MediaPlayer 的影片是放在 UIView 里面，而 AVPlayer 是放在 AVPlayerLayer 里面，AVPlayerLayer 是 CALayer 的子类别。
使用 MediaPlayer 前，要记得加入MediaPlayer.framework及#import <MediaPlayer/MediaPlayer.h>
使用 AVPlayer 前，要记得加入AVFoundation.framework及#import <AVFoundation/AVFoundation.h>
使用MediaPlayer來播放影片
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"backspace" ofType:@"mov"];
NSURL *sourceMovieURL = [NSURL fileURLWithPath:filePath];
moviePlayer = [[MPMoviePlayerController alloc] initWithContentURL:sourceMovieURL];
moviePlayer.view.frame=CGRectMake(0, 0, 1024, 768);
moviePlayer.controlStyle=MPMovieControlStyleNone;
// Play the movie!
[self.view addSubview:moviePlayer.view];
使用AVPlayer來播放影片
NSString *filePath = [[NSBundle mainBundle] pathForResource:@"backspace" ofType:@"mov"];
NSURL *sourceMovieURL = [NSURL fileURLWithPath:filePath];
AVAsset *movieAsset = [AVURLAsset URLAssetWithURL:sourceMovieURL options:nil];
AVPlayerItem *playerItem = [AVPlayerItem playerItemWithAsset:movieAsset];
AVPlayer *player = [AVPlayer playerWithPlayerItem:playerItem];
AVPlayerLayer *playerLayer = [AVPlayerLayer playerLayerWithPlayer:player];
playerLayer.frame = self.view.layer.bounds;
playerLayer.videoGravity = AVLayerVideoGravityResizeAspect;
[self.view.layer addSublayer:playerLayer];
[player play];
