Question

我在AFNetworking的帮助下从服务器下载音频文件。该文件已成功下载，因为我可以通过进度块查看它。我将它存储在Documents目录中，但后来我无法播放它。这是我的代码： -

-(void)downloadAudioFileFromUrl:(NSString *)str_url{

    [SVProgressHUD show];
    NSURLRequest *request = [NSURLRequest requestWithURL:[NSURL URLWithString:str_url]];
    AFHTTPRequestOperation *operation = [[AFHTTPRequestOperation alloc] initWithRequest:request];

    NSArray *paths = NSSearchPathForDirectoriesInDomains(NSDocumentDirectory, NSUserDomainMask, YES);
    NSString *path = [[paths objectAtIndex:0] stringByAppendingPathComponent:@"momentsAudioToast.mp3"];
    operation.outputStream = [NSOutputStream outputStreamToFileAtPath:path append:NO];

    [operation setCompletionBlockWithSuccess:^(AFHTTPRequestOperation *operation, id responseObject) {
        NSLog(@"Successfully downloaded file to %@", path);
        [SVProgressHUD dismiss];

        if ([[NSFileManager defaultManager] fileExistsAtPath:path]) {


            [self playSound:path];
        }



    } failure:^(AFHTTPRequestOperation *operation, NSError *error) {
        NSLog(@"Error: %@", error);
        [SVProgressHUD dismiss];
    }];

    [operation setDownloadProgressBlock:^(NSUInteger bytesWritten, long long totalBytesWritten, long long totalBytesExpectedToWrite) {

        //[progressView setProgress: totalBytesWritten*1.0f / totalBytesExpectedToWrite animated: YES];
        NSLog(@"downloaded %lld of %lld bytes and progress is %f", totalBytesWritten, totalBytesExpectedToWrite, totalBytesWritten*1.0f /  totalBytesExpectedToWrite);
        if(totalBytesWritten >= totalBytesExpectedToWrite)
        {
            //progressView.hidden = YES;
        }
    }];


    [operation start];


}

- (void)playSound:(NSString *)path {
    [self.player prepareToPlay];
    //UIButton *audioButton = (UIButton *)sender;
    //[audioButton setImage:[UIImage imageNamed:@"sound_preview.png"] forState:UIControlStateNormal];
    NSData *audioData = [NSData dataWithContentsOfFile:path options: 0 error:nil];

    self.player = [[AVAudioPlayer alloc] initWithData:audioData error:nil];
    double duration = [self.player duration];

    NSLog(@"%f", duration);
    NSError * error;

    self.player.delegate = self;
    self.player.numberOfLoops = 0;
    if (error) {
        NSLog(@"Error: %@",[error description]);
    }
    else {
        self.player.delegate = self;
        [self.player play];
    }
}

如果我做错了，请帮忙。

提前致谢。

Answer 1

首先，确保您对AVAudioPlayer实例player保持强烈的引用，如下所示：

@property (nonatomic, strong) AVAudioPlayer *player;

第二，最有可能，这将是与路径相关的问题。尝试在播放时重建路径。

第三，，仔细检查文件是否存在，以及在任何音频播放器中播放时播放的文件。

Answer 2

在您的情况下，如果您声明音频播放器完美。

并设置代表＆amp;如果从Web服务的音频文件中获取NSData。

然后您需要再插入一行代码并再次检查。

[self.player setVolume: 1.0];

下载音频，无法使用AVAudioPlayer播放

2 个答案: