AVPlayer的使用，带缓冲

#import "ViewController.h"

#import <AVFoundation/AVFoundation.h>

@interface ViewController ()

{

    AVPlayer *player;

    AVPlayerItem *playerItem;

    

    UIProgressView * progressView;

    UISlider *_slider;

    

    //推断slider是否按下，

    BOOL isOpen;

}

@end



@implementation ViewController



- (void)viewDidLoad {

    [super viewDidLoad];

    [self createUI];

    //进行初始化创建

    NSURL *url = [NSURL fileURLWithPath:@"/Users/qianfeng01/Downloads/千锋Swift视频教程-1.Swift语言介绍.mp4"];

    playerItem  = [[AVPlayerItem alloc]initWithURL:url];

    //创建player

    player = [[AVPlayer alloc]initWithPlayerItem:playerItem];

    //生成layer层

    AVPlayerLayer *layer = [AVPlayerLayer playerLayerWithPlayer:player];

    //设置坐标

    layer.frame = CGRectMake(0, 0, self.view.frame.size.width, self.view.frame.size.height);

    

    //把layer层假如到self.view.layer中

    [self.view.layer addSublayer:layer];

    //进行播放

    [player play];

    

    /**以上是主要的播放界面。可是没有前进后退**/

    //观察是否播放，KVO进行观察，观察playerItem.status

    [playerItem addObserver:self forKeyPath:@"status" options:NSKeyValueObservingOptionNew context:nil];

    

    //观察缓存如今的进度，KVO进行观察，观察loadedTimeRanges

    [playerItem addObserver:self forKeyPath:@"loadedTimeRanges" options:NSKeyValueObservingOptionNew context:nil];

}



//观察是否播放

- (void)observeValueForKeyPath:(NSString *)keyPath ofObject:(id)object change:(NSDictionary *)change context:(void *)context{

    if ([keyPath isEqualToString:@"status"]) {

        if (playerItem.status == AVPlayerStatusReadyToPlay) {

            NSLog(@"開始播放");

            //须要開始获取数据，包含播放的总时长。播放的缓存，播放的当时时间

            [self loadData];

        }else{

            NSLog(@"播放失败");

        }

    }else{

        //kvo触发的另外一个属性

        NSArray *array = [playerItem loadedTimeRanges];

        //获取范围i

        CMTimeRange range = [array.firstObject CMTimeRangeValue];

        //从哪儿開始的

        CGFloat start = CMTimeGetSeconds(range.start);

        //缓存了多少

        CGFloat duration = CMTimeGetSeconds(range.duration);

        //一共缓存了多少

        CGFloat allCache = start+duration;

        NSLog(@"缓存了多少数据：%f",allCache);

        

        //设置缓存的百分比

        CMTime allTime = [playerItem duration];

        //转换

        CGFloat time = CMTimeGetSeconds(allTime);

        CGFloat y = allCache/time;

        NSLog(@"缓存百分比：--------%f",y);

        progressView.progress = y;

    }

}





#pragma mark -- 获取播放数据

- (void)loadData{

    

    __weak AVPlayerItem *xx = playerItem;

    __weak UISlider *cc = _slider;

    //第一个參数是每隔多长时间调用一次。在这里设置的是每隔1秒调用一次

    [player addPeriodicTimeObserverForInterval:CMTimeMake(1, 1) queue:NULL usingBlock:^(CMTime time) {

        //当前播放时间

        CGFloat current = xx.currentTime.value/xx.currentTime.timescale;

        

        //获取总时长

        CMTime time1 = xx.duration;

        float x = CMTimeGetSeconds(time1);

        NSLog(@"当前播放的秒数------- %f --------%f",current,x);

        

        //设置滑动条进度

        float v = current/x;

        

        //推断slider是否按下，按下去就先别赋值

        if (!isOpen) {

            cc.value = v;

        }

        

    }];



}



#pragma mark --- 创建UI

- (void)createUI{

    progressView = [[UIProgressView alloc]initWithProgressViewStyle:UIProgressViewStyleBar];

    progressView.frame = CGRectMake(0, 460, self.view.frame.size.width, 20);

    

    [self.view addSubview:progressView];

    

    _slider = [[UISlider alloc]initWithFrame:CGRectMake(0, 480, self.view.frame.size.width, 20)];

    [self.view addSubview:_slider];

    

    

    //加入点击事件

    [_slider addTarget:self action:@selector(sliderClick:) forControlEvents:UIControlEventTouchUpInside];

    //抬起来的事件

    [_slider addTarget:self action:@selector(sliderClickUp:) forControlEvents:UIControlEventTouchUpInside];

}



    //加入点击事件

- (void)sliderClick:(UISlider *)slider{

    NSLog(@"加入点击事件");

    isOpen = YES;

}



    //抬起来的事件

- (void)sliderClickUp:(UISlider *)slider{

    NSLog(@"抬起来的事件");

    isOpen = NO;

    

    //从这里開始播放

    CGFloat g = slider.value;

    //获取总时长

    CMTime time1 = playerItem.duration;

    float x = CMTimeGetSeconds(time1);

    //进行播放

    [player seekToTime:CMTimeMake(x * g,1)];

    //播放

    [player play];

    

}





@end