1 /*
2  * Copyright (C) 2024 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 package com.android.settingslib.media.session
18 
19 import android.media.session.MediaController
20 import android.media.session.MediaSession
21 import android.media.session.MediaSessionManager
22 import android.os.UserHandle
23 import androidx.concurrent.futures.DirectExecutor
24 import kotlinx.coroutines.channels.Channel
25 import kotlinx.coroutines.channels.awaitClose
26 import kotlinx.coroutines.flow.Flow
27 import kotlinx.coroutines.flow.buffer
28 import kotlinx.coroutines.flow.callbackFlow
29 import kotlinx.coroutines.launch
30 
31 /** [Flow] for [MediaSessionManager.OnActiveSessionsChangedListener]. */
32 val MediaSessionManager.activeMediaChanges: Flow<List<MediaController>?>
33     get() =
<lambda>null34         callbackFlow {
35                 val listener =
36                     MediaSessionManager.OnActiveSessionsChangedListener { launch { send(it) } }
37                 addOnActiveSessionsChangedListener(
38                     null,
39                     UserHandle.of(UserHandle.myUserId()),
40                     DirectExecutor.INSTANCE,
41                     listener,
42                 )
43                 awaitClose { removeOnActiveSessionsChangedListener(listener) }
44             }
45             .buffer(capacity = Channel.CONFLATED)
46 
47 /** [Flow] for [MediaSessionManager.RemoteSessionCallback]. */
48 val MediaSessionManager.defaultRemoteSessionChanged: Flow<MediaSession.Token?>
49     get() =
<lambda>null50         callbackFlow {
51                 val callback =
52                     object : MediaSessionManager.RemoteSessionCallback {
53                         override fun onVolumeChanged(sessionToken: MediaSession.Token, flags: Int) =
54                             Unit
55 
56                         override fun onDefaultRemoteSessionChanged(
57                             sessionToken: MediaSession.Token?
58                         ) {
59                             launch { send(sessionToken) }
60                         }
61                     }
62                 registerRemoteSessionCallback(DirectExecutor.INSTANCE, callback)
63                 awaitClose { unregisterRemoteSessionCallback(callback) }
64             }
65             .buffer(capacity = Channel.CONFLATED)
66