java - AudioTrack - IllegalStateException : play() called on uninitialized AudioTrack

Question

我有一个带有 AudioTrack 的线程，我在向下按钮上调用它，在向上按钮上我想停止音频。到目前为止，一切都很好。我的应用程序有 Activity A 和 Activity B。 Activity A 是一些菜单，我从其中启动 Activity B，这是主 Activity ，我将其称为 AudioTrack 等等。问题是，一切都工作正常，直到我第三次进入 Activity B，然后当我打电话玩时发生了这种情况。

E/AudioTrack: AudioFlinger could not create track, status: -12
E/AudioTrack-JNI: Error -12 initializing AudioTrack
E/android.media.AudioTrack: Error code -20 when initializing AudioTrack.
java.lang.IllegalStateException: play() called on uninitialized AudioTrack.

第一次和第二次我什至不需要调用play，只需进入Activity B，但是当我想第三次调用play时，发生了这个错误。为什么？？？

Activity B 看起来像这样

Activity B playTune(){
    if(tuneThread == null){
        tuneThread = new startSI();
        //    tuneThread.setTuneFreq(tuneFreq);
        tuneThread.start();
    }
    return this;
}

void setTuneFreq(double tuneFreq) {
    this.tuneFreq = tuneFreq;
    if(tuneThread != null){
        tuneThread.setTuneFreq(tuneFreq);
    }
}

void stopTune(){
    if(tuneThread != null){
        tuneThread.stopTune();
        tuneThread = null;
    }
}

protected void onPause() {
    stopTune();
    super.onPause();
}

protected void onStop() {
    stopTune();
    super.onStop();

这就是我调用和/或停止线程的方式

setTuneFreq(double);

我调用 OnSenzorChanged(事件监听器)，因为我需要基于陀螺仪数据的频率。

playTune();

我在按下按钮后ACTION_DOWN后调用OnTouchListener，只要按下按钮，AudioTrack就会生成信号(直到ACTION_UP)，然后我调用

stopTune();

AudioTrack 线程看起来像这样

public class startSI extends Thread {

    private boolean isRunning;
    private double tuneFreqSI;


    private int sr = 44100;
    private int sibuffsize = AudioTrack.getMinBufferSize(sr,
            AudioFormat.CHANNEL_OUT_MONO, AudioFormat.ENCODING_PCM_16BIT);
    private AudioTrack siaudioTrack = new AudioTrack(AudioManager.STREAM_MUSIC,
            sr, AudioFormat.CHANNEL_OUT_MONO,
            AudioFormat.ENCODING_PCM_16BIT, sibuffsize,
            AudioTrack.MODE_STREAM);


    @Override
    public void run() {

        super.run();
        isRunning = true;


        short samples[] = new short[sibuffsize];
        int amp = 32767;
        double twopi = 8. * Math.atan(1.);
        double ph = 0.0;

        try {

        siaudioTrack.play();

        } catch(IllegalStateException e) {
            System.out.println("error play "+e);   
        }

        while (isRunning) {

            double fr = tuneFreqSI;
            double fLFO = frLFO;
            for (int i = 0; i < sibuffsize; i++) {
                samples[i] = (short) (amp * Math.sin(ph));
                ph += twopi * fr / sr;               
            }
            siaudioTrack.write(samples, 0, sibuffsize);       

        }
        try {
        siaudioTrack.stop();
        siaudioTrack.release();

        }catch(IllegalStateException e) {
            System.out.println("error stop "+e);
        }

    }

    public void setTuneFreq(double tuneFreq, double frLFO, double ampLFO) {

        this.tuneFreqSI = tuneFreq;
        this.frLFO = frLFO;
        this.ampLFO = ampLFO;
    }


    public void stopTune() {
        isRunning = false;

        try {
            this.join();
            this.interrupt();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

即使在第三次打开 Activity B 后，我也需要启动该线程。

我做错了什么？

Answer 1

我认为您的音轨同时被垃圾收集器销毁了。因此，我建议您在 run() 方法开始时使用此行重新初始化 siaudioTrack。

this.siaudioTrack = new AudioTrack(AudioManager.STREAM_MUSIC, sr, AudioFormat.CHANNEL_OUT_MONO, AudioFormat.ENCODING_PCM_16BIT, sibuffsize, AudioTrack.MODE_STREAM);