service入门—电话监听器

1、继承Service类

2、在清单文件进行配置(因为Service属于四大组件之一)

 <service android:name=".PhoneStatusService">
 </service>

3、因为要监听电话状态，并且把文件存在外存中,所以权限配置为

 <uses-permission android:name="android.permission.READ_PHONE_STATE"/>
     <uses-permission android:name="android.permission.RECORD_AUDIO"/>
     <uses-permission android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>

4、开启一个服务的代码(像activity、broadcastReceive都使用intent进行开启)

 //开启服务
 Intent intent = new Intent(this, PhoneStatusService.class);
 startService(intent);

5、通过媒体监听电话情况的Service的代码

 package com.example.callstatuslistener;

 import java.io.IOException;

 import android.app.Service;
 import android.content.Intent;
 import android.media.MediaRecorder;
 import android.os.IBinder;
 import android.telephony.PhoneStateListener;
 import android.telephony.TelephonyManager;
 /**
  * @desc 服务一旦被开启，则会长期运行在后台，除非手工停止掉
  * @author zyh
  *
  */
 public class PhoneStatusService extends Service {
     //服务被创建了
     @Override
     public void onCreate() {
         // TODO Auto-generated method stub
         super.onCreate();
         System.out.println("服务开启");
         //电话管理器,它能够获取电话的各种信息
         TelephonyManager tm = (TelephonyManager) getSystemService(TELEPHONY_SERVICE);
         //监听手机的通话状态的变化
         tm.listen(new MyPhoneListener(), PhoneStateListener.LISTEN_CALL_STATE);
     }

     private class MyPhoneListener extends PhoneStateListener{

         private MediaRecorder recorder;
         @Override
         public void onCallStateChanged(int state, String incomingNumber) {
             // TODO Auto-generated method stub
             super.onCallStateChanged(state, incomingNumber);
             try {
                 switch(state){
                 case TelephonyManager.CALL_STATE_IDLE:   //空闲状态，也没有响铃
                     if(recorder != null){   //释放资源
                         recorder.stop();
                         recorder.reset();   // You can reuse the object by going back to setAudioSource() step
                         recorder.release(); // Now the object cannot be reused
                     }
                     break;
                 case TelephonyManager.CALL_STATE_RINGING: //响铃状态
                     System.out.println("发现来电号码为:" + incomingNumber);
                     recorder = new MediaRecorder();
                     //设置录制的音频源,从话筒中获取声音,只能录制自己的
                     recorder.setAudioSource(MediaRecorder.AudioSource.MIC);
                     //设置它的文件格式
                     recorder.setOutputFormat(MediaRecorder.OutputFormat.THREE_GPP);
                     //设置的音频的编码格式
                     recorder.setAudioEncoder(MediaRecorder.AudioEncoder.AMR_NB);
                     //文件保存的位置
                     recorder.setOutputFile("/sdcard/" + System.currentTimeMillis() + ".3gp");
                     recorder.prepare();

                     break;
                 case TelephonyManager.CALL_STATE_OFFHOOK:   //通话状态
                     if(recorder != null){
                         recorder.start();
                     }
                     break;
                 }
             } catch (IOException e) {
                 // TODO Auto-generated catch block
                 e.printStackTrace();
             }
         }

     }

     //服务销毁了
     @Override
     public void onDestroy() {
         // TODO Auto-generated method stub
         super.onDestroy();
         System.out.println("服务销毁");
     }

     @Override
     public IBinder onBind(Intent intent) {
         // TODO Auto-generated method stub
         return null;
     }

 }

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