ient. To receive the IBinder, the client must create an instance of ServiceConnection and pass it to bindService(). The ServiceConnection includes a callback method that the system calls to deliver the IBinder.
Managing the Lifecycle of a Bound Service
When a service is unbound from all clients, the Android system destroys it (unless it was also started with onStartCommand()). As such, you don't have to manage the lifecycle of your service if it's purely a bound service—the Android system manages it for you based on whether it is bound to any clients.
However, if you choose to implement the onStartCommand() callback method, then you must explicitly stop the service, because the service is now considered to be started. In this case, the service runs until the service stops itself with stopSelf() or another component calls stopService(), regardless of whether it is bound to any clients.
Additionally, if your service is started and accepts binding, then when the system calls your onUnbind()method, you can optionally return true if you would like to receive a call to onRebind() the next time a client binds to the service (instead of receiving a call to onBind()). onRebind() returns void, but the client still receives the IBinder in its onServiceConnected() callback. Below, figure 1 illustrates the logic for this kind of lifecycle.
（三） 使用AIDL (1.不需要IPC：implement a Binder; 2.需要IPC,不需要并发：use a Messenger; 3.需要IPC,需要并发：AIDL) Using AIDL is necessary only if you allow clients from different applications to access your service for IPC and want to handle multithreading in your service. If you do not need to perform concurrent IPC across different applications, you should create your interface by implementing a Binder or, if you want to perform IPC, but do not need to handle multithreading, implement your interface using a Messenger.
- Create the .aidl file
This file defines the programming interface with method signatures.
- Implement the interface
The Android SDK tools generate an interface in the Java programming language, based on your .aidl file. This interface has an inner abstract class named Stub that extends Binder and implements methods from your AIDL interface. You must extend the Stub class and implement the methods.
- Expose the interface to clients
Implement a Service and override onBind() to return your implementation of the Stub class.
IRemoteService.aidl文件：
?
// IRemoteService.aidl
package com.example.boundservice;
// Declare any non-default types here with import statements
/** Example service interface */
interface IRemoteService {
/** Request the process ID of this service, to do evil things with it. */
int getPid();
/** Demonstrates some basic types that you can use as parameters
* and return values in AIDL.
*/
void basicTypes(int anInt, long aLong, boolean aBoolean, float aFloat,
double aDouble, String aString);
}
自动生成(eclipse自动，studio需要rebuild)的IRemoteService.java: ?
?
/*
* This file is auto-generated. DO NOT MODIFY.
* Original file: /Users/Francis/Documents/workspace/BoundService/src/com/example/boundservice/IRemoteService.aidl
*/
package com.example.boundservice;
// Declare any non-default types here with import statements
/** Example service interface */
public interface IRemoteService extends android.os.IInterface
{
/** Local-side IPC implementation stub class. */
public static abstract class Stub extends android.os.Binder implements com.example.boundservice.IRemoteService
{
private static final java.