Android中不使用AIDL实现Service的远程调用

优点:Client端与Server端的DESCRIPTOR可以自定义,不受包名限制


实质中其实是使用底层Binder机制提供的Java层接口 Binder 、IInterface等去实现

客户端中使用transact发起进程间通信请求,服务端会回调onTransact来处理请求


Common Interface:

public interface ITimeCountService {
	int getCount() throws RemoteException;
} 


Server:

public abstract class TimeCountStub extends android.os.Binder implements
		IInterface, ITimeCountService {
	private static final java.lang.String DESCRIPTOR = "com.example.servicedemo.nonaidl.ITimeCountService";

	/** Construct the stub at attach it to the interface. */
	public TimeCountStub() {
		this.attachInterface(this, DESCRIPTOR);
	}

	@Override
	public android.os.IBinder asBinder() {
		return this;
	}

	@Override
	public boolean onTransact(int code, android.os.Parcel data,
			android.os.Parcel reply, int flags)
			throws android.os.RemoteException {
		switch (code) {
		case INTERFACE_TRANSACTION: {
			reply.writeString(DESCRIPTOR);
			return true;
		}
		case TRANSACTION_getCount: {
			data.enforceInterface(DESCRIPTOR);
			int _result = this.getCount();
			reply.writeNoException();
			reply.writeInt(_result);
			return true;
		}
		}
		return super.onTransact(code, data, reply, flags);
	}

	static final int TRANSACTION_getCount = (android.os.IBinder.FIRST_CALL_TRANSACTION + 0);
}


Client:

public class TimeCountProxy implements /*IInterface,*/ ITimeCountService {
	private static final java.lang.String DESCRIPTOR = "com.example.servicedemo.nonaidl.ITimeCountService";
	private android.os.IBinder mRemote;

	TimeCountProxy(android.os.IBinder remote) {
		mRemote = remote;
	}

//	@Override
//	public android.os.IBinder asBinder() {
//		return mRemote;
//	}

	public java.lang.String getInterfaceDescriptor() {
		return DESCRIPTOR;
	}
	
	/**
	 * Cast an IBinder object into an
	 * com.example.servicedemo.nonaidl.ITimeCountService interface, generating a
	 * proxy if needed.
	 */
	public static ITimeCountService asInterface(
			android.os.IBinder obj) {
		if ((obj == null)) {
			return null;
		}
		android.os.IInterface iin = obj.queryLocalInterface(DESCRIPTOR);
		if (((iin != null) && (iin instanceof ITimeCountService))) {
			return ((ITimeCountService) iin);
		}
		return new TimeCountProxy(obj);
	}

	@Override
	public int getCount() throws android.os.RemoteException {
		android.os.Parcel _data = android.os.Parcel.obtain();
		android.os.Parcel _reply = android.os.Parcel.obtain();
		int _result;
		try {
			_data.writeInterfaceToken(DESCRIPTOR);
			mRemote.transact(TimeCountStub.TRANSACTION_getCount, _data, _reply,
					0);
			_reply.readException();
			_result = _reply.readInt();
		} finally {
			_reply.recycle();
			_data.recycle();
		}
		return _result;
	}
}


Service中片段:

public class TimeCountService extends Service {

	...

	TimeCountStub stub = new TimeCountStub() {

		@Override
		public int getCount() throws RemoteException {
			return count;
		}		
	};

	@Override
	public IBinder onBind(Intent intent) {
		Log.i(TAG, "onBind");
		return stub;
	}
	
	...
	
}


Client中片段:

public class MainActivity extends Activity {
	
	...
	
	private ITimeCountService timeCountService;

	private ServiceConnection conn = new ServiceConnection() {
		
		@Override
		public void onServiceConnected(ComponentName name, IBinder service) {
			Log.i(TAG, "onServiceConnected");
			timeCountService = TimeCountProxy.asInterface(service);
			
			
			Log.i(TAG, "timeCountService: " + timeCountService);
			
			canTimeUpdateTaskRunning = true;
			TimeUpateTask t = new TimeUpateTask();
			t.execute(new Object());
			
			
			Log.i(TAG, "task status: " + t.getStatus());
		}
		
		@Override
		public void onServiceDisconnected(ComponentName name) {
			Log.i(TAG, "onServiceDisconnected");
		}
	};
	
	...

}


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