转换错误OBJ-C到Swift 3

Question

我正在尝试将EZAudio（https://github.com/syedhali/EZAudio）Objective-C库转换为Swift 3.我正在进行＆＃34; EZAudioPlayFileExample＆＃34;参与其中。

的Objective-C

- (void)openFileWithFilePathURL:(NSURL*)filePathURL
{
    self.audioFile = [EZAudioFile audioFileWithURL:filePathURL];
    self.filePathLabel.text = filePathURL.lastPathComponent;

    //
    // Plot the whole waveform
    //
    self.audioPlot.plotType = EZPlotTypeBuffer;
    self.audioPlot.shouldFill = YES;
    self.audioPlot.shouldMirror = YES;

    //
    // Get the audio data from the audio file
    //
    __weak typeof (self) weakSelf = self;
    [self.audioFile getWaveformDataWithCompletionBlock:^(float **waveformData,
                                                         int length)
    {
        [weakSelf.audioPlot updateBuffer:waveformData[0]
                          withBufferSize:length];
    }];
}

Swift 3

func openFileWithFilePathURL(filePathURL: NSURL) {
        self.audioFile = EZAudioFile(url: filePathURL as URL!)

        //
        // Plot the whole waveform
        //
        self.plot.plotType = .buffer
        self.plot.shouldFill = true
        self.plot.shouldMirror = true

        //
        // Get the audio data from the audio file
        //
        weak var weakSelf = self
        self.audioFile.getWaveformData(completionBlock: {(_ waveformData: Float, _ length: Int) -> Void in
            weakSelf?.plot.updateBuffer(waveformData[0], withBufferSize: length) // error in this line as Float as no subscript members
        })
    }

我知道Float参数没有像[0]那样的下标成员。但我想转换Objective-C代码。或者这里有人使用这个库的Swift版本。注意：我想要＆＃34; EZAudioPlayFileExample＆＃34;在它。

Answer 1

float **waveformData实际上是unsafemutablepointer。所以你必须在swift 3.0中使用unsafemutablepointer。 您可以在swift中使用unsafemutablepointer，如

UnsafeMutablePointer<UnsafeMutablePointer<Float>>

您可以使用

self.audioFile.getWaveformData(completionBlock: {(_ waveformData: UnsafeMutablePointer<UnsafeMutablePointer<Float>>, _ length: Int) -> Void in
            weakSelf?.plot.updateBuffer(waveformData[0], withBufferSize: length)  
        })

我刚刚下载了旧版本的EZAudio swift实现并转换为swift 3.0。它可以在link上找到 我不知道这会对你有什么帮助，但你可以在此基础上建立。 您还可以参考gitHub页面上报告的此issue