title: getAmplitude isn't working
body: <p>When I try to work  it's show on textviev "0.0" value.
  I get codes from this web site mostly
  I get permissions to 
       <code>&lt;uses-permission android:name="android.permission.RECORD_AUDIO" /&gt;</code>
  ı give permission on setting-applications-mic
  it's returned value "0.0"
  how really works getAmplitude();
  can some one explain</p>
  
  <pre><code>static final private double EMA_FILTER = 0.6;
  TextView text;
  Button buton;
  Handler handler;
  boolean state = false;
  @Override
  protected void onCreate(Bundle savedInstanceState){
      super.onCreate(savedInstanceState);
      setContentView(R.layout.activity_karpuz_sec);
      text = (TextView) findViewById(R.id.text);
      buton = (Button) findViewById(R.id.button);
      handler = new Handler();
      buton.setOnClickListener(new View.OnClickListener() {
          @Override
          public void onClick(View view) {
              if(!state){
                  try {
                      start();
                  } catch (IOException e) {
                      e.printStackTrace();
                  }
              }
              else
                  stop();
          }
      });
  }
  Runnable runnable = new Runnable() {
      @Override
      public void run() {
          while (!state){
              text.setText(Double.toString(getAmplitudeEMA()));;
              handler.postDelayed(this,100);
          }
      }
  };
  
  private MediaRecorder mRecorder = null;
  private double mEMA = 0.0;
  
  public void start() throws IOException {
      if (mRecorder == null) {
          mRecorder = new MediaRecorder();
          mRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
          mRecorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
          mRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
          mRecorder.setOutputFile("/dev/null");
          mRecorder.prepare();
          mRecorder.start();
          mEMA = 0.0;
          state = true;
          Toast.makeText(getApplicationContext(),"Ses Ölçümü Başladı",Toast.LENGTH_SHORT).show();
          buton.setText("DURDUR");
          text.setText(Double.toString(getAmplitudeEMA()));
  
      }
  }
  
  public void stop() {
      if (mRecorder != null) {
          mRecorder.stop();
          mRecorder.release();
          mRecorder = null;
          state = false;
          Toast.makeText(getApplicationContext(),"Ses Ölçümü Durdu",Toast.LENGTH_SHORT).show();
          buton.setText("BAŞLAT");
      }
  }
  
  public double getAmplitude() {
      if (mRecorder != null)
          return  (mRecorder.getMaxAmplitude()/2700.0);
      else
          return 0;
  }
  
  public double getAmplitudeEMA() {
      double amp = getAmplitude();
      mEMA = EMA_FILTER * amp + (1.0 - EMA_FILTER) * mEMA;
      return mEMA;
  }
  </code></pre>
  
  <p>}</p>