objective-c - 可达性问题

Question

当我单击按钮时，我在飞行模式下在 iPhone 上测试此代码显示一条消息，但是在我连接到互联网的状态下，播放按钮不起作用并且我的应用程序退出

这是代码：

-(void)playMovie {
    NSURL *url = [NSURL URLWithString:@"http://www.tvlaayoune.com/iphone/jt.mp4"];
    UIAlertView *errorView;
    if ([[Reachability sharedReachability]
            internetConnectionStatus] == NotReachable) {
        errorView = [[UIAlertView alloc]
                        initWithTitle: @"Unable To Connect To Server" 
                              message: @"Check your network connection and try again."
                             delegate: self
                        cancelButtonTitle: @"OK"
                        otherButtonTitles: nil];
    } else {
        moviePlayer = [[MPMoviePlayerController alloc]
                          initWithContentURL:url];
        [[NSNotificationCenter defaultCenter]
            addObserver:self
               selector:@selector(moviePlayBackDidFinish:)
                   name:MPMoviePlayerPlaybackDidFinishNotification
    object:moviePlayer];
        moviePlayer.controlStyle = MPMovieControlStyleDefault;
        moviePlayer.shouldAutoplay = YES;
        [self.view addSubview:moviePlayer.view];
        [moviePlayer setFullscreen:YES animated:YES];
    } [errorView show];
}

可能是什么问题？

Answer 1

如果我理解正确，当您有互联网并想要显示电影时，您的代码会崩溃。在这种情况下，最后一行代码将尝试显示errorView，但如果您有互联网，则不会分配。

在相同的 If 中移动该 show 调用：

-(void)playMovie {
    NSURL *url = [NSURL URLWithString:@"http://www.tvlaayoune.com/iphone/jt.mp4"];
    UIAlertView *errorView;
    if ([[Reachability sharedReachability]
            internetConnectionStatus] == NotReachable) {
        errorView = [[UIAlertView alloc]
                        initWithTitle: @"Unable To Connect To Server" 
                              message: @"Check your network connection and try again."
                             delegate: self
                        cancelButtonTitle: @"OK"
                        otherButtonTitles: nil];



         // Notice this line here:
         [errorView show];


     } else {
        moviePlayer = [[MPMoviePlayerController alloc]
                          initWithContentURL:url];
        [[NSNotificationCenter defaultCenter]
            addObserver:self
               selector:@selector(moviePlayBackDidFinish:)
                   name:MPMoviePlayerPlaybackDidFinishNotification
    object:moviePlayer];
        moviePlayer.controlStyle = MPMovieControlStyleDefault;
        moviePlayer.shouldAutoplay = YES;
        [self.view addSubview:moviePlayer.view];
        [moviePlayer setFullscreen:YES animated:YES];
    } 


    // Removed the show call from here

}