Android 进阶之【chapter-11】 Service

android:enabled=”true” 能否被系统实例化
android:exported=”true” 能否被其他程序访问

工程：RemoteService和RemoteserviceAIDL

一：服务分两种（Service和IntentService，IntentService中的onHandlerInt是默认在一个线程里运行相当于ASYN的doinbackground）

• 1：本地的服务(LocalService)
• 2：远程服务：进程间的服务(比如后台播放音乐)(要在布局文件中加入android:process=”：yangjie.remoteservice”)//里面的名字可以随意，但是必须是小写，和：开头，加了这句代码之后，这个服务就会新开一个进程来运行了

二：服务被杀死的概率

foreground process
visible process
service process //所以说服务还是有很大的概率会被杀死的
background process
empty process

三：服务中onStrartcommand（）方法中的返回值

• 1: START_STICKY_COMPATIBILITY 不保证被系统杀死之后，会自动启动
• 2: START_STICKY 服务被杀死后，系统会自动创建并且启动，但不会传输intent对象
• 3: START_NOT_STICKY 服务被杀死后系统不会重写创建和启动
• 4: START_REDELIVER_INTENT 服务被杀死后，系统会重写创建并启动，且会传输最近一次使用的intent

四:本地服务的绑定服务(只有通过绑定才能调用Service中的方法)

定义一个类继承于Binder
在服务中务中声明一个类的对象
定义一个该类的实列，并在onCreate（）中实例化
在MainActivity中创建ServiceConnection接口,在Onserviceconnnected中调用服务
绑定服务
startService(new Intent(this, LocalService. class)); //只有startService才能启动onStartCommand（）方法以及它的子类方法onHandleIntent（）;
bindService(new Intent(this, LocalService.class),coon ,BIND_AUTO_CREATE);//绑定服务

package com.example.yangjie.service;import android.app.Service;import android.content.Intent;import android.os.Binder;import android.os.IBinder;public class LocalService extends Service {    private  LocalBinder  mBinder=null;    public LocalService() {    }    @Override    public void onCreate() {        super .onCreate();        //3:在oncreate中实例化这个对象        mBinder =new LocalBinder();    }    @Override    public IBinder onBind(Intent intent) {//绑定服务和Activity绑定在一起        //4:在onBind（）方法张返回该对象        return  mBinder;    }    //1:定义一个类继承于Binder   public  class  LocalBinder extends Binder{    //2:在服务中声明一个类的对象      LocalService getService(){          return  LocalService.this;      }    }    //要反回的一个字符串    public  String getString(){        return  "ABC";    }}=================================================private  ServiceConnection  coon=new ServiceConnection() {    @Override    public void onServiceConnected(ComponentName name, IBinder service) {    //服务连接成功调用次方法        //强制类型转换        LocalService.LocalBinder binder=(LocalService.LocalBinder)service;        LocalService ser=binder.getService();        String  str=ser.getString();        Toast.makeText(MainActivity. this,str,Toast. LENGTH_SHORT).show();    }    @Override    public void onServiceDisconnected(ComponentName name) {        //断开连接成功调用次方法    }};

五：远程服务的绑定以及回调(这个非常重要)

1:Messenger (Messenger代码是少于AIDL但功能却不如AIDL)
2:AIDL(只有AIDL才可以通过回调从Service传数据回Activity)

Service代码

package com.example.yangjie.remoteserviceaidl;import android.app.Notification;import android.app.Service;import android.content.Intent;import android.os.IBinder;import android.os.RemoteException;import android.support.v7.app.NotificationCompat;public class RemodeService extends Service {    private IRemoteCallback mcallback ;    @Override    public void onCreate() {        super .onCreate();        Notification notification=null;        NotificationCompat.Builder builder=new NotificationCompat.Builder(this);        builder.setSmallIcon(R.mipmap.ic_launcher);        builder.setContentTitle("计步器");        builder.setContentText("当前步数：0");        notification=builder.build();        startForeground(1 ,notification);//将服务转变为前台进程，这样就不容易被系统回收    }    public RemodeService() {    }    @Override    public IBinder onBind(Intent intent) {        return  binder;    }    /**     * 第二步：实现AIDL文件同名Stub     */   private   IRemodeService.Stub binder=new IRemodeService.Stub() {        @Override         public void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat, double aDouble, String aString) throws RemoteException {         }        @Override        public boolean date(String content) throws RemoteException {            if("看电影".equals(content)){                //调用回调接口的方法,相当于反向调用Activity的方法                if(mcallback!=null){                    mcallback.invite( "唱歌");                }                return false;            }else if("吃饭".equals(content)){                return true;            }            return false;        }        @Override        public void registcallback(IRemoteCallback callback) throws RemoteException {               mcallback=callback;        }        @Override        public void unregistcallback(IRemoteCallback callback) throws RemoteException {            mcallback=null;        }        @Override        public String getReuslt(String text) throws RemoteException {            if("a".equals(text)){                return "今天是个艳阳天" ;            }            return  null;        }        @Override         public int add(int a, int b) throws RemoteException {             return addInt(a,b);         }     };    public   int  addInt(int a ,int b){        return  a+b;    }}

Activity代码

package com.example.yangjie.remoteserviceaidl;import android.content.ComponentName;import android.content.Intent;import android.content.ServiceConnection;import android.os.IBinder;import android.os.RemoteException;import android.support.v7.app.AppCompatActivity;import android.os.Bundle;import android.util.Log;import android.view.View;import android.widget.TextView;import android.widget.Toast;public class MainActivity extends AppCompatActivity {    private TextView mshow ,mfilm ,mfood ;    private  IRemodeService iRemodeService;    private  final  static  String LOG_TAG="MainActivity";    @Override    protected void onCreate(Bundle savedInstanceState) {        super .onCreate(savedInstanceState);        setContentView(R.layout.activity_main);        mshow =(TextView)findViewById(R.id.activity_main_btn_show);        mfilm =(TextView)findViewById(R.id.activity_main_btn_film);        mfood =(TextView)findViewById(R.id.activity_main_btn_food);        findViewById(R.id.activity_main_btn_start).setOnClickListener( new View.OnClickListener() {            @Override            public void onClick(View v) {                int a=519;                int b=1;                try {                   int total= iRemodeService.add(a,b);                    mshow.setText("两个数的和为："+total+iRemodeService .getReuslt("a"));                } catch (RemoteException e) {                    e.printStackTrace();                }            }        });    }    public  void  setOnclick(View view){        switch (view.getId()){            case R.id.activity_main_btn_film:                try {                    boolean result=iRemodeService.date( "看电影");                    if(result){                       Toast. makeText(MainActivity.this,"女神和我去看电影",Toast.LENGTH_SHORT ).show();                    }                } catch (RemoteException e) {                    e.printStackTrace();                }                break;            case R.id.activity_main_btn_food:                try {                    boolean result=iRemodeService.date( "吃饭");                    if(result){                        Toast. makeText(MainActivity.this,"女神和我去吃饭",Toast.LENGTH_SHORT ).show();                    }                } catch (RemoteException e) {                    e.printStackTrace();                }                break;        }    }    @Override    protected void onStart() {        super .onStart();        //绑定服务        Intent intent= new Intent( this,RemodeService. class);        bindService(intent,coon,BIND_AUTO_CREATE);    }    @Override    protected void onStop() {        super .onStop();        unbindService(coon);    }    private ServiceConnection coon =new ServiceConnection() {        @Override        public void onServiceConnected(ComponentName name, IBinder service) {            iRemodeService=IRemodeService.Stub.asInterface(service);            try {                iRemodeService.registcallback( iRemoteCallback);            } catch (RemoteException e) {                e.printStackTrace();            }        }        @Override        public void onServiceDisconnected(ComponentName name) {            iRemodeService=null;        }    };private  IRemoteCallback iRemoteCallback =new IRemoteCallback.Stub() {    @Override    public void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat, double aDouble, String aString) throws RemoteException {    }    @Override    public void invite(String content) throws RemoteException {        //Toast.makeText(MainActivity.this,"女神邀请我去"+content,Toast.LENGTH_LONG).show();        Log.v(LOG_TAG ,"--------------->女神邀请我去" +content);    }};}

aidl代码

package com.example.yangjie.remoteserviceaidl;import com.example.yangjie.remoteserviceaidl.IRemoteCallback;interface IRemodeService {    void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat,            double aDouble, String aString);            //第一步：定义要的函数            int add(int a,int b);            String getReuslt(String text);            boolean  date(String content);            //注册回调方法            void registcallback(IRemoteCallback  callback);            //解除回调方法            void unregistcallback(IRemoteCallback  callback);}

回调时的代码

package com.example.yangjie.remoteserviceaidl;interface IRemoteCallback {    void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat,            double aDouble, String aString);            void invite(String content);}