Media Player基於iOS4和部署iOS3的問題

Question

當運行在設備3.1.2，爲什麼它也通過if（NSClassFromString（@「MPMoviePlayerViewController」）！= nil） 並做iOS4的代碼，然後它會崩潰，如何解決這個問題？

   if(NSClassFromString(@"MPMoviePlayerViewController") != nil) { 
        // iOS 4 code 
        NSLog(@"MPMoviePlayerViewController"); 
        MPMoviePlayerViewController *mp = [[MPMoviePlayerViewController alloc] initWithContentURL:[NSURL URLWithString:AppDelegate.PushLink]]; 
        if (mp) { 
         // save the movie player object 
         self.theMovie4 = mp; 
         [mp release]; 
         //Present      
         [self presentMoviePlayerViewControllerAnimated:self.theMovie4]; 

         // Play the movie! 
         self.theMovie4.moviePlayer.movieSourceType = MPMovieSourceTypeStreaming; 
         [self.theMovie4.moviePlayer play]; 
        } 
       } 
       else { 
        //iOS 3 Code 
        AppDelegate = nil; 
        AppDelegate = [[UIApplication sharedApplication] delegate]; 
        [AppDelegate ForceHideNavigationBar]; 
        theMovie3 = nil; 

        [[NSNotificationCenter defaultCenter] addObserver:self 
                  selector:@selector(moviePreloadDidFinish:) 
                   name:MPMoviePlayerContentPreloadDidFinishNotification 
                   object:theMovie3]; 

        [[NSNotificationCenter defaultCenter] addObserver:self 
                  selector:@selector(moviePlayBackDidFinish:) 
                   name:MPMoviePlayerPlaybackDidFinishNotification 
                   object:theMovie3]; 

        // Register to receive a notification when the movie scaling mode has changed. 
        [[NSNotificationCenter defaultCenter] addObserver:self 
                  selector:@selector(movieScalingModeDidChange:) 
                   name:MPMoviePlayerScalingModeDidChangeNotification 
                   object:theMovie3]; 

        theMovie3 = [[MPMoviePlayerController alloc] initWithContentURL: [NSURL URLWithString:AppDelegate.PushLink]]; 

        [theMovie3 play]; 

       } 

Answer 1

我正在做一個非常類似的事情，我的應用程序使用4.0作爲基礎SDK，但我也瞄準iOS3設備。我必須檢查操作系統版本以正確提供視頻播放的正確代碼。例如：

- (void) playMovieAtURL: (NSURL*) theURL { 
    NSLog(@"playMovieAtURL"); 

if ([[[UIDevice currentDevice] systemVersion] doubleValue] >= 3.2) { 
      NSLog(@"> 3.2"); 
      MPMoviePlayerViewController *mp = [[MPMoviePlayerViewController alloc] initWithContentURL:theURL]; 

      if (mp) 
      { 
       // save the movie player object 
       //self.moviePlayerViewController = mp; 
       //[mp release]; 
       [self presentMoviePlayerViewControllerAnimated:mp]; 
       mp.moviePlayer.movieSourceType = MPMovieSourceTypeFile; 
       [mp.moviePlayer play]; 
       [mp release]; 
      } 

     } 
    else if ([[[UIDevice currentDevice] systemVersion] doubleValue] < 3.2) { 
      NSLog(@"< 3.2"); 

      MPMoviePlayerController* theMovie = [[MPMoviePlayerController alloc] initWithContentURL: theURL]; 

      theMovie.scalingMode = MPMovieScalingModeAspectFill; 

      // Register for the playback finished notification 
      [[NSNotificationCenter defaultCenter] 
      addObserver: self 
      selector: @selector(myMovieFinishedCallback:) 
      name: MPMoviePlayerPlaybackDidFinishNotification 
      object: theMovie]; 

      // Movie playback is asynchronous, so this method returns immediately. 
      [theMovie play]; 



     } 

    } 

希望這有助於！

Answer 2

[[NSNotificationCenter defaultCenter] addObserver:self selector:@selector(moviePlayBackDidFinish:) 
     name:MPMoviePlayerPlaybackDidFinishNotification object:nil]; 

    NSString *movpath = [[NSBundle mainBundle] pathForResource:@"splash" ofType:@"mp4"]; 
    MPMoviePlayerViewController* mpviewController = [[MPMoviePlayerViewController alloc] 
         initWithContentURL:[NSURL fileURLWithPath:movpath]]; 
    [window addSubview:mpviewController.view]; 
     [window makeKeyAndVisible]; 
    MPMoviePlayerController *mp = [mpviewController moviePlayer]; 
    [mp prepareToPlay]; 
    [[mpviewController moviePlayer] play]; 

此代碼將在iOS4的

工作，這一次的電影完成了，因爲你必須創建通知的方法，但不退出。此外，您還需要在那裏發佈影片，以便您可以捕獲內存泄漏。