Android AudioRecord初始化失败

Question

I'm creating application for Android that listen phone call. Problem is that initialization fail.

My log:

E/AudioRecord﹕ Could not get audio input for record source 3
E/AudioRecord-JNI﹕ Error creating AudioRecord instance: initialization check failed.
E/android.media.AudioRecord﹕ Error code -20 when initializing native AudioRecord object.

My code:

public AudioRecord recorder;

private int sampleRate = 16000;
private int channelConfig = AudioFormat.CHANNEL_IN_MONO;
private int audioFormat = AudioFormat.ENCODING_PCM_16BIT;
int minBufSize = AudioRecord.getMinBufferSize(sampleRate, channelConfig, audioFormat);

recorder = new AudioRecord(MediaRecorder.AudioSource.VOICE_DOWNLINK, sampleRate, channelConfig, audioFormat, minBufSize * 10);
recorder.startRecording();

EDIT: I want only DOWNLINK

Answer 1

You should use MediaRecorder instade of AudioRecord, Hear is one example for record audio and save in your sdCard.

    MediaRecorder myAudioRecorder;
    outputFile = Environment.getExternalStorageDirectory().getAbsolutePath()    + "/recording.3gp";
    myAudioRecorder=new MediaRecorder();
    myAudioRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
    myAudioRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
    myAudioRecorder.setAudioEncoder(MediaRecorder.OutputFormat.AMR_NB);
    myAudioRecorder.setOutputFile(outputFile);

You could Start recording on button click event using below code

           try {
                myAudioRecorder.prepare();
                myAudioRecorder.start();
            }

            catch (IllegalStateException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }

            catch (IOException e) {
                // TODO Auto-generated catch block
                e.printStackTrace();
            }