Question

我正在使用 iOS5 。

我正在开发HTTPLivestream项目。我正在使用 MPMovieplayer ，我的问题是当应用程序进入后台时没有音频。我在后台模式中更改plist是audio.But没有结果请帮帮我。

AppDel

- (void)applicationDidEnterBackground:(UIApplication *)application {
  [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:nil];
  [[AVAudioSession sharedInstance] setActive: YES error: nil];

  UIApplication *app = [UIApplication sharedApplication];
  backgroundTask = [app beginBackgroundTaskWithExpirationHandler:^{
  }];

  dispatch_async(dispatch_get_global_queue(DISPATCH_QUEUE_PRIORITY_HIGH, 0), ^{
  });
}

RadioControlView

  NSString *path =[[NSString alloc] initWithString:@"http://*******/alayam/alayam/playlist.m3u8"];

  audioUrl=[NSURL URLWithString:path];

  appDelegate.player =  [[MPMoviePlayerController alloc] initWithContentURL:audioUrl];
                                   [[NSNotificationCenter defaultCenter] addObserver:self 
                                                         selector:@selector(loadStateDidChange:) 
                                                             name:MPMoviePlayerLoadStateDidChangeNotification 
                                                           object:appDelegate.player];
                if ([appDelegate.player respondsToSelector:@selector(loadState)]) 
                {
                    [appDelegate.player setControlStyle:MPMovieControlModeVolumeOnly];
                    [appDelegate.player setFullscreen:YES];
                    [appDelegate.player prepareToPlay];
                 }

- (void)loadStateDidChange:(NSNotification *)notification
      {   
        [[NSNotificationCenter defaultCenter]removeObserver:self name:MPMoviePlayerLoadStateDidChangeNotification object:appDelegate.player];

      }

先谢谢

Answer 1

您需要结合ios5中的背景支持设置 -

进行遥控设置

//注册您的应用程序以进行远程控制

if([[UIApplication sharedApplication]  respondsToSelector:@selector(beginReceivingRemoteControlEvents)])
    [[UIApplication sharedApplication] beginReceivingRemoteControlEvents];


// allows you to play in the background when app is suspended in iOS5
[[AVAudioSession sharedInstance] setDelegate: self];
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayback error:nil];

将这两个设置放在应用程序didFinishLaunching delegate

中

Answer 2

尝试在初始化播放器之前激活音频会话，例如在app启动委托中：

- (void)applicationDidFinishLaunching:(UIApplication *)application NSError *error = nil; [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:&error]; [[AVAudioSession sharedInstance] setActive:YES error:&error]; // other init stuff ... }

PS：您需要在设备上才能使音频会话正常工作，模拟器不会削减它。

Answer 3

如果您在模拟器上进行测试，那么它不能在模拟器上运行，请使用设备。如果您正在使用设备而音频不在后台播放，那么您可以将您的完整源代码发送给我khalid0491@gmail.com。我也在我的应用程序中完成了。我的代码如下。

- (void)viewDidLoad 
{
    [super viewDidLoad];

    NSError *setCategoryErr = nil;
    NSError *activationErr  = nil;
    [[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayback error: &setCategoryErr];
    [[AVAudioSession sharedInstance] setActive: YES error: &activationErr];
}

并在plist中我创建了一个名为＆＃34的数组;所需的背景模式＆＃34;并在数组名称中插入一个项目＆＃34; App Plays Audio＆＃34;。

MPMoviePlayer在应用程序进入后台时播放

AppDel

RadioControlView

3 个答案: