From 43d75385149b2a941538da277a21b390fc764904 Mon Sep 17 00:00:00 2001
From: Santiago Seifert <aquilescanta@google.com>
Date: Tue, 27 Sep 2022 11:22:53 +0000
Subject: [PATCH] Use UserSwitchObserver to detect switches in the running user

The current implementation relies on listening for
Intent.ACTION_USER_SWITCHED, which can take more than 30
seconds to propagate, making UserSwitchObserver a more
reliable option.

Bug: 242188673
Test: atest mediaroutertest CtsMediaBetterTogetherTestCases
Test: Manually tested casting on secondary users.
Test: Pending CL to verify route availability on secondary users as part of the linked bug.
Change-Id: I67765a671bce590495b73ef7df6bf72ba3c9f03a
---
 .../server/media/MediaRouter2ServiceImpl.java |  5 +--
 .../server/media/MediaRouterService.java      | 40 ++++++++++++-------
 2 files changed, 27 insertions(+), 18 deletions(-)

diff --git a/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java b/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java
index 82b5c11cfb8ca..cc8761d705309 100644
--- a/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java
+++ b/services/core/java/com/android/server/media/MediaRouter2ServiceImpl.java
@@ -621,10 +621,9 @@ class MediaRouter2ServiceImpl {
         }
     }
 
-    //TODO(b/136703681): Review this is handling multi-user properly.
-    void switchUser() {
+    // TODO(b/136703681): Review this is handling multi-user properly.
+    void switchUser(int userId) {
         synchronized (mLock) {
-            int userId = ActivityManager.getCurrentUser();
             if (mCurrentUserId != userId) {
                 final int oldUserId = mCurrentUserId;
                 mCurrentUserId = userId; // do this first
diff --git a/services/core/java/com/android/server/media/MediaRouterService.java b/services/core/java/com/android/server/media/MediaRouterService.java
index 4f0da79528679..d7d0b42aa0a7c 100644
--- a/services/core/java/com/android/server/media/MediaRouterService.java
+++ b/services/core/java/com/android/server/media/MediaRouterService.java
@@ -17,7 +17,9 @@
 package com.android.server.media;
 
 import android.annotation.NonNull;
+import android.annotation.RequiresPermission;
 import android.app.ActivityManager;
+import android.app.UserSwitchObserver;
 import android.bluetooth.BluetoothA2dp;
 import android.bluetooth.BluetoothDevice;
 import android.content.BroadcastReceiver;
@@ -146,18 +148,27 @@ public final class MediaRouterService extends IMediaRouterService.Stub
         context.registerReceiverAsUser(mReceiver, UserHandle.ALL, intentFilter, null, null);
     }
 
-    public void systemRunning() {
-        IntentFilter filter = new IntentFilter(Intent.ACTION_USER_SWITCHED);
-        mContext.registerReceiver(new BroadcastReceiver() {
-            @Override
-            public void onReceive(Context context, Intent intent) {
-                if (intent.getAction().equals(Intent.ACTION_USER_SWITCHED)) {
-                    switchUser();
-                }
-            }
-        }, filter);
-
-        switchUser();
+    /**
+     * Initializes the MediaRouter service.
+     *
+     * @throws RemoteException If an error occurs while registering the {@link UserSwitchObserver}.
+     */
+    @RequiresPermission(
+            anyOf = {
+                "android.permission.INTERACT_ACROSS_USERS",
+                "android.permission.INTERACT_ACROSS_USERS_FULL"
+            })
+    public void systemRunning() throws RemoteException {
+        ActivityManager.getService()
+                .registerUserSwitchObserver(
+                        new UserSwitchObserver() {
+                            @Override
+                            public void onUserSwitchComplete(int newUserId) {
+                                switchUser(newUserId);
+                            }
+                        },
+                        TAG);
+        switchUser(ActivityManager.getCurrentUser());
     }
 
     @Override
@@ -634,9 +645,8 @@ public final class MediaRouterService extends IMediaRouterService.Stub
         }
     }
 
-    void switchUser() {
+    void switchUser(int userId) {
         synchronized (mLock) {
-            int userId = ActivityManager.getCurrentUser();
             if (mCurrentUserId != userId) {
                 final int oldUserId = mCurrentUserId;
                 mCurrentUserId = userId; // do this first
@@ -653,7 +663,7 @@ public final class MediaRouterService extends IMediaRouterService.Stub
                 }
             }
         }
-        mService2.switchUser();
+        mService2.switchUser(userId);
     }
 
     void clientDied(ClientRecord clientRecord) {