Question

所以我有一个按钮可以在按下时播放录音带，然后在第二次按下时停止录音带。当我单击按钮时，它退出应用程序。我不知道为什么。请帮忙！

public void Playbutton(View view) {

            File file = new File(Environment.getExternalStorageDirectory(), "test.pcm");

            int shortSizeInBytes = Short.SIZE / Byte.SIZE;

            int bufferSizeInBytes = (int) (file.length() / shortSizeInBytes);
            short[] audioData = new short[bufferSizeInBytes];

            try {
                InputStream inputStream = new FileInputStream(file);
                BufferedInputStream bufferedInputStream = new BufferedInputStream(inputStream);
                DataInputStream dataInputStream = new DataInputStream(bufferedInputStream);

                int i = 0;
                while (dataInputStream.available() > 0) {
                    audioData[i] = dataInputStream.readShort();
                    i++;
                }

                dataInputStream.close();

                AudioTrack audioTrack = new AudioTrack(
                        AudioManager.STREAM_MUSIC,
                        11025,
                        AudioFormat.CHANNEL_IN_MONO,
                        AudioFormat.ENCODING_PCM_16BIT,
                        bufferSizeInBytes,
                        AudioTrack.MODE_STREAM);

                if (playbuttonstatus){
                playBtn.setText(getString(R.string.stop));
                audioTrack.play();
                audioTrack.write(audioData, 0, bufferSizeInBytes);
                    playbuttonstatus = false;}
                else{
                    playBtn.setText(getString(R.string.play));
                    playbuttonstatus = true;
                    audioTrack.pause();
                    audioTrack.flush();}
            } catch (FileNotFoundException e){
                e.printStackTrace();
            } catch (IOException e) {
                e.printStackTrace();
            }

Answer 1

在项目中使用此代码。我认为它会对你有所帮助：

    Boolean audiopaused=true;

    Button play.setOnclickListener(new Onclicklistener){
    if (audiopaused){
        audio.start();
        }esle{
        audio.stop();
    }
    }

Answer 2

现在，无论playbuttonstatus的状态如何，您始终都会运行相同的初始化。因此，在您首次在AudioTrack的一个实例上开始播放并再次按下该按钮之后，您再创建另一个新AudioTrack实例，并尝试停止它，尽管它还没有播放。这可能会导致IllegalStateException。（而且你也没能阻止原来的。）

您可以将audioTrack作为playButton()方法之外的类的成员变量：

private AudioTrack audioTrack;

然后您可以更改代码，以便启动和停止相同的AudioTrack。

public void playButton(View view) {

    if (playbuttonstatus){
        File file = new File(Environment.getExternalStorageDirectory(), "test.pcm");

        int shortSizeInBytes = Short.SIZE / Byte.SIZE;

        int bufferSizeInBytes = (int) (file.length() / shortSizeInBytes);
        short[] audioData = new short[bufferSizeInBytes];

        try {
            InputStream inputStream = new FileInputStream(file);
            BufferedInputStream bufferedInputStream = new BufferedInputStream(inputStream);
            DataInputStream dataInputStream = new DataInputStream(bufferedInputStream);

            int i = 0;
            while (dataInputStream.available() > 0) {
                audioData[i] = dataInputStream.readShort();
                i++;
            }

            dataInputStream.close();

            audioTrack = new AudioTrack(
                    AudioManager.STREAM_MUSIC,
                    11025,
                    AudioFormat.CHANNEL_IN_MONO,
                    AudioFormat.ENCODING_PCM_16BIT,
                    bufferSizeInBytes,
                    AudioTrack.MODE_STREAM);

            playBtn.setText(getString(R.string.stop));
            audioTrack.play();
            audioTrack.write(audioData, 0, bufferSizeInBytes);
                playbuttonstatus = false;

        } catch (FileNotFoundException e){
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    else {
        playBtn.setText(getString(R.string.play));
        playbuttonstatus = true;
        audioTrack.pause();
        audioTrack.flush();
    }
}

如何使用按钮启动audiotrack并停止audiotrack？

2 个答案: