java - 如何使用Java在Android中创建30秒自动音频剪辑

Question

我正在做一个有趣的休闲项目

在android studio中，我尝试实现按钮单击，以启动自动30秒的音频记录，用户可以在该时间段内执行或说出任何操作。

剪辑完成后，它会自动播放并提供直接保存或下载到设备的功能

我还没有开始，我对应该研究API中的哪些特定方法感到好奇？？？

任何建议将是惊人的谢谢。

Answer 1

尝试这样的事情:

private MediaRecorder mMediaRecorder;
private static final long UPDATE_INTERVAL = 100;
private Sync mSync;
private boolean mIsRecording = false;
private long mStartTime = 0;
private long mStopTime = 0;
private String mFileName;

private void startRecord() {
    startRecording();
    mSync = new Sync(new Runnable() {

        @Override
        public void run() {
            if (!mIsRecording||!isAdded())
                return;
            long currentTime = System.currentTimeMillis();
            if (currentTime-mStartTime>AppConstants.MAX_RECORD_DURATION_S*1000){
                stopRecord();
                updateLayoutVisibility();
                return;                                 
            }
            String str = getString(R.string.recording_template,(currentTime-mStartTime)/1000,AppConstants.MAX_RECORD_DURATION_S);
            mTextSeconds.setText(str);
            mSync.next();
        }
    },UPDATE_INTERVAL);
    mSync.now();
    mLayoutButtonsStartRecord.setVisibility(View.GONE);
    mLayoutButtonsRecord.setVisibility(View.VISIBLE);
}


private void stopRecord() {
    mSync.stop();
    mIsRecording = false;
    mStopTime = System.currentTimeMillis();
    mMediaRecorder.stop();
    mMediaRecorder.release();
    mMediaRecorder = null;      
}

private void startRecording() {
    if (mMediaRecorder != null) {
        mMediaRecorder.release();
    }
    mFileName = getTempRecordFileName();
    if (mFileName==null){
        dismiss();
        return;
    }
    mIsRecording = true;
    mMediaRecorder = new MediaRecorder();
    mMediaRecorder.setAudioSource(AudioSource.MIC);
    mMediaRecorder.setOutputFormat(OutputFormat.MPEG_4);
    mMediaRecorder.setAudioEncoder(AudioEncoder.AAC);
    mMediaRecorder.setAudioChannels(1);

    mMediaRecorder.setOutputFile(mFileName);
    try {
        mMediaRecorder.prepare();
        mMediaRecorder.start();
        mStartTime = System.currentTimeMillis();
    } catch (IOException e) {
        Toast.makeText(getActivity(),
                R.string.error_failed_start_recording, Toast.LENGTH_LONG)
                .show();
        Log.d(TAG, "Failed start recorder", e);
        mMediaRecorder.release();
        mMediaRecorder = null;
        dismiss();
        return;
    }
}

private class Sync{
    private Handler handler = new Handler();
    private Runnable task;
    private long period;

    public Sync(Runnable task,long period){
        this.task = task;
        this.period = period;
        handler.removeCallbacks(task);
    }
    public void now(){
        task.run();
    }

    public void next(){
        handler.postDelayed(task, period);
    }
    public void stop(){
        handler.removeCallbacks(task);
    }
}

@Override
public void onPause() {
    super.onPause(); 
    if (mMediaRecorder != null) {
        mMediaRecorder.release();
        mMediaRecorder = null;
    }
    if (mSync!=null){
       mSync.stop();
    }

}