第三记- Swift版百思不得姐

音频及视频播放：

效果图：

实现思路：

1：利用AVPlayer和AVPlayerItem实现音频播放器，

 let url  = NSURL(string: vocieModel!.voiceuri!)!
        songItem = AVPlayerItem(URL: url)
        player = AVPlayer(playerItem: songItem!)
        player.play()

2：开始播放后获取播放进度，利用 addPeriodicTimeObserverForInterval 方法获取当前播放的音频时间，从服务器获取音频总时长，将比值设置给进度条，这就实现了显示进度条功能

 weak var weakSelf = self
        //监听播放进度 每到一定时间都会回调一次
       PeriodicTime = player.addPeriodicTimeObserverForInterval(CMTimeMake(1, 1), queue:dispatch_get_main_queue()) { (CMTime time) -> Void in
        
        //获取当前秒数
        let current = CMTimeGetSeconds(time);
        let total = CMTimeGetSeconds(weakSelf!.songItem!.duration);
        weakSelf!.progress.setValue(Float(current)/Float(total), animated: true)
        weakSelf!.time.text = NSString(format: "%02ld:%02ld", Int(current)/60,Int(current)%60) as String

        
        
        
        let arr =   (self.songItem!.loadedTimeRanges) as NSArray
            //本次缓冲的时间范围
        let cmTime =  (arr.firstObject?.CMTimeRangeValue)! as CMTimeRange
        //
        let totalBuffer = CMTimeGetSeconds(cmTime.start) + CMTimeGetSeconds(cmTime.duration) as NSTimeInterval //缓冲总长度
        //            progress.
        XYDEBUG("共缓冲\(NSString(format: "%.2f", totalBuffer))")
        

        }

3：监听播放完成的通知

监听的对象就是AVPlayerItem，在相应方法中移除对象，隐藏按钮和正在播放时间

// 监听AVPlayer播放完成通知
        XYNotification.addObserver(self, selector: "playbackFinish:", name: AVPlayerItemDidPlayToEndTimeNotification, object: songItem)

4：拖动进度条

我的进度条就是UISlider控件显示的，这里我是在该控件上添加一个拖动手势

UIPanGestureRecognizer。然后监听手势拖动方法，

    //拖动的时候，计算比例
     func progressVaule(sender: UIGestureRecognizer) {
        
        // 1.获取点击的位置
        let locat =  sender.locationInView(sender.view)
        // 2.获取点击的在slider长度中占据的比例
        let ratio = locat.x / self.progress.bounds.size.width;
        // 3.改变歌曲播放的时间
        let cd = CMTimeGetSeconds(songItem!.duration)
        //音频跳转指定位置
        songItem?.seekToTime(CMTimeMake(Int64(CGFloat(cd) * ratio), 1), completionHandler: { (Bool bool) -> Void in
           self.player.play()
        })
    }

到这就能实现一个音频播放了，

注：AVPlayerItem可以利用KVO机制获取音频加载状态、缓冲状态

代码如下：

//      kvo  媒体加载状态
        songItem!.addObserver(self, forKeyPath: "status", options: .New, context: nil)
//      kvo  数据缓冲状态
        songItem!.addObserver(self, forKeyPath: "loadedTimeRanges", options: .New, context: nil)

//    KVO方法中获取其status的改变
    override func observeValueForKeyPath(keyPath: String?, ofObject object: AnyObject?, change: [String : AnyObject]?, context: UnsafeMutablePointer) {
        
        let songAv = object as? AVPlayerItem
        if (keyPath == "status"){
            switch player.status{
            case .ReadyToPlay :
                XYDEBUG("播放")
                player.play()
                break
            case .Failed :
                XYDEBUG("Failed")
                break
            case .Unknown :
                XYDEBUG("未知状态")
                break
            }
        }else if(keyPath == "loadedTimeRanges"){
            let arr =   (songAv?.loadedTimeRanges)! as NSArray
            //            //本次缓冲的时间范围
            let cmTime =  (arr.firstObject?.CMTimeRangeValue)! as CMTimeRange
            //
            let totalBuffer = CMTimeGetSeconds(cmTime.start) + CMTimeGetSeconds(cmTime.duration) as NSTimeInterval //缓冲总长度
            
//            progress.
            
            XYDEBUG("共缓冲\(NSString(format: "%.2f", totalBuffer))")
        }
    }

视频播放在这里推荐一个三方库KRVideoPlayer