AVQueuePlayer 在线播放一组网络音频文件

柔情只为你懂 2022-06-08 02:55 158阅读 0赞

头文件

@interface ZNAudioPlayerUtil : NSObject

//播放一组网络音频文件  
\+ (void)playAudios:(NSArray\*)audioArr;  
//终止播放  
\+ (void)stopPlayer;  
//暂停播放  
\+ (void)pausePlayer;  
//恢复播放  
\+ (void)resumePlayer;  
//拖动到某个时间点  
\+ (void)seekToTime:(CMTime)time;  
//当前播放时间  
\+ (CGFloat)currentTime;  
//总时长  
\+ (CGFloat)totalTime;

@end

static void\* const AVLoopPlayerQueuePlayerStatusObservationContext = (void\*)&AVLoopPlayerQueuePlayerStatusObservationContext;  
static void\* const AVLoopPlayerCurrentItemObservationContext = (void\*)&AVLoopPlayerCurrentItemObservationContext;  
static void\* const AVLoopPlayerCurrentItemStatusObservationContext = (void\*)&AVLoopPlayerCurrentItemStatusObservationContext;

@interface ZNAudioPlayerUtil()\{  
BOOL \_addedObservers;  
\}

@property (nonatomic, strong) AVQueuePlayer \*queuePlayer;  
@property (nonatomic, assign) CGFloat totalDuration;

*  (void)playbackInLoopWithURL:(NSString \*)urlStr;
 *  (void)stopPlayback;

@end

@implementation ZNAudioPlayerUtil

*  (instancetype)shareInstance\{  
    static ZNAudioPlayerUtil \*player = nil;  
    static dispatch\_once\_t onceToken;  
    dispatch\_once(&onceToken, ^\{  
    player = \[\[ZNAudioPlayerUtil alloc\]init\];  
    \});  
    return player;  
    \}
 *  (void)playAudios:(NSArray \*)audioArr\{  
    \[\[ZNAudioPlayerUtil shareInstance\] stopPlayback\];  
    for (NSString \*audioID in audioArr) \{  
    NSString \*urlStr = \[NSString stringWithFormat:@”%@%@?id=%@”,EvHRServerHost,kHR\_DownloadAudioFileUrl,audioID\];  
    \[\[ZNAudioPlayerUtil shareInstance\] playbackInLoopWithURL:urlStr\];  
    \}  
    \}
 *  (void)stopPlayer\{  
    \[\[ZNAudioPlayerUtil shareInstance\] stopPlayback\];  
    \}
 *  (instancetype)init\{  
    if (self = \[super init\]) \{  
    \_queuePlayer = \[\[AVQueuePlayer alloc\]init\];  
    \}  
    return self;

*  (void)startObservingPlayerAndItem  
    \{  
    if (\_addedObservers == NO)  
    \{  
    \[\_queuePlayer addObserver:self forKeyPath:@”status” options:NSKeyValueObservingOptionNew context:AVLoopPlayerQueuePlayerStatusObservationContext\];  
    \[\_queuePlayer addObserver:self forKeyPath:@”currentItem” options:NSKeyValueObservingOptionOld context:AVLoopPlayerCurrentItemObservationContext\];  
    \[\_queuePlayer addObserver:self forKeyPath:@”currentItem.status” options:NSKeyValueObservingOptionNew context:AVLoopPlayerCurrentItemStatusObservationContext\];  
    \_addedObservers = YES;  
    \}  
    \}
 *  (void)stopObservingPlayerAndItem  
    \{  
    if (\_addedObservers)  
    \{  
    \[\_queuePlayer removeObserver:self forKeyPath:@”status” context:AVLoopPlayerQueuePlayerStatusObservationContext\];  
    \[\_queuePlayer removeObserver:self forKeyPath:@”currentItem” context:AVLoopPlayerCurrentItemObservationContext\];  
    \[\_queuePlayer removeObserver:self forKeyPath:@”currentItem.status” context:AVLoopPlayerCurrentItemStatusObservationContext\];  
    \_addedObservers = NO;  
    \}  
    \}
 *  (void)playbackInLoopWithURL:(NSString \*)urlStr  
    \{  
    AVURLAsset \*asset = \[AVURLAsset assetWithURL:\[NSURL URLWithString:urlStr\]\];
    
    \[asset loadValuesAsynchronouslyForKeys:@\[@”duration”, @”playable”\] completionHandler:^\{  
    /\*  
    The asset invokes its completion handler on an arbitrary queue when  
    loading is complete. Because we want to access our AVQueuePlayer in our  
    ensuing set-up, we must dispatch our handler to the main queue.  
    \*/  
    dispatch\_async(dispatch\_get\_main\_queue(), ^\{  
    NSError \*durationError, \*playableError;  
    /\*  
    Check to make sure duration and playable properties are loaded  
    before accessing them.  
    \*/  
    AVKeyValueStatus durationStatus = \[asset statusOfValueForKey:@”duration” error:&durationError\];  
    AVKeyValueStatus playableStatus = \[asset statusOfValueForKey:@”playable” error:&playableError\];
    
        if (durationStatus == AVKeyValueStatusLoaded && playableStatus == AVKeyValueStatusLoaded )
            {
                if (CMTIME_COMPARE_INLINE([asset duration], >=, CMTimeMake(1,100)) && [asset isPlayable])
                {
                    /*
                     Based on the duration of the asset, we decide the number of
                     player items to add to demonstrate gapless playback of the
                     same asset.
                     */
                    NSUInteger countOfPlayerItems = (1.0 / CMTimeGetSeconds([asset duration])) + 2;
    
    // for (NSUInteger idx = 0; idx < countOfPlayerItems; ++idx)  
    \{  
    AVPlayerItem \*playerItem = \[AVPlayerItem playerItemWithAsset:asset\];  
    if (playerItem)  
    \{  
    \[\_queuePlayer insertItem:playerItem afterItem:nil\];  
    \}  
    \}
    
        [self startObservingPlayerAndItem];
                    [_queuePlayer play];
                }
                else
                {
                    NSLog(@"Can't loop. Asset duration too short(%1.3f sec) or not playable(isPlayable: %s)",
                          CMTimeGetSeconds([asset duration]), ([asset isPlayable]?"YES":"NO"));
                }
            }
            else
            {
                if (durationStatus == AVKeyValueStatusFailed)
                    NSLog(@"Failed to load duration property for asset: %@ with error: %@", asset, durationError);
        
                if (playableStatus == AVKeyValueStatusFailed)
                    NSLog(@"Failed to load playable property for asset: %@ with error: %@", asset, playableError);
            }
        });
    
    \}\];  
    \}
 *  (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary* )changeDictionary context:(void \*)context  
    \{  
    return;  
    if (context == AVLoopPlayerQueuePlayerStatusObservationContext)  
    \{  
    AVPlayerStatus newPlayerStatus = (AVPlayerStatus)\[\[changeDictionary objectForKey:NSKeyValueChangeNewKey\] unsignedIntegerValue\];  
    if (newPlayerStatus == AVPlayerStatusFailed) \{  
    AVQueuePlayer *player = (AVQueuePlayer* )object;  
    NSLog(@”End looping since player has failed with error %@”, player.error);  
    \[self stopPlayback\];  
    \}
    
    \}  
    else if (context == AVLoopPlayerCurrentItemObservationContext)  
    \{  
    AVQueuePlayer *player = (AVQueuePlayer* )object;
    
        if ([[player items] count] == 0)
        {
            NSLog(@"Play queue emptied out due to bad player item. End looping.");
            [self stopPlayback];
        }
        else
        {
            // Append the previous current item to the player's queue.
    
    // AVPlayerItem \*itemRemoved = changeDictionary\[NSKeyValueChangeOldKey\];
    
        /*
             An initial change from a nil currentItem yields NSNull here. Check
             to make sure the class is AVPlayerItem before appending it to the
             end of the queue.
             */
    
    // if (\[itemRemoved isKindOfClass:\[AVPlayerItem class\]\])  
    // \{  
    // \[itemRemoved seekToTime:kCMTimeZero\];  
    // \[self stopObservingPlayerAndItem\];  
    // \[player insertItem:itemRemoved afterItem:nil\];  
    // \[self startObservingPlayerAndItem\];  
    // \}  
    \}  
    \}  
    else if (context == AVLoopPlayerCurrentItemStatusObservationContext)  
    \{  
    AVPlayerItemStatus newItemStatus = (AVPlayerItemStatus)\[\[changeDictionary objectForKey:NSKeyValueChangeNewKey\] unsignedIntegerValue\];  
    if (newItemStatus == AVPlayerItemStatusFailed) \{  
    AVQueuePlayer *player = (AVQueuePlayer* )object;  
    NSLog(@”End looping since player item has failed with error %@”, player.currentItem.error);  
    \[self stopPlayback\];  
    \}  
    \}  
    \}
 *  (void)stopPlayback  
    \{  
    \[\_queuePlayer pause\];  
    \[self stopObservingPlayerAndItem\];  
    \[\_queuePlayer removeAllItems\];  
    \}

# pragma mark - public methods #

*  (void)pausePlayer\{  
    AVQueuePlayer \*queuePalyer = \[ZNAudioPlayerUtil shareInstance\].queuePlayer;  
    if (queuePalyer.timeControlStatus == AVPlayerTimeControlStatusPlaying) \{  
    \[queuePalyer pause\];  
    \}  
    \}
 *  (void)resumePlayer\{  
    AVQueuePlayer \*queuePalyer = \[ZNAudioPlayerUtil shareInstance\].queuePlayer;  
    if (queuePalyer.timeControlStatus == AVPlayerTimeControlStatusPaused) \{  
    \[queuePalyer play\];  
    \}  
    \}
 *  (void)seekToTime:(CMTime)time\{  
    AVQueuePlayer \*queuePlayer = \[ZNAudioPlayerUtil shareInstance\].queuePlayer;  
    if (queuePlayer) \{  
    \[queuePlayer seekToTime:time\];  
    \}  
    \}
 *  (CGFloat)currentTime\{  
    AVQueuePlayer \*queuePlayer = \[ZNAudioPlayerUtil shareInstance\].queuePlayer;  
    if (queuePlayer) \{  
    return \[ZNAudioPlayerUtil totalTime\] - CMTimeGetSeconds(queuePlayer.currentItem.currentTime);  
    \}  
    return 0;  
    \}
 *  (CGFloat)totalTime\{  
    AVQueuePlayer \*queuePlayer = \[ZNAudioPlayerUtil shareInstance\].queuePlayer;  
    if (queuePlayer) \{  
    CGFloat totalDuration = 0;  
    for (AVPlayerItem \*item in queuePlayer.items) \{  
    CGFloat duration = CMTimeGetSeconds(item.duration);  
    totalDuration += duration;  
    \}  
    return totalDuration;  
    \}  
    return 0;  
    \}

@end