AVAudioPlayer 不同时播放声音

Question

我正在尝试同时为 AVAudioPlayer 播放几个声音文件。我读了一个线程来解释如何做到这一点@AVAudioPlayer Help: Playing multiple sounds simultaneously, stopping them all at once, and working around Automatic Reference Counting。这似乎是一个奇怪的问题，因为当我尝试一次只播放一个文件时（当 self.options.on 为 ON 时），它可以工作，但是当我尝试创建多个实例（else 语句）并且什么都不播放时戏剧。我检查了输出文件的 URL 是否正确，那么它不起作用的原因是什么？

谢谢！

- (void)playTapped:(id)sender 
{
    if (!recorder.recording)
    {
        if(self.options.on)
        {
            AVAudioSession *session = [AVAudioSession sharedInstance];
            [session setCategory:AVAudioSessionCategoryPlayback error:nil];

            NSArray *pathComponents = [NSArray arrayWithObjects:
                                       [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject],
                                       [NSString stringWithFormat:@"sound%i.m4a",last],
                                       nil];
            NSURL *outputFileURL = [NSURL fileURLWithPathComponents:pathComponents];

            player = [[AVAudioPlayer alloc] initWithContentsOfURL:outputFileURL error:nil];
            NSLog(@"%@",player.url);
            [player setDelegate:self];
            [player play];
        }
        else
        {
            // trying to play all sounds at once
            for (NSString *str in self.soundsCreated){
                NSLog(@"%@",str);
                NSArray *pathComponents = [NSArray arrayWithObjects:
                                           [NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES) lastObject],
                                           [NSString stringWithFormat:@"sound%@.m4a",str],
                                           nil];
                NSURL *outputFileURL = [NSURL fileURLWithPathComponents:pathComponents];

                AVAudioPlayer *audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:outputFileURL error:nil];
                NSLog(@"%@",audioPlayer.url);
                [audioPlayer prepareToPlay];
                [audioPlayer setDelegate:self];
                [audioPlayer play];

            }
        } 
    }
}

注意 我尝试使用NSError check 进行初始化，但没有收到任何错误：

NSError *sessionError = nil;
AVAudioPlayer *audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:outputFileURL error:&sessionError];
if (sessionError)
{
    NSLog(@"Error in audioPlayer: %@",[sessionError localizedDescription]);
}

解决方案 我的NSMutableArrays 的初始化似乎有问题。

我将它们更改为：

self.soundsCreated = [[NSMutableArray alloc]init];
self.playerArray = [[NSMutableArray alloc]init];

到

self.soundsCreated = [NSMutableArray new];
self.playerArray = [NSMutableArray new];

然后解决了它

Answer 1

我在播放小文件时也遇到过同样的情况：

这是我的解决方案（示例）

- (void)dropSoundWhileRefresh
{
    NSError *sessionError = nil;
    [[AVAudioSession sharedInstance] setCategory:AVAudioSessionCategoryAmbient error:&sessionError];
    [[AVAudioSession sharedInstance] setActive:YES error:&sessionError];
    [[AVAudioSession sharedInstance] setDelegate:self];
    NSURL *musicFile = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"waterDrops" ofType:@"mp3"]];
    dropSound = [[AVAudioPlayer alloc] initWithContentsOfURL:musicFile error:nil];
    [dropSound setDelegate:self];
    [dropSound setVolume:0.10];
    [dropSound setNumberOfLoops:0];
    [dropSound play];
}

Answer 2

不要将错误传递为 nil 试试这个并检查初始化是否正确。

AVAudioPlayer *audioPlayer = [[AVAudioPlayer alloc] initWithContentsOfURL:url error:&error];
if (error) 
{
   DebugLog(@"Error in audioPlayer: %@",[error localizedDescription]);
}