//引入系統文件#import <AVFoundation/AVFoundation.h>#import <AVKit/AVKit.h>@interface ViewController ()/** * 控制視頻播放的控件 */@property (weak, nonatomic) IBOutlet UISlider *progressSlider;/** * 聲明播放視頻的控件屬性[既可以播放視頻也可以播放音頻] */@property (nonatomic,strong)AVPlayer *player;/** * 播放的總時長 */@property (nonatomic,assign)CGFloat sumPlayOperation;  @end @implementation ViewController - (void)viewDidLoad { [super viewDidLoad]; // Do any additional setup after loading the view, typically from a nib. //設置播放的url NSString *playString = @"http://static.tripbe.com/videofiles/20121214/9533522808.f4v.mp4"; NSURL *url = [NSURL URLWithString:playString]; //設置播放的項目 AVPlayerItem *item = [[AVPlayerItem alloc] initWithURL:url]; //初始化player對象 self.player = [[AVPlayer alloc] initWithPlayerItem:item]; //設置播放頁面 AVPlayerLayer *layer = [AVPlayerLayer playerLayerWithPlayer:_player]; //設置播放頁面的大小 layer.frame = CGRectMake(0, 0, [UIScreen mainScreen].bounds.size.width, 300); layer.backgroundColor = [UIColor cyanColor].CGColor; //設置播放窗口和當前視圖之間的比例顯示內容 layer.videoGravity = AVLayerVideoGravityResizeAspect; //添加播放視圖到self.view [self.view.layer addSublayer:layer]; //設置播放進度的默認值 self.progressSlider.value = 0; //設置播放的默認音量值 self.player.volume = 1.0f;  }#pragma mark - 開始按鈕響應方法- (IBAction)startPlayer:(id)sender { [self.player play];}#pragma mark - 暫停按鈕響應方法- (IBAction)stopPlayer:(id)sender { [self.player pause];}#pragma mark - 改變進度- (IBAction)changeProgress:(id)sender { self.sumPlayOperation = self.player.currentItem.duration.value/self.player.currentItem.duration.timescale; //CMTimeMake(a,b) a表示當前時間，b表示每秒鐘有多少幀 [self.player seekToTime:CMTimeMakeWithSeconds(self.progressSlider.value*self.sumPlayOperation, self.player.currentItem.duration.timescale) completionHandler:^(BOOL finished) {  [self.player play]; }];  }