        }
+
+    private val selectionManager: StateFlow<KeyguardQuickAffordanceSelectionManager> =
+        userId
+            .distinctUntilChanged()
+            .map { selectedUserId ->
+                if (userHandle.identifier == selectedUserId) {
+                    localUserSelectionManager
+                } else {
+                    remoteUserSelectionManager
+                }
+            }
+            .stateIn(
+                scope = scope,
+                started = SharingStarted.Eagerly,
+                initialValue = localUserSelectionManager,
+            )
+
     /**
      * List of [KeyguardQuickAffordanceConfig] instances of the affordances at the slot with the
      * given ID. The configs are sorted in descending priority order.
      */
     val selections: StateFlow<Map<String, List<KeyguardQuickAffordanceConfig>>> =
-        selectionManager.selections
-            .map { selectionsBySlotId ->
-                selectionsBySlotId.mapValues { (_, selections) ->
-                    configs.filter { selections.contains(it.key) }
+        selectionManager
+            .flatMapLatest { selectionManager ->
+                selectionManager.selections.map { selectionsBySlotId ->
+                    selectionsBySlotId.mapValues { (_, selections) ->
+                        configs.filter { selections.contains(it.key) }
+                    }
                 }
             }
             .stateIn(
@@ -99,7 +147,7 @@
      * slot with the given ID. The configs are sorted in descending priority order.
      */
     fun getSelections(slotId: String): List<KeyguardQuickAffordanceConfig> {
-        val selections = selectionManager.getSelections().getOrDefault(slotId, emptyList())
+        val selections = selectionManager.value.getSelections().getOrDefault(slotId, emptyList())
         return configs.filter { selections.contains(it.key) }
     }
 
@@ -108,7 +156,7 @@
      * are sorted in descending priority order.
      */
     fun getSelections(): Map<String, List<String>> {
-        return selectionManager.getSelections()
+        return selectionManager.value.getSelections()
     }
 
     /**
@@ -119,7 +167,7 @@
         slotId: String,
         affordanceIds: List<String>,
     ) {
-        selectionManager.setSelections(
+        selectionManager.value.setSelections(
             slotId = slotId,
             affordanceIds = affordanceIds,
         )
@@ -188,6 +236,7 @@
     }
 
     companion object {
+        private const val TAG = "KeyguardQuickAffordanceRepository"
         private const val SLOT_CONFIG_DELIMITER = ":"
     }
 }
diff --git a/packages/SystemUI/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractor.kt b/packages/SystemUI/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractor.kt
index ee7154f..748c6e8 100644
--- a/packages/SystemUI/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractor.kt
+++ b/packages/SystemUI/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractor.kt
@@ -190,8 +190,6 @@
 
     /** Returns affordance IDs indexed by slot ID, for all known slots. */
     suspend fun getSelections(): Map<String, List<KeyguardQuickAffordancePickerRepresentation>> {
-        check(isUsingRepository)
-
         val slots = repository.get().getSlotPickerRepresentations()
         val selections = repository.get().getSelections()
         val affordanceById =
@@ -312,8 +310,6 @@
 
     suspend fun getAffordancePickerRepresentations():
         List<KeyguardQuickAffordancePickerRepresentation> {
-        check(isUsingRepository)
-
         return repository.get().getAffordancePickerRepresentations()
     }
 
diff --git a/packages/SystemUI/src/com/android/systemui/user/UserModule.java b/packages/SystemUI/src/com/android/systemui/user/UserModule.java
index 0c72b78..2b29885 100644
--- a/packages/SystemUI/src/com/android/systemui/user/UserModule.java
+++ b/packages/SystemUI/src/com/android/systemui/user/UserModule.java
@@ -17,6 +17,7 @@
 package com.android.systemui.user;
 
 import android.app.Activity;
+import android.os.UserHandle;
 
 import com.android.settingslib.users.EditUserInfoController;
 import com.android.systemui.user.data.repository.UserRepositoryModule;
@@ -51,4 +52,22 @@
     @IntoMap
     @ClassKey(UserSwitcherActivity.class)
     public abstract Activity provideUserSwitcherActivity(UserSwitcherActivity activity);
+
+    /**
+     * Provides the {@link UserHandle} for the user associated with this System UI process.
+     *
+     * <p>Note that this is static and unchanging for the life-time of the process we are running
+     * in. It can be <i>different</i> from the user that is the currently-selected user, which may
+     * be associated with a different System UI process.
+     *
+     * <p>For example, the System UI process which creates all the windows and renders UI is always
+     * the one associated with the primary user on the device. However, if the user is switched to
+     * another, non-primary user (for example user "X"), then a secondary System UI process will be
+     * spawned. While the original primary user process continues to be the only one rendering UI,
+     * the new system UI process may be used for things like file or content access.
+     */
+    @Provides
+    public static UserHandle provideUserHandle() {
+        return new UserHandle(UserHandle.myUserId());
+    }
 }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/KeyguardQuickAffordanceProviderTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/KeyguardQuickAffordanceProviderTest.kt
index 32c5b3f..cef452b 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/KeyguardQuickAffordanceProviderTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/KeyguardQuickAffordanceProviderTest.kt
@@ -20,6 +20,7 @@
 import android.content.ContentValues
 import android.content.pm.PackageManager
 import android.content.pm.ProviderInfo
+import android.os.UserHandle
 import androidx.test.filters.SmallTest
 import com.android.internal.widget.LockPatternUtils
 import com.android.systemui.SystemUIAppComponentFactoryBase
@@ -27,8 +28,10 @@
 import com.android.systemui.flags.FakeFeatureFlags
 import com.android.systemui.flags.Flags
 import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceConfig
+import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceProviderClientFactory
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLegacySettingSyncer
-import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLocalUserSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceRemoteUserSelectionManager
 import com.android.systemui.keyguard.data.repository.FakeKeyguardRepository
 import com.android.systemui.keyguard.data.repository.KeyguardQuickAffordanceRepository
 import com.android.systemui.keyguard.domain.interactor.KeyguardInteractor
@@ -74,8 +77,8 @@
 
         underTest = KeyguardQuickAffordanceProvider()
         val scope = CoroutineScope(IMMEDIATE)
-        val selectionManager =
-            KeyguardQuickAffordanceSelectionManager(
+        val localUserSelectionManager =
+            KeyguardQuickAffordanceLocalUserSelectionManager(
                 context = context,
                 userFileManager =
                     mock<UserFileManager>().apply {
@@ -91,11 +94,20 @@
                 userTracker = userTracker,
                 broadcastDispatcher = fakeBroadcastDispatcher,
             )
+        val remoteUserSelectionManager =
+            KeyguardQuickAffordanceRemoteUserSelectionManager(
+                scope = scope,
+                userTracker = userTracker,
+                clientFactory = FakeKeyguardQuickAffordanceProviderClientFactory(userTracker),
+                userHandle = UserHandle.SYSTEM,
+            )
         val quickAffordanceRepository =
             KeyguardQuickAffordanceRepository(
                 appContext = context,
                 scope = scope,
-                selectionManager = selectionManager,
+                localUserSelectionManager = localUserSelectionManager,
+                remoteUserSelectionManager = remoteUserSelectionManager,
+                userTracker = userTracker,
                 configs =
                     setOf(
                         FakeKeyguardQuickAffordanceConfig(
@@ -114,9 +126,10 @@
                         scope = scope,
                         backgroundDispatcher = IMMEDIATE,
                         secureSettings = FakeSettings(),
-                        selectionsManager = selectionManager,
+                        selectionsManager = localUserSelectionManager,
                     ),
                 dumpManager = mock(),
+                userHandle = UserHandle.SYSTEM,
             )
         underTest.interactor =
             KeyguardQuickAffordanceInteractor(
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncerTest.kt
index 552b8cb..3b0169d 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncerTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLegacySettingSyncerTest.kt
@@ -57,7 +57,7 @@
 
     private lateinit var testScope: TestScope
     private lateinit var testDispatcher: TestDispatcher
-    private lateinit var selectionManager: KeyguardQuickAffordanceSelectionManager
+    private lateinit var selectionManager: KeyguardQuickAffordanceLocalUserSelectionManager
     private lateinit var settings: FakeSettings
 
     @Before
@@ -75,7 +75,7 @@
         testDispatcher = UnconfinedTestDispatcher()
         testScope = TestScope(testDispatcher)
         selectionManager =
-            KeyguardQuickAffordanceSelectionManager(
+            KeyguardQuickAffordanceLocalUserSelectionManager(
                 context = context,
                 userFileManager =
                     mock {
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceSelectionManagerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLocalUserSelectionManagerTest.kt
similarity index 97%
rename from packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceSelectionManagerTest.kt
rename to packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLocalUserSelectionManagerTest.kt
index 6a2376b..67091a9 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceSelectionManagerTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceLocalUserSelectionManagerTest.kt
@@ -52,11 +52,11 @@
 @OptIn(ExperimentalCoroutinesApi::class)
 @SmallTest
 @RunWith(JUnit4::class)
-class KeyguardQuickAffordanceSelectionManagerTest : SysuiTestCase() {
+class KeyguardQuickAffordanceLocalUserSelectionManagerTest : SysuiTestCase() {
 
     @Mock private lateinit var userFileManager: UserFileManager
 
-    private lateinit var underTest: KeyguardQuickAffordanceSelectionManager
+    private lateinit var underTest: KeyguardQuickAffordanceLocalUserSelectionManager
 
     private lateinit var userTracker: FakeUserTracker
     private lateinit var sharedPrefs: MutableMap<Int, SharedPreferences>
@@ -74,7 +74,7 @@
         Dispatchers.setMain(dispatcher)
 
         underTest =
-            KeyguardQuickAffordanceSelectionManager(
+            KeyguardQuickAffordanceLocalUserSelectionManager(
                 context = context,
                 userFileManager = userFileManager,
                 userTracker = userTracker,
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceRemoteUserSelectionManagerTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceRemoteUserSelectionManagerTest.kt
new file mode 100644
index 0000000..d7e9cf1
--- /dev/null
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/quickaffordance/KeyguardQuickAffordanceRemoteUserSelectionManagerTest.kt
@@ -0,0 +1,219 @@
+/*
+ * Copyright (C) 2022 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.keyguard.data.quickaffordance
+
+import android.content.pm.UserInfo
+import android.os.UserHandle
+import androidx.test.filters.SmallTest
+import com.android.systemui.SysuiTestCase
+import com.android.systemui.settings.FakeUserTracker
+import com.android.systemui.shared.keyguard.shared.model.KeyguardQuickAffordanceSlots
+import com.android.systemui.shared.quickaffordance.data.content.FakeKeyguardQuickAffordanceProviderClient
+import com.android.systemui.util.mockito.whenever
+import com.google.common.truth.Truth.assertThat
+import kotlinx.coroutines.ExperimentalCoroutinesApi
+import kotlinx.coroutines.flow.toList
+import kotlinx.coroutines.launch
+import kotlinx.coroutines.test.StandardTestDispatcher
+import kotlinx.coroutines.test.TestDispatcher
+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
+import org.junit.runners.JUnit4
+import org.mockito.Mock
+import org.mockito.MockitoAnnotations
+
+@OptIn(ExperimentalCoroutinesApi::class)
+@SmallTest
+@RunWith(JUnit4::class)
+class KeyguardQuickAffordanceRemoteUserSelectionManagerTest : SysuiTestCase() {
+
+    @Mock private lateinit var userHandle: UserHandle
+
+    private lateinit var underTest: KeyguardQuickAffordanceRemoteUserSelectionManager
+
+    private lateinit var clientFactory: FakeKeyguardQuickAffordanceProviderClientFactory
+    private lateinit var testScope: TestScope
+    private lateinit var testDispatcher: TestDispatcher
+    private lateinit var userTracker: FakeUserTracker
+    private lateinit var client1: FakeKeyguardQuickAffordanceProviderClient
+    private lateinit var client2: FakeKeyguardQuickAffordanceProviderClient
+
+    @Before
+    fun setUp() {
+        MockitoAnnotations.initMocks(this)
+        whenever(userHandle.identifier).thenReturn(UserHandle.USER_SYSTEM)
+        whenever(userHandle.isSystem).thenReturn(true)
+        client1 = FakeKeyguardQuickAffordanceProviderClient()
+        client2 = FakeKeyguardQuickAffordanceProviderClient()
+
+        userTracker = FakeUserTracker()
+        userTracker.set(
+            userInfos =
+                listOf(
+                    UserInfo(
+                        UserHandle.USER_SYSTEM,
+                        "Primary",
+                        /* flags= */ 0,
+                    ),
+                    UserInfo(
+                        OTHER_USER_ID_1,
+                        "Secondary 1",
+                        /* flags= */ 0,
+                    ),
+                    UserInfo(
+                        OTHER_USER_ID_2,
+                        "Secondary 2",
+                        /* flags= */ 0,
+                    ),
+                ),
+            selectedUserIndex = 0,
+        )
+
+        clientFactory =
+            FakeKeyguardQuickAffordanceProviderClientFactory(
+                userTracker,
+            ) { selectedUserId ->
+                when (selectedUserId) {
+                    OTHER_USER_ID_1 -> client1
+                    OTHER_USER_ID_2 -> client2
+                    else -> error("No client set-up for user $selectedUserId!")
+                }
+            }
+
+        testDispatcher = StandardTestDispatcher()
+        testScope = TestScope(testDispatcher)
+
+        underTest =
+            KeyguardQuickAffordanceRemoteUserSelectionManager(
+                scope = testScope.backgroundScope,
+                userTracker = userTracker,
+                clientFactory = clientFactory,
+                userHandle = userHandle,
+            )
+    }
+
+    @Test
+    fun `selections - primary user process`() =
+        testScope.runTest {
+            val values = mutableListOf<Map<String, List<String>>>()
+            val job = launch { underTest.selections.toList(values) }
+
+            runCurrent()
+            assertThat(values.last()).isEmpty()
+
+            client1.insertSelection(
+                slotId = KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_START,
+                affordanceId = FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_1,
+            )
+            client2.insertSelection(
+                slotId = KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_END,
+                affordanceId = FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_2,
+            )
+
+            userTracker.set(
+                userInfos = userTracker.userProfiles,
+                selectedUserIndex = 1,
+            )
+            runCurrent()
+            assertThat(values.last())
+                .isEqualTo(
+                    mapOf(
+                        KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_START to
+                            listOf(
+                                FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_1,
+                            ),
+                    )
+                )
+
+            userTracker.set(
+                userInfos = userTracker.userProfiles,
+                selectedUserIndex = 2,
+            )
+            runCurrent()
+            assertThat(values.last())
+                .isEqualTo(
+                    mapOf(
+                        KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_END to
+                            listOf(
+                                FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_2,
+                            ),
+                    )
+                )
+
+            job.cancel()
+        }
+
+    @Test
+    fun `selections - secondary user process - always empty`() =
+        testScope.runTest {
+            whenever(userHandle.isSystem).thenReturn(false)
+            val values = mutableListOf<Map<String, List<String>>>()
+            val job = launch { underTest.selections.toList(values) }
+
+            runCurrent()
+            assertThat(values.last()).isEmpty()
+
+            client1.insertSelection(
+                slotId = KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_START,
+                affordanceId = FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_1,
+            )
+            userTracker.set(
+                userInfos = userTracker.userProfiles,
+                selectedUserIndex = 1,
+            )
+            runCurrent()
+            assertThat(values.last()).isEmpty()
+
+            job.cancel()
+        }
+
+    @Test
+    fun setSelections() =
+        testScope.runTest {
+            userTracker.set(
+                userInfos = userTracker.userProfiles,
+                selectedUserIndex = 1,
+            )
+            runCurrent()
+
+            underTest.setSelections(
+                slotId = KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_START,
+                affordanceIds = listOf(FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_1),
+            )
+            runCurrent()
+
+            assertThat(underTest.getSelections())
+                .isEqualTo(
+                    mapOf(
+                        KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_START to
+                            listOf(
+                                FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_1,
+                            ),
+                    )
+                )
+        }
+
+    companion object {
+        private const val OTHER_USER_ID_1 = UserHandle.MIN_SECONDARY_USER_ID + 1
+        private const val OTHER_USER_ID_2 = UserHandle.MIN_SECONDARY_USER_ID + 2
+    }
+}
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepositoryTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepositoryTest.kt
index 652fae9..c40488a 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepositoryTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/data/repository/KeyguardQuickAffordanceRepositoryTest.kt
@@ -17,17 +17,23 @@
 
 package com.android.systemui.keyguard.data.repository
 
+import android.content.pm.UserInfo
+import android.os.UserHandle
 import androidx.test.filters.SmallTest
 import com.android.systemui.R
 import com.android.systemui.SysuiTestCase
 import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceConfig
+import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceProviderClientFactory
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceConfig
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLegacySettingSyncer
-import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLocalUserSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceRemoteUserSelectionManager
 import com.android.systemui.keyguard.shared.model.KeyguardQuickAffordancePickerRepresentation
 import com.android.systemui.keyguard.shared.model.KeyguardSlotPickerRepresentation
 import com.android.systemui.settings.FakeUserTracker
 import com.android.systemui.settings.UserFileManager
+import com.android.systemui.shared.keyguard.shared.model.KeyguardQuickAffordanceSlots
+import com.android.systemui.shared.quickaffordance.data.content.FakeKeyguardQuickAffordanceProviderClient
 import com.android.systemui.util.FakeSharedPreferences
 import com.android.systemui.util.mockito.mock
 import com.android.systemui.util.mockito.whenever
@@ -39,6 +45,7 @@
 import kotlinx.coroutines.flow.launchIn
 import kotlinx.coroutines.flow.onEach
 import kotlinx.coroutines.runBlocking
+import kotlinx.coroutines.yield
 import org.junit.Before
 import org.junit.Test
 import org.junit.runner.RunWith
@@ -55,14 +62,24 @@
 
     private lateinit var config1: FakeKeyguardQuickAffordanceConfig
     private lateinit var config2: FakeKeyguardQuickAffordanceConfig
+    private lateinit var userTracker: FakeUserTracker
+    private lateinit var client1: FakeKeyguardQuickAffordanceProviderClient
+    private lateinit var client2: FakeKeyguardQuickAffordanceProviderClient
 
     @Before
     fun setUp() {
-        config1 = FakeKeyguardQuickAffordanceConfig("built_in:1")
-        config2 = FakeKeyguardQuickAffordanceConfig("built_in:2")
+        config1 =
+            FakeKeyguardQuickAffordanceConfig(
+                FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_1
+            )
+        config2 =
+            FakeKeyguardQuickAffordanceConfig(
+                FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_2
+            )
         val scope = CoroutineScope(IMMEDIATE)
-        val selectionManager =
-            KeyguardQuickAffordanceSelectionManager(
+        userTracker = FakeUserTracker()
+        val localUserSelectionManager =
+            KeyguardQuickAffordanceLocalUserSelectionManager(
                 context = context,
                 userFileManager =
                     mock<UserFileManager>().apply {
@@ -75,24 +92,45 @@
                             )
                             .thenReturn(FakeSharedPreferences())
                     },
-                userTracker = FakeUserTracker(),
+                userTracker = userTracker,
                 broadcastDispatcher = fakeBroadcastDispatcher,
             )
+        client1 = FakeKeyguardQuickAffordanceProviderClient()
+        client2 = FakeKeyguardQuickAffordanceProviderClient()
+        val remoteUserSelectionManager =
+            KeyguardQuickAffordanceRemoteUserSelectionManager(
+                scope = scope,
+                userTracker = userTracker,
+                clientFactory =
+                    FakeKeyguardQuickAffordanceProviderClientFactory(
+                        userTracker,
+                    ) { selectedUserId ->
+                        when (selectedUserId) {
+                            SECONDARY_USER_1 -> client1
+                            SECONDARY_USER_2 -> client2
+                            else -> error("No set-up client for user $selectedUserId!")
+                        }
+                    },
+                userHandle = UserHandle.SYSTEM,
+            )
 
         underTest =
             KeyguardQuickAffordanceRepository(
                 appContext = context,
                 scope = scope,
-                selectionManager = selectionManager,
+                localUserSelectionManager = localUserSelectionManager,
+                remoteUserSelectionManager = remoteUserSelectionManager,
+                userTracker = userTracker,
                 legacySettingSyncer =
                     KeyguardQuickAffordanceLegacySettingSyncer(
                         scope = scope,
                         backgroundDispatcher = IMMEDIATE,
                         secureSettings = FakeSettings(),
-                        selectionsManager = selectionManager,
+                        selectionsManager = localUserSelectionManager,
                     ),
                 configs = setOf(config1, config2),
                 dumpManager = mock(),
+                userHandle = UserHandle.SYSTEM,
             )
     }
 
@@ -187,7 +225,53 @@
             )
     }
 
-    private suspend fun assertSelections(
+    @Test
+    fun `selections for secondary user`() =
+        runBlocking(IMMEDIATE) {
+            userTracker.set(
+                userInfos =
+                    listOf(
+                        UserInfo(
+                            UserHandle.USER_SYSTEM,
+                            "Primary",
+                            /* flags= */ 0,
+                        ),
+                        UserInfo(
+                            SECONDARY_USER_1,
+                            "Secondary 1",
+                            /* flags= */ 0,
+                        ),
+                        UserInfo(
+                            SECONDARY_USER_2,
+                            "Secondary 2",
+                            /* flags= */ 0,
+                        ),
+                    ),
+                selectedUserIndex = 2,
+            )
+            client2.insertSelection(
+                slotId = KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_START,
+                affordanceId = FakeKeyguardQuickAffordanceProviderClient.AFFORDANCE_2,
+            )
+            val observed = mutableListOf<Map<String, List<KeyguardQuickAffordanceConfig>>>()
+            val job = underTest.selections.onEach { observed.add(it) }.launchIn(this)
+            yield()
+
+            assertSelections(
+                observed = observed.last(),
+                expected =
+                    mapOf(
+                        KeyguardQuickAffordanceSlots.SLOT_ID_BOTTOM_START to
+                            listOf(
+                                config2,
+                            ),
+                    )
+            )
+
+            job.cancel()
+        }
+
+    private fun assertSelections(
         observed: Map<String, List<KeyguardQuickAffordanceConfig>>?,
         expected: Map<String, List<KeyguardQuickAffordanceConfig>>,
     ) {
@@ -201,5 +285,7 @@
 
     companion object {
         private val IMMEDIATE = Dispatchers.Main.immediate
+        private const val SECONDARY_USER_1 = UserHandle.MIN_SECONDARY_USER_ID + 1
+        private const val SECONDARY_USER_2 = UserHandle.MIN_SECONDARY_USER_ID + 2
     }
 }
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorParameterizedTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorParameterizedTest.kt
index ba7c40b..1c1f039 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorParameterizedTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorParameterizedTest.kt
@@ -18,6 +18,7 @@
 package com.android.systemui.keyguard.domain.interactor
 
 import android.content.Intent
+import android.os.UserHandle
 import androidx.test.filters.SmallTest
 import com.android.internal.widget.LockPatternUtils
 import com.android.systemui.SysuiTestCase
@@ -29,9 +30,11 @@
 import com.android.systemui.flags.Flags
 import com.android.systemui.keyguard.data.quickaffordance.BuiltInKeyguardQuickAffordanceKeys
 import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceConfig
+import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceProviderClientFactory
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceConfig
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLegacySettingSyncer
-import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLocalUserSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceRemoteUserSelectionManager
 import com.android.systemui.keyguard.data.repository.FakeKeyguardRepository
 import com.android.systemui.keyguard.data.repository.KeyguardQuickAffordanceRepository
 import com.android.systemui.keyguard.domain.quickaffordance.FakeKeyguardQuickAffordanceRegistry
@@ -237,8 +240,8 @@
         val qrCodeScanner =
             FakeKeyguardQuickAffordanceConfig(BuiltInKeyguardQuickAffordanceKeys.QR_CODE_SCANNER)
         val scope = CoroutineScope(IMMEDIATE)
-        val selectionManager =
-            KeyguardQuickAffordanceSelectionManager(
+        val localUserSelectionManager =
+            KeyguardQuickAffordanceLocalUserSelectionManager(
                 context = context,
                 userFileManager =
                     mock<UserFileManager>().apply {
@@ -254,20 +257,30 @@
                 userTracker = userTracker,
                 broadcastDispatcher = fakeBroadcastDispatcher,
             )
+        val remoteUserSelectionManager =
+            KeyguardQuickAffordanceRemoteUserSelectionManager(
+                scope = scope,
+                userTracker = userTracker,
+                clientFactory = FakeKeyguardQuickAffordanceProviderClientFactory(userTracker),
+                userHandle = UserHandle.SYSTEM,
+            )
         val quickAffordanceRepository =
             KeyguardQuickAffordanceRepository(
                 appContext = context,
                 scope = scope,
-                selectionManager = selectionManager,
+                localUserSelectionManager = localUserSelectionManager,
+                remoteUserSelectionManager = remoteUserSelectionManager,
+                userTracker = userTracker,
                 legacySettingSyncer =
                     KeyguardQuickAffordanceLegacySettingSyncer(
                         scope = scope,
                         backgroundDispatcher = IMMEDIATE,
                         secureSettings = FakeSettings(),
-                        selectionsManager = selectionManager,
+                        selectionsManager = localUserSelectionManager,
                     ),
                 configs = setOf(homeControls, quickAccessWallet, qrCodeScanner),
                 dumpManager = mock(),
+                userHandle = UserHandle.SYSTEM,
             )
         underTest =
             KeyguardQuickAffordanceInteractor(
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorTest.kt
index 8d0c4ef..11fe905 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/domain/interactor/KeyguardQuickAffordanceInteractorTest.kt
@@ -17,6 +17,7 @@
 
 package com.android.systemui.keyguard.domain.interactor
 
+import android.os.UserHandle
 import androidx.test.filters.SmallTest
 import com.android.internal.widget.LockPatternUtils
 import com.android.systemui.SysuiTestCase
@@ -26,9 +27,11 @@
 import com.android.systemui.flags.Flags
 import com.android.systemui.keyguard.data.quickaffordance.BuiltInKeyguardQuickAffordanceKeys
 import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceConfig
+import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceProviderClientFactory
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceConfig
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLegacySettingSyncer
-import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLocalUserSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceRemoteUserSelectionManager
 import com.android.systemui.keyguard.data.repository.FakeKeyguardRepository
 import com.android.systemui.keyguard.data.repository.KeyguardQuickAffordanceRepository
 import com.android.systemui.keyguard.domain.model.KeyguardQuickAffordanceModel
@@ -98,8 +101,8 @@
             FakeKeyguardQuickAffordanceConfig(BuiltInKeyguardQuickAffordanceKeys.QR_CODE_SCANNER)
         val scope = CoroutineScope(IMMEDIATE)
 
-        val selectionManager =
-            KeyguardQuickAffordanceSelectionManager(
+        val localUserSelectionManager =
+            KeyguardQuickAffordanceLocalUserSelectionManager(
                 context = context,
                 userFileManager =
                     mock<UserFileManager>().apply {
@@ -115,20 +118,30 @@
                 userTracker = userTracker,
                 broadcastDispatcher = fakeBroadcastDispatcher,
             )
+        val remoteUserSelectionManager =
+            KeyguardQuickAffordanceRemoteUserSelectionManager(
+                scope = scope,
+                userTracker = userTracker,
+                clientFactory = FakeKeyguardQuickAffordanceProviderClientFactory(userTracker),
+                userHandle = UserHandle.SYSTEM,
+            )
         val quickAffordanceRepository =
             KeyguardQuickAffordanceRepository(
                 appContext = context,
                 scope = scope,
-                selectionManager = selectionManager,
+                localUserSelectionManager = localUserSelectionManager,
+                remoteUserSelectionManager = remoteUserSelectionManager,
+                userTracker = userTracker,
                 legacySettingSyncer =
                     KeyguardQuickAffordanceLegacySettingSyncer(
                         scope = scope,
                         backgroundDispatcher = IMMEDIATE,
                         secureSettings = FakeSettings(),
-                        selectionsManager = selectionManager,
+                        selectionsManager = localUserSelectionManager,
                     ),
                 configs = setOf(homeControls, quickAccessWallet, qrCodeScanner),
                 dumpManager = mock(),
+                userHandle = UserHandle.SYSTEM,
             )
         featureFlags =
             FakeFeatureFlags().apply {
diff --git a/packages/SystemUI/tests/src/com/android/systemui/keyguard/ui/viewmodel/KeyguardBottomAreaViewModelTest.kt b/packages/SystemUI/tests/src/com/android/systemui/keyguard/ui/viewmodel/KeyguardBottomAreaViewModelTest.kt
index 32849cd..83a5d0e 100644
--- a/packages/SystemUI/tests/src/com/android/systemui/keyguard/ui/viewmodel/KeyguardBottomAreaViewModelTest.kt
+++ b/packages/SystemUI/tests/src/com/android/systemui/keyguard/ui/viewmodel/KeyguardBottomAreaViewModelTest.kt
@@ -17,6 +17,7 @@
 package com.android.systemui.keyguard.ui.viewmodel
 
 import android.content.Intent
+import android.os.UserHandle
 import androidx.test.filters.SmallTest
 import com.android.internal.widget.LockPatternUtils
 import com.android.systemui.SysuiTestCase
@@ -27,9 +28,11 @@
 import com.android.systemui.flags.Flags
 import com.android.systemui.keyguard.data.quickaffordance.BuiltInKeyguardQuickAffordanceKeys
 import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceConfig
+import com.android.systemui.keyguard.data.quickaffordance.FakeKeyguardQuickAffordanceProviderClientFactory
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceConfig
 import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLegacySettingSyncer
-import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceLocalUserSelectionManager
+import com.android.systemui.keyguard.data.quickaffordance.KeyguardQuickAffordanceRemoteUserSelectionManager
 import com.android.systemui.keyguard.data.repository.FakeKeyguardRepository
 import com.android.systemui.keyguard.data.repository.KeyguardQuickAffordanceRepository
 import com.android.systemui.keyguard.domain.interactor.KeyguardBottomAreaInteractor
@@ -121,8 +124,8 @@
         whenever(lockPatternUtils.getStrongAuthForUser(anyInt()))
             .thenReturn(LockPatternUtils.StrongAuthTracker.STRONG_AUTH_NOT_REQUIRED)
         val scope = CoroutineScope(IMMEDIATE)
-        val selectionManager =
-            KeyguardQuickAffordanceSelectionManager(
+        val localUserSelectionManager =
+            KeyguardQuickAffordanceLocalUserSelectionManager(
                 context = context,
                 userFileManager =
                     mock<UserFileManager>().apply {
@@ -138,17 +141,26 @@
                 userTracker = userTracker,
                 broadcastDispatcher = fakeBroadcastDispatcher,
             )
+        val remoteUserSelectionManager =
+            KeyguardQuickAffordanceRemoteUserSelectionManager(
+                scope = scope,
+                userTracker = userTracker,
+                clientFactory = FakeKeyguardQuickAffordanceProviderClientFactory(userTracker),
+                userHandle = UserHandle.SYSTEM,
+            )
         val quickAffordanceRepository =
             KeyguardQuickAffordanceRepository(
                 appContext = context,
                 scope = scope,
-                selectionManager = selectionManager,
+                localUserSelectionManager = localUserSelectionManager,
+                remoteUserSelectionManager = remoteUserSelectionManager,
+                userTracker = userTracker,
                 legacySettingSyncer =
                     KeyguardQuickAffordanceLegacySettingSyncer(
                         scope = scope,
                         backgroundDispatcher = IMMEDIATE,
                         secureSettings = FakeSettings(),
-                        selectionsManager = selectionManager,
+                        selectionsManager = localUserSelectionManager,
                     ),
                 configs =
                     setOf(
@@ -157,6 +169,7 @@
                         qrCodeScannerAffordanceConfig,
                     ),
                 dumpManager = mock(),
+                userHandle = UserHandle.SYSTEM,
             )
         underTest =
             KeyguardBottomAreaViewModel(
diff --git a/packages/SystemUI/tests/utils/src/com/android/systemui/keyguard/data/quickaffordance/FakeKeyguardQuickAffordanceProviderClientFactory.kt b/packages/SystemUI/tests/utils/src/com/android/systemui/keyguard/data/quickaffordance/FakeKeyguardQuickAffordanceProviderClientFactory.kt
new file mode 100644
index 0000000..d85dd2e
--- /dev/null
+++ b/packages/SystemUI/tests/utils/src/com/android/systemui/keyguard/data/quickaffordance/FakeKeyguardQuickAffordanceProviderClientFactory.kt
@@ -0,0 +1,34 @@
+/*
+ * Copyright (C) 2022 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.keyguard.data.quickaffordance
+
+import com.android.systemui.settings.UserTracker
+import com.android.systemui.shared.quickaffordance.data.content.FakeKeyguardQuickAffordanceProviderClient
+import com.android.systemui.shared.quickaffordance.data.content.KeyguardQuickAffordanceProviderClient
+
+class FakeKeyguardQuickAffordanceProviderClientFactory(
+    private val userTracker: UserTracker,
+    private val callback: (Int) -> KeyguardQuickAffordanceProviderClient = {
+        FakeKeyguardQuickAffordanceProviderClient()
+    },
+) : KeyguardQuickAffordanceProviderClientFactory {
+
+    override fun create(): KeyguardQuickAffordanceProviderClient {
+        return callback(userTracker.userId)
+    }
+}
diff --git a/packages/SystemUI/tests/utils/src/com/android/systemui/settings/FakeUserTracker.kt b/packages/SystemUI/tests/utils/src/com/android/systemui/settings/FakeUserTracker.kt
index a7eadba..0dd1fc7 100644
--- a/packages/SystemUI/tests/utils/src/com/android/systemui/settings/FakeUserTracker.kt
+++ b/packages/SystemUI/tests/utils/src/com/android/systemui/settings/FakeUserTracker.kt
@@ -66,7 +66,8 @@
         _userId = _userInfo.id
         _userHandle = UserHandle.of(_userId)
 
-        callbacks.forEach { it.onUserChanged(_userId, userContext) }
+        val copy = callbacks.toList()
+        copy.forEach { it.onUserChanged(_userId, userContext) }
     }
 
     fun onProfileChanged() {