Question

我有一系列音频文件，我想按顺序播放。我设置了audioPlayerDidFinishPlaying委托方法来启动序列中的下一个文件。如果我关闭屏幕锁定或者我在模拟器或iOS4设备上运行它，这没有问题。但是，当我在断开连接的设备上运行它时，iOS5，屏幕锁定，它在第一首曲目后停止。屏幕锁定开启后，有没有办法启动新的音轨？

这是我的基本代码

// Registers this class as the delegate of the audio session.
[[AVAudioSession sharedInstance] setDelegate: self];

// Use this code instead to allow the app sound to continue to play when the screen is locked.
[[AVAudioSession sharedInstance] setCategory: AVAudioSessionCategoryPlayback error: nil];

UInt32 doSetProperty = 0;
AudioSessionSetProperty ( kAudioSessionProperty_OverrideCategoryMixWithOthers,
                         sizeof (doSetProperty),
                         &doSetProperty
                         );

// Registers the audio route change listener callback function
AudioSessionAddPropertyListener (
                                 kAudioSessionProperty_AudioRouteChange,
                                 audioRouteChangeListenerCallback,
                                 self
                                 );

// Activates the audio session.

NSError *activationError = nil;
[[AVAudioSession sharedInstance] setActive: YES error: &activationError];

    NSString *path = [[NSBundle mainBundle] pathForResource:filename ofType:@"m4a"];  
    float vol = [appSoundPlayer volume];

    AVAudioPlayer * newAudio=[[AVAudioPlayer alloc] initWithContentsOfURL:[NSURL fileURLWithPath:path] error:NULL];  
    self.appSoundPlayer = newAudio; // automatically retain audio and dealloc old file if new file is loaded

    [newAudio release]; // release the audio safely

    appSoundPlayer.delegate = self; 
    [appSoundPlayer prepareToPlay];
    [appSoundPlayer setNumberOfLoops:0];
    [appSoundPlayer play];
    [appSoundPlayer setVolume:vol];
    [progTime setProgress:0];
}


   - (void) audioPlayerDidFinishPlaying: (AVAudioPlayer *) lappSoundPlayer successfully: (BOOL) flag {
    //... code here to select nex sound track
                    [lappSoundPlayer play];
    }

我已经做到了，所以即使屏幕锁定开启，应用程序仍继续播放当前曲目，我无法让它启动下一曲目。

注意：我已经确认这适用于iOS4。

Answer 1

您是否设置了音频会话类别，具体为AVAudioSessionCategoryPlayback，如here所述？

[[AVAudioSession sharedInstance] setDelegate: self];    
NSError *error = nil;
[[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryPlayback error:&error];

如果这不起作用，根据Apple开发论坛this message中的用户ascanio，尝试另一件事就是将你的应用设置为监听远程控制事件：

[[UIApplication sharedApplication] beginReceivingRemoteControlEvents];

iphone iOS5 audioPlayerDidFinishPlaying不叫屏幕锁？

1 个答案: