在实际开发中可能需要用到两个Service相互监视的情况，本示例就是实现此功能以作参考。
服务A：
public class ServiceA extends Service {
private static final String TAG = ServiceA.class.getSimpleName();
MyBinder mBinder;
MyServiceConnection mServiceConnection;
PendingIntent mPendingIntent;
@Override
public void onCreate() {
super.onCreate();
if(mBinder==null)
{
mBinder=new MyBinder();
}
mServiceConnection=new MyServiceConnection();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
ServiceA.this.bindService(new Intent(ServiceA.this,ServiceB.class),mServiceConnection, Context.BIND_IMPORTANT);
mPendingIntent=PendingIntent.getService(this,0,intent,0);
Notification.Builder builder=new Notification.Builder(this);
builder.setTicker("守护服务A启动中")
.setContentText("我是来守护服务B的")
.setContentTitle("守护服务A")
.setSmallIcon(R.mipmap.ic_launcher)
.setContentIntent(mPendingIntent)
.setWhen(System.currentTimeMillis());
Notification notification=builder.build();
startForeground(startId,notification);
return START_STICKY;
}
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
public class MyBinder extends IBridgeInterface.Stub {
@Override
public String getName() throws RemoteException {
return "name:"+TAG;
}
}
class MyServiceConnection implements ServiceConnection {
@Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
String name=null;
try {
name= IBridgeInterface.Stub.asInterface(iBinder).getName();
} catch (RemoteException e) {
e.printStackTrace();
}
Toast.makeText(ServiceA.this,name+"连接成功",Toast.LENGTH_SHORT).show();
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
Toast.makeText(ServiceA.this,TAG+"断开连接",Toast.LENGTH_SHORT).show();
ServiceA.this.startService(new Intent(ServiceA.this,ServiceB.class));
ServiceA.this.bindService(new Intent(ServiceA.this,ServiceB.class),mServiceConnection, Context.BIND_IMPORTANT);
}
}
}服务B：
public class ServiceB extends Service {
private static final String TAG = ServiceB.class.getSimpleName();
private PendingIntent mPendingIntent;
private MyBinder mBinder;
private MyServiceConnection mServiceConnection;
@Override
public IBinder onBind(Intent intent) {
return mBinder;
}
@Override
public void onCreate() {
super.onCreate();
if (mBinder == null) {
mBinder = new MyBinder();
}
mServiceConnection = new MyServiceConnection();
}
@Override
public int onStartCommand(Intent intent, int flags, int startId) {
this.bindService(new Intent(ServiceB.this, ServiceA.class), mServiceConnection, Context.BIND_IMPORTANT);
mPendingIntent = PendingIntent.getService(this, 0, intent, 0);
Notification.Builder builder = new Notification.Builder(this);
builder.setTicker("守护服务B启动中")
.setContentText("我是来守护服务A的")
.setContentTitle("守护服务B")
.setSmallIcon(R.mipmap.ic_launcher)
.setContentIntent(mPendingIntent)
.setWhen(System.currentTimeMillis());
Notification notification = builder.build();
startForeground(startId, notification);
return START_STICKY;
}
public class MyBinder extends IBridgeInterface.Stub {
@Override
public String getName() throws RemoteException {
return "name:"+TAG;
}
}
class MyServiceConnection implements ServiceConnection {
@Override
public void onServiceConnected(ComponentName componentName, IBinder iBinder) {
String name=null;
try {
name=IBridgeInterface.Stub.asInterface(iBinder).getName();
} catch (RemoteException e) {
e.printStackTrace();
}
Toast.makeText(ServiceB.this, name + "连接成功", Toast.LENGTH_SHORT).show();
}
@Override
public void onServiceDisconnected(ComponentName componentName) {
Toast.makeText(ServiceB.this, TAG + "断开连接", Toast.LENGTH_SHORT).show();
ServiceB.this.startService(new Intent(ServiceB.this, ServiceA.class));
ServiceB.this.bindService(new Intent(ServiceB.this, ServiceA.class), mServiceConnection, Context.BIND_IMPORTANT);
}
}
}IBridgeInterface.aidl
interface IBridgeInterface {
String getName();
}界面：
public class MainActivity extends Activity {
@Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
startService(new Intent(this, ServiceA.class));
startService(new Intent(this, ServiceB.class));
}
}AndroidManifest.xml
<service android:name=".services.ServiceA" />
<service
android:name=".services.ServiceB"
android:process=":remote" />
由于涉及到跨进程，onServiceConnected() 方法中使用
IBridgeInterface.Stub.asInterface(iBinder).getName();
而不能直接类型转换
((ServiceA.MyBinder)iBinder).getName();
onStartCommand
onStartCommand() 方法必须返回整型数。整型数是一个值，用于描述系统应该如何在服务终止的情况下继续运行服务。
返回的值必须是以下常量之一：
START_NOT_STICKY
如果系统在 onStartCommand() 返回后终止服务，则除非有挂起 Intent 要传递，否则系统不会重建服务。
START_STICKY
如果系统在 onStartCommand() 返回后终止服务，则会重建服务并调用 onStartCommand()，但绝对不会重新传递最后一个 Intent。相反，除非有挂起 Intent 要启动服务（在这种情况下，将传递这些 Intent ），否则系统会通过空 Intent 调用 onStartCommand()。这适用于不执行命令、但无限期运行并等待作业的媒体播放器（或类似服务）。
START_REDELIVER_INTENT
如果系统在 onStartCommand() 返回后终止服务，则会重建服务，并通过传递给服务的最后一个 Intent 调用 onStartCommand()。任何挂起 Intent 均依次传递。这适用于主动执行应该立即恢复的作业（例如下载文件）的服务。