AVPlayer视频播放的使用简介

本文主要是介绍AVPlayer视频播放的使用简介，希望对大家解决编程问题提供一定的参考价值，需要的开发者们随着小编来一起学习吧！

首先我们定义变量：

    NSTimeInterval totalDration;

@property (strong, nonatomic) AVPlayer *player;
@property (retain, nonatomic) AVPlayerItem *playerItem;
@property (retain, nonatomic) id playbackTimeObserver;

而AVPlayer的使用离不开AVPlayerLayer，因此我们需要设置如下：

+ (Class)layerClass {return [AVPlayerLayer class];
}- (AVPlayer *)player {return [(AVPlayerLayer *)[self layer] player];
}- (void)setPlayer:(AVPlayer *)player {[(AVPlayerLayer *)[self layer] setPlayer:player];
}

视频播放的初始化

        self.playerItem = [[[AVPlayerItem alloc]initWithURL:_videoURL] autorelease];[self.playerItem addObserver:self forKeyPath:@"status" options:NSKeyValueObservingOptionNew context:nil];[self.playerItem addObserver:self forKeyPath:@"loadedTimeRanges" options:NSKeyValueObservingOptionNew context:nil];self.player = [[[AVPlayer alloc]initWithPlayerItem:self.playerItem] autorelease];[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(videoPlayDidEnd:) name:AVPlayerItemDidPlayToEndTimeNotification object:self.playerItem];[(AVPlayerLayer*)[self layer] setVideoGravity:AVLayerVideoGravityResizeAspect];

添加的observer可以监控缓存进度及播放进度

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context {AVPlayerItem *playerItem = (AVPlayerItem *)object;if ([keyPath isEqualToString:@"status"]) {if ([playerItem status] == AVPlayerStatusReadyToPlay) {// ready to playNSLog(@"AVPlayerStatusReadyToPlay");CMTime duration = self.playerItem.duration;// 获取视频总长度totalDration = playerItem.duration.value / playerItem.duration.timescale;// 转换成秒// 可以更新视频总长度if (_didEnterFullScreenMode  && !_is_s_video) {[self monitoringPlayback:self.playerItem];// 监听播放状态}}else if ([playerItem status] == AVPlayerStatusFailed) {NSLog(@"AVPlayerStatusFailed");// 播放失败的处理}}else if ([keyPath isEqualToString:@"loadedTimeRanges"]) {NSTimeInterval timeInterval = [self availableDuration];// 计算缓冲进度CMTime duration = self.playerItem.duration;CGFloat totalDuration = CMTimeGetSeconds(duration);// 更新缓存进度}
}

- (void)monitoringPlayback:(AVPlayerItem *)playerItem {self.playbackTimeObserver = [self.player addPeriodicTimeObserverForInterval:CMTimeMake(1, 1) queue:NULL usingBlock:^(CMTime time) {CGFloat currentSecond = playerItem.currentTime.value/playerItem.currentTime.timescale;// 计算当前在第几秒// 更新播放进度}];}

需要注意的是playerItem销毁前一定先移除observer

        [self.playerItem removeObserver:self forKeyPath:@"status"];[self.playerItem removeObserver:self forKeyPath:@"loadedTimeRanges"];

通过slide或者其他方式改变播放进度：

    CGFloat value = progressView.progressValue;CGFloat curTime = value * totalDration;CMTime time = CMTimeMake(curTime, 1);[self.player pause]；[self.player seekToTime:time completionHandler:^(BOOL f){[self.player play];}];

在完成了视频播放，经过尝试需要设置如下才可以继续播放：

    // 初始化值[self.playerItem setReversePlaybackEndTime:kCMTimeZero];[self.playerItem seekToTime:kCMTimeZero];

关于视频播放音量的设置，如下：

- (void) setVolome:(CGFloat) volome {if (self.playerItem == nil) {return;}if (volome > 1) {volome = 1;}if (volome < 0) {volome = 0;}NSArray *audioTracks = [_playerItem.asset tracksWithMediaType:AVMediaTypeAudio];NSMutableArray *allAudioParams = [NSMutableArray array];for (AVAssetTrack *track in audioTracks) {AVMutableAudioMixInputParameters *audioInputParams =[AVMutableAudioMixInputParameters audioMixInputParameters];[audioInputParams setVolume:volome atTime:kCMTimeZero];[audioInputParams setTrackID:[track trackID]];[allAudioParams addObject:audioInputParams];}AVMutableAudioMix *audioMix = [AVMutableAudioMix audioMix];[audioMix setInputParameters:allAudioParams];[_playerItem setAudioMix:audioMix];
}