1、请求录制音频权限

<user-permission android:name="android.permission.RECORD_AUDIO"/>

RECORD_AUDIO 权限从6.0后需要进行用户授权，通过ActivityCompat.requestPermissions();

2、创建运行MediaRecorder

2.1 设置音频源setAudioSource(int audio_source) ，多少情况使用MediaRecorder.AudioSource.MIC

2.2 设置输出音频文件格式 setOutputFormat(int output_format)

*(Android 8.0 开始支持MPEG2_TS 格式)

2.3  设置输出文件名 setOutputFile(String filepath) 

2.4 设置音频编码器 setAudioEncoder(int audio_encoder)

2.5 通过完成初始化 prepare()

2.6  start()

3 停止释放资源

stop()  release()

4、创建MediaPlayer 

MediaPlayer mediaPlayer=new MediaPlayer();
mediaPlayer.setDataSource(recordFile.getPath());
                    mediaPlayer.prepare();
                    mediaPlayer.start();
                    mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
                        @Override
                        public void onCompletion(MediaPlayer mp) {
                            mp.reset();
                        }
                    });

package com.rexkell.mediaapplication;

import android.media.MediaPlayer;
import android.media.MediaRecorder;
import android.os.Bundle;
import android.support.annotation.Nullable;
import android.support.v7.app.AppCompatActivity;
import android.view.View;
import android.widget.Button;

import java.io.File;
import java.io.IOException;

/**
 * author: rexkell
 * explain:MediaRecord 录制音频
 */
public class MediaRecordActivity extends AppCompatActivity {
    private boolean isRecording=false;
    MediaRecorder mediaRecorder;
    MediaPlayer mediaPlayer;
    File  recordFile;
    @Override
    protected void onCreate(@Nullable Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.ac_mediarecord);
        init();
    }
    public void init(){
        mediaRecorder=new MediaRecorder();
        //设置音频的来源
        mediaRecorder.setAudioSource(MediaRecorder.AudioSource.MIC);
        //设置音频的输出格式
        mediaRecorder.setOutputFormat(MediaRecorder.OutputFormat.AMR_WB);
        //设置音频文件的编码
        mediaRecorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_WB);
        mediaPlayer=new MediaPlayer();
        recordFile=new File(getExternalFilesDir(null).getPath()+"/test.amr");


    }
    public void record(View v){
        isRecording=!isRecording;
        String text=isRecording?"暂停":"录制";
        ((Button)v).setText(text);
        if (isRecording){
            startRecord();
        }else {
            stopRecord();
        }
    }
    public void play(View v){

                if (mediaPlayer.isPlaying()){
                    return;
                }
                //设置数据源
                try {
                    mediaPlayer.setDataSource(recordFile.getPath());
                    mediaPlayer.prepare();
                    mediaPlayer.start();
                    mediaPlayer.setOnCompletionListener(new MediaPlayer.OnCompletionListener() {
                        @Override
                        public void onCompletion(MediaPlayer mp) {
                            mp.reset();
                        }
                    });
                } catch (IOException e) {
                    e.printStackTrace();
                }


    }
    public void startRecord(){
        if (recordFile.exists()){
            recordFile.delete();
        }
            try {
                recordFile.createNewFile();
            } catch (IOException e) {
                e.printStackTrace();
            }

        mediaRecorder.setOutputFile(recordFile.getPath());
        try {
            mediaRecorder.prepare();
            mediaRecorder.start();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public void stopRecord(){
        if (mediaRecorder!=null&&isRecording){
            mediaRecorder.stop();
            mediaRecorder.release();
            mediaRecorder=null;
        }
    }
    public void stopPlay(){
         if(mediaPlayer!=null){
             mediaPlayer.stop();
             mediaPlayer.release();
             mediaPlayer=null;
         }
    }
}