xcode – UIScrollView在添加新子视图时中断

我很擅长编写iOS平台和目标C.我正在编写一个简单的iPhone应用程序,利用故事板,通过嵌入在UIScrollView中的UI ImageView显示一个高png文件,旁边的按钮将播放电影.

我的问题是,当电影完成/退出并返回到原始屏幕时,UIScrollView中的滚动不起作用.我已经确定了“原因”.当我将MPMoviePlayerViewController object.view添加到self.view子视图时,会发生这种情况.但我不确定如何纠正这个问题.这是我的提炼代码：

.h文件

@interface StuffViewController : UIViewController 

@property (strong,nonatomic) IBOutlet UIImageView *imageView;
@property (strong,nonatomic) IBOutlet UIScrollView *scrollView;

-(IBAction) playMovie;
-(void) moviePlayBackDidFinish:(NSNotification*)notification;

@end

.m文件

-(void) viewDidLoad {
    self.imageView.image = [UIImage imageNamed:@"image.png"];
}

-(void) viewDidAppear:(BOOL)animated {
    self.scrollView.contentSize = self.imageView.image.size;
}

-(void) playMovie {
    NSURL *movieURL = [NSURL fileURLWithPath:[[NSBundle mainBundle]
                                         pathForResource:@"movieTitle" ofType:@"mp4"]];
    MPMoviePlayerController *moviePlayer = [[MPMoviePlayerController alloc] 
                                                initWithContentURL:movieURL];
       [[NSNotificationCenter defaultCenter] addObserver:self
                                        selector:@selector(moviePlayBackDidFinish:)
                                            name:MPMoviePlayerPlaybackDidFinishNotification
                                          object:moviePlayer];
    [moviePlayer setMovieSourceType:MPMovieSourceTypeFile];
    [[self view] addSubview:moviePlayer.view];   //SCROLLING BREAKS HERE
    [moviePlayer setFullscreen:YES];
    [moviePlayer play];
}

-(void)moviePlayBackDidFinish: (NSNotification*)notification {
    MPMoviePlayerController *movieDone = [notification object];
    [[NSNotificationCenter defaultCenter] removeObserver:self];
    [movieDone.view removeFromSuperview];
    [movieDone setFullscreen:NO];
}

我已经通过评论部分确定了罪魁祸首,就像我说的那样,滚动“锁定”在“[[self view] addSubview：moviePlayer.view];”直到我导航到另一个视图然后回来之前,并没有恢复.

对此的任何和所有帮助将不胜感激.

编辑：我发现了一个有趣的皱纹,可能有助于发现潜在的问题.

我一直在使用MPMoviePlayerController.但是,在切换到MPMoviePlayerViewController时,一些有趣的事情一直在发生.

这是改变了 – (void)playMovie

-(void) playMovie {
   self.scrollView.contentOffset = CGPointZero;
   NSURL *url = [NSURL fileURLWithPath:[[NSBundle mainBundle]
                                    pathForResource:totalTitle ofType:@"mp4"]];
   MPMoviePlayerViewController *playerController =  [[MPMoviePlayerViewController alloc] initWithContentURL:url];
   [self presentMoviePlayerViewControllerAnimated:playerController];
   playerController.moviePlayer.movieSourceType = MPMovieSourceTypeFile;
   [playerController.moviePlayer play];
   playerController = nil;
}

有趣的是,UIScrollView仍然可以正常工作,如果它完全向下滚动它将无法再从电影开始时的位置向上滚动.我通过在playMovie的开头添加self.scrollView.contentOffset = CGPointZero来修复此问题,以告诉scrollView移动到顶部(因此上面没有任何内容可以滚动回去).我假设在viewDidAppear中的代码中添加某种if语句会使scrollView.contentSize不能重新执行,这可能会解决无法向上滚动的问题,但是我喜欢它的“清洁度”顶端.

最后一个问题.像这样使用MPMoviePlayerViewController在MPMoviePlayerViewController * playerController = [[MPMoviePlayerViewController alloc] initWithContentURL：url]时,会在我的调试器中弹出一些有趣的错误.行已执行.它们如下：

Oct 25 10:25:51 Compy.local AppName[14590] <Error>: CGContextSaveGState: invalid context 0x0 
Oct 25 10:25:51 Compy.local AppName[14590] <Error>: CGContextClipToRect: invalid context 0x0
Oct 25 10:25:51 Compy.local AppName[14590] <Error>: CGContextTranslateCTM: invalid context 0x0
Oct 25 10:25:51 Compy.local AppName[14590] <Error>: CGContextDrawShading: invalid context 0x0
Oct 25 10:25:51 Compy.local AppName[14590] <Error>: CGContextRestoreGState: invalid context 0x0

它似乎没有破坏任何东西.然而,当谈到错误的错误陈述时,我倾向于成为完美主义者.我已经对这些错误进行过一些研究,但是我没有找到任何合适的东西可以在这种情况下发挥作用.

感谢目前为止所有的帮助！我再一次感谢任何和所有帮助.

MPMoviePlayerController *movieDone = [notification object];

MPMoviePlayerController *movieDone = (MPMoviewPlayerController *)[notification object];

movieDone = nil;