import java.io.File;

import android.app.Activity;
import android.media.MediaPlayer;
import android.media.MediaPlayer.OnCompletionListener;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.os.Environment;
import android.os.Handler;
import android.os.Message;
import android.util.Log;
import android.view.Menu;
import android.view.MotionEvent;
import android.view.View;
import android.view.View.OnClickListener;
import android.view.View.OnTouchListener;
import android.widget.Button;
import android.widget.TextView;

public class MainActivity extends Activity {

 private MediaRecorder recoder = null;
 private MediaPlayer player = null;
 private String theMediaPath;

 TextView tv = null;
 TextView tvRecord = null;
 Button testBtn = null;
 Button testBtn2 = null;
 Button stopBtn = null;
 Button playBtn = null;

 @Override
 protected void onCreate(Bundle savedInstanceState) {
  super.onCreate(savedInstanceState);
  setContentView(R.layout.activity_main);
  tv = (TextView)findViewById(R.id.textView1);
  tvRecord = (TextView)findViewById(R.id.tvRecord);
  testBtn = (Button)findViewById(R.id.button1);
  testBtn2 = (Button)findViewById(R.id.button2);
  stopBtn = (Button)findViewById(R.id.buttonStop);
  playBtn = (Button)findViewById(R.id.buttonPlay);

  testBtn2.setOnTouchListener(new OnTouchListener() {
   @Override
   public boolean onTouch(View v, MotionEvent event) {
    Log.i("testactivity", "setOnTouchListener:"+event.getAction());
    switch(event.getAction()) {
     case MotionEvent.ACTION_UP: {
      Log.i("testactivity", "停止錄音");
      stopRecording();
      break;
     }
     case MotionEvent.ACTION_DOWN: {
      Log.i("testactivity", "開始錄音");
      startRecording();
      break;
     }
     default: break;
    }
    return false;
   }
  });

  
  testBtn.setOnClickListener(new OnClickListener() {
   public void onClick(View arg0) {
    startRecording();
    testBtn.setEnabled(false);
    stopBtn.setEnabled(true);
   }
  });

  stopBtn.setEnabled(false);

  stopBtn.setOnClickListener(new OnClickListener() {
   public void onClick(View arg0) {
    stopRecording();
    testBtn.setEnabled(true);
    playBtn.setEnabled(true);
    stopBtn.setEnabled(false);
   }
  });

  
  playBtn.setOnClickListener(new OnClickListener() {
   public void onClick(View arg0) {
    playRecordFile(theMediaPath);
    stopBtn.setEnabled(true);
   }
  });
 }

 protected void playRecordFile(String _file) {
  try {
   File f = new File(_file);
   if(!f.exists()) {
    tv.setText("文件不存在:" + _file);
    return;
   }
  } catch(Exception e) {
   Log.i("testactivity", e.getMessage());
  }
  try {
   player = new MediaPlayer();
   player.setDataSource(_file);
   player.prepare();
   player.setOnCompletionListener(new OnCompletionListener() {
    public void onCompletion(MediaPlayer arg0) {
     tv.setText("播放完畢");
     stopBtn.setEnabled(false);
    }
   });

   player.start();
  } catch(Exception e) {
   Log.e("testactivity", "play failed:" + e.getMessage());
  }
 }

 /**
  * 停止錄音處理
  */
 protected void stopRecording() {

  if(recoder != null) {
   Log.i("testactivity", "停止錄音");
   recoder.stop();
   recoder.release();
   recoder = null;
   endtime = System.currentTimeMillis();
   _handleRecordComplete();
  }
  if(player != null) {
   Log.i("testactivity", "停止播放");
   player.stop();
   player.release();
   player = null;
  }
 }

 
 /**
  * 開始錄音處理
  */
 protected void startRecording() {

  theMediaPath = Environment.getExternalStorageDirectory().getAbsolutePath();
  theMediaPath += "/audiotest.3gp";

  recoder = new MediaRecorder();
  recoder.setAudioSource(MediaRecorder.AudioSource.MIC);
  recoder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
  recoder.setOutputFile(theMediaPath);
  recoder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);

  starttime = System.currentTimeMillis();
  updateMicStatus();

  try {
   recoder.prepare();
   recoder.start();
   _handleRecordStart();
  } catch (Exception e) {
   Log.e("testactivity", "prepared failed:" + e.getMessage());
   _handleRecordStartError(e);
  }

 }

 //定時器
 private static long maxtime = 30*1000; //30秒
 private long starttime = 0l;
 private long endtime = 0l;
 private final Handler mHandler = new Handler(); 
    private Runnable mUpdateMicStatusTimer = new Runnable() { 
        public void run() { 
         //判斷是否超時
         if(starttime > 0 && System.currentTimeMillis() - starttime > maxtime) {
          Log.e("testactivity", "超時的錄音時間，直接停止");
          stopRecording();
          return;
         }

         //更新分貝狀態
            updateMicStatus(); 
        } 
    }; 

    /**
     * 更新話筒狀態 分貝是也就是相對響度 分貝的計算公式K=20lg(Vo/Vi) Vo當前振幅值 Vi基準值為600：我是怎么制定基準值的呢？ 當20
     * * Math.log10(mMediaRecorder.getMaxAmplitude() / Vi)==0的時候vi就是我所需要的基準值
     * 當我不對著麥克風說任何話的時候，測試獲得的mMediaRecorder.getMaxAmplitude()值即為基準值。
     * Log.i("mic_", "麥克風的基準值：" + mMediaRecorder.getMaxAmplitude());前提時不對麥克風說任何話
     */ 
    private int BASE = 600; 
    private int SPACE = 300;// 間隔取樣時間

    private void updateMicStatus() { 
        if (recoder != null) { 
            // int vuSize = 10 * mMediaRecorder.getMaxAmplitude() / 32768; 
            int ratio = recoder.getMaxAmplitude() / BASE; 
            int db = 0;// 分貝 
            if (ratio > 1) 
                db = (int) (20 * Math.log10(ratio)); 

           
            _handleRecordVoice(db);

            mHandler.postDelayed(mUpdateMicStatusTimer, SPACE); 
            /*
             * if (db > 1) { vuSize = (int) (20 * Math.log10(db)); Log.i("mic_",
             * "麥克風的音量的大小：" + vuSize); } else Log.i("mic_", "麥克風的音量的大小：" + 0);
             */ 
        } 
    }
 

 private void _handleRecordStart() {
  //開始錄音的接收函數
  tv.setText("開始錄音...");
  //starttime 開始時間
 }

 private void _handleRecordStartError(Exception e) {
  //開始錄音的接收函數失敗
  tv.setText("開始錄音失敗:" + e.getMessage());
 }

 private void _handleRecordComplete() {
  //結束錄音
  tv.setText("停止錄音:" + theMediaPath);
 }

 private void _handleRecordVoice(int _db) {
  //聲音事件偵聽，轉換成分貝
  tvRecord.setText(""+_db);
 }

 @Override
 public boolean onCreateOptionsMenu(Menu menu) {
  // Inflate the menu; this adds items to the action bar if it is present.
  getMenuInflater().inflate(R.menu.main, menu);
  return true;
 }

}