如何在遊戲/應用程序中記錄或者從手機發生的任何事情，而不是通過麥克風錄音？

Question

我試圖錄制來自手機的音頻，而不是使用麥克風，當然使用MediaRecorder。現在我看到有一種方法可以讓我設置音頻源mediaRecorder.setAudioSource()。它具有我可以使用的常數，如攝像機，麥克風，默認等。我想知道默認設置是否允許我記錄電話系統中播放的任何內容？還是有另一種方式？無論什麼可以幫助，提前感謝。

Answer 1

有完整的代碼錄音並保存文件在內存中

public class AudioRecord extends AppCompatActivity 
    { 
     Button play, stop, record; 
     //private MediaRecorder myAudioRecorder; 
     //private String outputFile = null; 
     File audiofile = null; 
     //MediaRecorder recorder = null; 
     Uri fileUri = null; 

     Chronometer myChronometer; 
     private MediaRecorder mRecorder = null; 
     private static final String LOG_TAG = "AudioRecordTest"; 
     //private static String mFileName = null; 
     private MediaPlayer mPlayer = null; 

     @Override 
     protected void onCreate(Bundle savedInstanceState) 
     { 
      super.onCreate(savedInstanceState); 
      setContentView(R.layout.record_audio); 
      myChronometer = (Chronometer) findViewById(R.id.chronometer); 
      play = (Button) findViewById(R.id.buttonPlay); 
      stop = (Button) findViewById(R.id.buttonStop); 
      record = (Button) findViewById(R.id.buttonRecord); 

      stop.setEnabled(false); 
      play.setEnabled(false); 
      long current = System.currentTimeMillis(); 
      File sampleDir = Environment.getExternalStorageDirectory(); 
      try { 
       audiofile = File.createTempFile("sound"+current, ".3gp", sampleDir); 
      } catch (IOException e) { 
       Log.e("AAA", "sdcard access error"); 
       return; 
      } 
      record.setOnClickListener(new View.OnClickListener() 
      { 
       @Override 
       public void onClick(View v) 
       { 

        myChronometer.start(); 
        mRecorder = new MediaRecorder(); 
        mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC); 
        mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP); 
        mRecorder.setOutputFile(audiofile.getAbsolutePath()); 
        mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB); 

        try 
        { 
         mRecorder.prepare(); 
        } 
        catch(IOException e) 
        { 
         Log.e(LOG_TAG, "prepare() failed"); 
        } 

        mRecorder.start(); 


        record.setEnabled(false); 
        stop.setEnabled(true); 

        Toast.makeText(getApplicationContext(), "Recording started", Toast.LENGTH_LONG).show(); 
       } 
      }); 

      stop.setOnClickListener(new View.OnClickListener() 
      { 
       @Override 
       public void onClick(View v) 
       { 
        mRecorder.stop(); 
        mRecorder.release(); 
        mRecorder = null; 

        stop.setEnabled(false); 
        play.setEnabled(true); 
        addRecordingToMediaLibrary(); 
        Toast.makeText(getApplicationContext(), "Audio recorded successfully", Toast.LENGTH_LONG).show(); 
        myChronometer.stop(); 
        myChronometer.setBase(SystemClock.elapsedRealtime()); 
       } 
      }); 

      play.setOnClickListener(new View.OnClickListener() 
      { 
       @Override 
       public void onClick(View v) throws IllegalArgumentException, SecurityException, IllegalStateException 
       { 
        Intent data = new Intent(); 
        // data.putExtra("result",mFileName); 
        data.setData(fileUri); 
        //data.setData(Uri.fromFile(new File(mFileName))); 
        setResult(RESULT_OK, data); 

        finish(); 
        // startPlaying(); 
       } 
      }); 
     } 

     protected void addRecordingToMediaLibrary() { 
      ContentValues values = new ContentValues(4); 
      long current = System.currentTimeMillis(); 
      values.put(MediaStore.Audio.Media.TITLE, "audio" + audiofile.getName()); 
      values.put(MediaStore.Audio.Media.DATE_ADDED, (int) (current/1000)); 
      values.put(MediaStore.Audio.Media.MIME_TYPE, "audio/3gpp"); 
      values.put(MediaStore.Audio.Media.DATA, audiofile.getAbsolutePath()); 
      ContentResolver contentResolver = getContentResolver(); 

      Uri base = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI; 
      Uri newUri = contentResolver.insert(base, values); 

      sendBroadcast(new Intent(Intent.ACTION_MEDIA_SCANNER_SCAN_FILE, newUri)); 
      M.L("Added File " + newUri); 
      //Toast.makeText(this, "Added File " + newUri, Toast.LENGTH_LONG).show(); 
      fileUri=newUri; 
     } 


// Record audio XML 
<?xml version="1.0" encoding="utf-8"?> 
<LinearLayout xmlns:android="http://schemas.android.com/apk/res/android" 

       android:layout_width="match_parent" 
       android:layout_height="match_parent" 
       android:orientation="vertical"> 

    <include layout="@layout/toolbar"></include> 

    <RelativeLayout 
     android:layout_width="match_parent" 
     android:layout_height="match_parent" 
     > 

     <LinearLayout 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:layout_above="@+id/imageView" 
      android:layout_alignParentTop="true" 
      android:background="#050505" 
      android:orientation="vertical" 
      android:padding="20dp"> 

      <TextView 
       android:id="@+id/textView2" 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:layout_centerHorizontal="true" 
       android:layout_gravity="center_horizontal" 
       android:drawableLeft="@drawable/mix_record" 
       android:gravity="center" 
       android:text=" Recoding... " 
       android:textColor="@color/white" 
       android:textSize="18sp"/> 

      <Chronometer 
       android:id="@+id/chronometer" 
       android:layout_width="fill_parent" 
       android:layout_height="match_parent" 
       android:layout_gravity="center_horizontal" 
       android:gravity="center" 
       android:textColor="@color/white" 

       android:textSize="60sp" 
       /> 


     </LinearLayout> 


     <ImageView 
      android:id="@+id/imageView" 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:layout_above="@+id/linearLayout5" 
      android:layout_alignParentLeft="true" 
      android:layout_alignParentStart="true" 
      android:background="#171A1D" 
      android:src="@drawable/a_microphone"/> 

     <LinearLayout 
      android:id="@+id/linearLayout5" 
      android:layout_width="match_parent" 
      android:layout_height="wrap_content" 
      android:layout_alignParentBottom="true" 
      android:background="#9b9b9b" 
      android:gravity="center" 
      android:orientation="horizontal" 
      android:padding="16dp"> 

      <Button 
       android:id="@+id/buttonRecord" 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:layout_alignParentLeft="true" 
       android:layout_marginRight="7dp" 
       android:text="Record"/> 

      <Button 
       android:id="@+id/buttonStop" 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:layout_alignTop="@+id/button" 
       android:layout_centerHorizontal="true" 
       android:text="Stop"/> 

      <Button 
       android:id="@+id/buttonPlay" 
       android:layout_width="wrap_content" 
       android:layout_height="wrap_content" 
       android:layout_alignParentRight="true" 
       android:layout_alignTop="@+id/button2" 
       android:layout_marginLeft="7dp" 
       android:text="send"/> 
     </LinearLayout> 


    </RelativeLayout> 
</LinearLayout>