Xcode 4.2 "_OBJC_CLASS_$_MPMoviePlayerViewController 编译不通过

#import "ViewController.h"




@implementation ViewController




-(void)moviePlayerDidFinish:(NSNotification *) aNote{


MPMoviePlayerController*player=[aNote object];
[[NSNotificationCenterdefaultCenter] removeObserver:self
                                               name:MPMoviePlayerPlaybackDidFinishNotification
                                               object:player];
    [player stop];

//[self dismissMoviePlayerViewControllerAnimated];
//[playerViewController release];









}


-(void)buttonClicked:(id)sender{

NSString*filePath=[[[NSBundlemainBundle] resourcePath] stringByAppendingPathComponent:@"b.mov"];
   NSURL *movieURL=[NSURL fileURLWithPath:filePath];

playerViewController=[[MPMoviePlayerViewControlleralloc]initWithContentURL:movieURL];
[[NSNotificationCenterdefaultCenter] addObserver:self
                                            selector:@selector(moviePlayerDidFinish:)
                                                name:MPMoviePlayerPlaybackDidFinishNotification
                                              object:nil];

[selfpresentMoviePlayerViewControllerAnimated:playerViewController];    



     }


老是报错呀，编译就不通过，怎么办？


MediaPlayer.framework 已经引入了，就是编译不通过。想了一个下午了


ld: warning: ignoring file /Users/user/自己的程序/MoviePlayer/MediaPlayer.framework/MediaPlayer, file was built for unsupported file format which is not the architecture being linked (i386)
Undefined symbols for architecture i386:
  "_OBJC_CLASS_$_MPMoviePlayerViewController", referenced from:
      objc-class-ref in ViewController.o
  "_MPMoviePlayerPlaybackDidFinishNotification", referenced from:
      -[ViewController moviePlayerDidFinish:] in ViewController.o
      -[ViewController buttonClicked:] in ViewController.o
ld: symbol(s) not found for architecture i386
clang: error: linker command failed with exit code 1 (use -v to see invocation)


错误信息好像是找不到MPMoviePlayerPlaybackDidFinishNotification一样的，可是我的framework真的引入了，好像framework的引入菜单变了，还是我引入的方法不对？