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];