如果屏幕锁定，单击暂停按钮时，avplayer 不会暂停

Question

如果应用正在播放音频并且手机屏幕被锁定，则控制屏幕如下所示。我无法对 avplayer 采取任何行动

在我的 appdelegate 中我实现了：

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions {
    MPRemoteCommandCenter *rcc = [MPRemoteCommandCenter sharedCommandCenter];
[[rcc skipForwardCommand] setEnabled:NO];
[[rcc skipBackwardCommand] setEnabled:NO];
[[rcc nextTrackCommand] setEnabled:NO];
[[rcc previousTrackCommand] setEnabled:NO];
[[rcc skipForwardCommand] setEnabled:NO];
[[rcc skipBackwardCommand] setEnabled:NO];
rcc.playCommand.enabled = YES;
rcc.pauseCommand.enabled = YES;
[[MPRemoteCommandCenter sharedCommandCenter].playCommand addTarget:self action:@selector(play)];
[[MPRemoteCommandCenter sharedCommandCenter].pauseCommand addTarget:self action:@selector(pause)];
}

- (void) play {
[[MyVideoController instance] play];
}

- (void) pause {
[[MyVideoController instance] pause];
}

MyVideoController 类包括：

- (void) pause {
    [self.avPlayer pause];
}

- (void) play {
    [self.avPlayer play];
}

即使触发了这些方法（添加了断点进行检查），也不会对 avplayer 执行任何操作。无论如何，avplayer 不会暂停。

有什么办法可以暂停avplayer吗？

编辑 1： 添加完整代码

在我的 AppDelegate 中：

- (void) remoteControlReceivedWithEvent: (UIEvent *) event {
[[ZVideoPlayerController instance] eventReceived:event];
if (event.type == UIEventTypeRemoteControl) {
    switch (event.subtype) {
        case UIEventSubtypeRemoteControlTogglePlayPause: {

            break;
        }
        case UIEventSubtypeRemoteControlPlay: {
            [[ZVideoPlayerController instance] play];
            break;
        }
        case UIEventSubtypeRemoteControlPause: {
            [[ZVideoPlayerController instance] pause];
            break;
        }
        default:
            break;
    }
}

}

- (void)applicationDidEnterBackground:(UIApplication *)application {
[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
[self becomeFirstResponder];
}

- (void)applicationDidBecomeActive:(UIApplication *)application {
[[UIApplication sharedApplication] endReceivingRemoteControlEvents];
}

我正在接收事件，但在 AVPLAYER 上调用暂停方法后音频没有暂停。

编辑 2： PlayerController 类中的实例声明

+ (instancetype)instance {
static id instance = nil;
if (instance == nil)
{
    static dispatch_once_t onceToken = 0;
    dispatch_once(&onceToken, ^(void) {
        NSAssert(instance == nil, @"Singleton instance is already allocated.");
        instance = [[super allocWithZone:NULL] init];
    });
}
return instance;
}

初始化 AVPlayer

    AVURLAsset *avAsset = [AVURLAsset URLAssetWithURL:url options:nil];
AVPlayerItem *playerItem = [AVPlayerItem playerItemWithAsset:avAsset];
AVAudioSession *session = [AVAudioSession sharedInstance];
[session setCategory:AVAudioSessionCategoryPlayback error:nil];
NSError *activationError = nil;
BOOL success = [[AVAudioSession sharedInstance] setActive: YES error: &activationError];

NSMutableDictionary *songInfo = [[NSMutableDictionary alloc] init];

MPMediaItemArtwork *albumArt = [[MPMediaItemArtwork alloc] initWithImage: [UIImage imageNamed:@"Audio_Thumbnail_Play"]];
[songInfo setObject:title forKey:MPMediaItemPropertyTitle];
[songInfo setObject:@"100" forKey:MPMediaItemPropertyPlaybackDuration];
[songInfo setObject:albumArt forKey:MPMediaItemPropertyArtwork];
[[MPNowPlayingInfoCenter defaultCenter] setNowPlayingInfo:songInfo];
self.avPlayer = [AVPlayer playerWithPlayerItem:playerItem];
self.avPlayerLayer = [AVPlayerLayer playerLayerWithPlayer:self.avPlayer];

Answer 1

我找到了解决问题的方法。当我得到 avPlayer 的 nil 值时，我使用我的 PageViewController 类来获取 PlayerController 的实例。然后我使用这个 playerController 的实例来播放和暂停我的 avplayer，因为这个实例持有对 avPlayer 的引用。

- (PlayerController *)getVideoController {
NSArray *controllers = [UtiliyClass getNavigationController].viewControllers;
PageViewController *pageController = nil;
for (UIViewController *cont in controllers) {
    if ([cont isKindOfClass:[PageViewController class]]) {
        pageController = (PageViewController *)cont;
        break;
    }
}
if (pageController == nil) {
    return nil;
}
NSArray *objectsController =pageController.pageController.viewControllers;
PlayerController *videoPlayerController = nil;
for (UIViewController *item in objectsController) {
    if ([item isKindOfClass:[PlayerController class]]) {
        videoPlayerController = (PlayerController *)item;
        break;
    }
}
return videoPlayerController;
}

- (void) pause {
PlayerController *controller = [self getVideoController];
[controller.avPlayer pause];
}

- (void) play {
PlayerController *controller = [self getVideoController];
[controller.avPlayer play];
}

Answer 2

当应用程序被锁定时，您需要注册远程通知以更新播放器状态。如下：

在你的 AppDelegate 中添加这个，最好是在 applicationDidEnterBackground:

[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
[self becomeFirstResponder];

这在 applicationDidBecomeActive:

[[UIApplication sharedApplication] endReceivingRemoteControlEvents];

通过在 AppDelagate 中添加它来接收远程通知。这将在手机锁定时侦听所有操作。

- (void)remoteControlReceivedWithEvent:(UIEvent *)event {
    if (event.type == UIEventTypeRemoteControl){
        // Call method of your player where you want to make change (Pause , Paly),
        // I am calling a shared view for example, Its up to your logic how you want to deal it
      [[AudioPlayerView sharedPlayerView] remoteControlReceivedWithEvent:event];


    }
 }

然后得到你想要的事件并相应地更新状态

 - (void)remoteControlReceivedWithEvent:(UIEvent *)event {

       if (event.type == UIEventTypeRemoteControl){
           switch (event.subtype){
               case UIEventSubtypeRemoteControlPlay:
                    [[MyVideoController instance] play];
                     break;
               case UIEventSubtypeRemoteControlPause:
                    [[MyVideoController instance] pause];
                    break;

               case UIEventSubtypeRemoteControlTogglePlayPause:
                   // Check if state is playing , call pause else call play
                    break;
                }
        default:
            break;
        }
     }
 }

Answer 3

在 iOS 7.1 及更高版本中，使用共享的 MPRemoteCommandCenter 对象来注册远程控制事件。使用共享命令中心对象时无需调用此方法。 此方法使用响应者链启动远程控制事件的传递。远程控制事件源自耳机和外部附件发出的命令，旨在控制应用程序呈现的多媒体。要停止接收远程控制事件，您必须调用 endReceivingRemoteControlEvents()。

在 didfinishlunching 中为 init audio season 添加以下代码并获取远程控制事件：

        // Initialize the AVAudioSession here.
        if (![[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:&myErr]) {
            // Handle the error here.
            NSLog(@"Audio Session error %@, %@", myErr, [myErr userInfo]);
        }
        else{
            // Since there were no errors initializing the session, we'll allow begin receiving remote control events
            [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];
        }

要接收命令，请使用此代码：

- (void)remoteControlReceivedWithEvent:(UIEvent *)receivedEvent {

    if (receivedEvent.type == UIEventTypeRemoteControl) {

        switch (receivedEvent.subtype) {

            case UIEventSubtypeRemoteControlPreviousTrack:

                break;

            case UIEventSubtypeRemoteControlNextTrack:

                break;

            case UIEventSubtypeRemoteControlPlay:
                [[MyVideoController instance] play];
                break;

            case UIEventSubtypeRemoteControlPause:
                [[MyVideoController instance] pause];
                break;

            default:
                break;
        }
    }
}