使用android中的AIDL让Service与Activity互相通信(service回调activity)

首先建立一个ICallback.aidl文件,作为Activity中的回调方法

 package com.zhang.test.service;

      interface ICallback {
      void showResult(int result);
      }

然后再建立一个IService.aidl用来在Activity中接收Service回调,以及在Service中onBind时返回的Binder
注意:aidl中import不能写com.xxx.*,要写全类的路径

 package com.zhang.test.service;

      import com.zhang.test.service.ICallback;

      interface IService {
              void registerCallback(ICallback cb);
              void unregisterCallback(ICallback cb);
      }

接下来是service:
MainService.java

 package com.zhang.test.service;

       import android.app.Service;
       import android.content.Intent;
       import android.os.Handler;
       import android.os.IBinder;
       import android.os.Message;
       import android.os.RemoteCallbackList;
       import android.os.RemoteException;
      import android.util.Log;

      public class MainService extends Service {

          private static final String TAG = "MainService";

          private RemoteCallbackList<icallback> mCallbacks = new RemoteCallbackList<icallback>();

          private IService.Stub mBinder = new IService.Stub() {

              @Override
              public void unregisterCallback(ICallback cb){
                  if(cb != null) {
                      mCallbacks.unregister(cb);
                 }
              }

              @Override
              public void registerCallback(ICallback cb){
                  if(cb != null) {
                      mCallbacks.register(cb);
                  }
              }
          };

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

          @Override
          public void onCreate() {
              Log.d(TAG, "onCreate");
              //这里不知道为什么,直接使用callback方法回调showResult
              //mCallbacks.beginBroadcast()是0,需要用handler延迟1000毫秒
              //也许是在activity中binService太耗时的原因?
               mHandler.sendEmptyMessageDelayed(0, 1000);
              super.onCreate();
          }

          @Override
          public void onDestroy() {
              mHandler.removeMessages(0);
              mCallbacks.kill();
              super.onDestroy();
          }

          private void callBack() {
              int N = mCallbacks.beginBroadcast();
              try {
                  for (int i = 0; i < N; i++) {
                      mCallbacks.getBroadcastItem(i).showResult(i);
                  }
              } catch (RemoteException e) {
                  Log.e(TAG, "", e);
              }
              mCallbacks.finishBroadcast();
          }

          private Handler mHandler = new Handler() {

              @Override
              public void handleMessage(Message msg) {
                  callBack();
                  super.handleMessage(msg);
             }
          };
      }
      </icallback></icallback>

然后是activity:

 package com.zhang.test;

      import android.app.Activity;
      import android.content.ComponentName;
      import android.content.Context;
      import android.content.Intent;
      import android.content.ServiceConnection;
      import android.os.Bundle;
      import android.os.IBinder;
      import android.os.RemoteException;
      import android.util.Log;

      import com.zhang.test.service.ICallback;
      import com.zhang.test.service.IService;
      import com.zhang.test.service.MainService;

      public class MainActivity extends Activity {

          private static final String TAG = "MainActivity";

          private IService mService;

          /** Called when the activity is first created. */
          @Override
          public void onCreate(Bundle savedInstanceState) {
              super.onCreate(savedInstanceState);
              setContentView(R.layout.main);
              Intent i = new Intent(this, MainService.class);
              bindService(i, mConnection, Context.BIND_AUTO_CREATE);
          }

          @Override
          protected void onDestroy() {
              if(mService!=null){
                 try {
                     mService.unregisterCallback(mCallback);
                  } catch (RemoteException e) {
                      Log.e(TAG, "", e);
                  }
              }
              //destroy的时候不要忘记unbindService
               unbindService(mConnection);
              super.onDestroy();
          }

          /**
           * service的回调方法
           */
          private ICallback.Stub mCallback = new ICallback.Stub() {

              @Override
              public void showResult(int result) {
                  Log.d(TAG, " result : " + result);
              }
          };

          /**
           * 注册connection
           */
          private ServiceConnection mConnection = new ServiceConnection() {

              @Override
              public void onServiceDisconnected(ComponentName name) {
                  Log.d(TAG, "onServiceDisconnected");
                  mService = null;
              }

              @Override
             public void onServiceConnected(ComponentName name, IBinder service) {
                  Log.d(TAG, "onServiceConnected");
                  mService = IService.Stub.asInterface(service);
                  try {
                      mService.registerCallback(mCallback);
                  } catch (RemoteException e) {
                      Log.e(TAG, "", e);
                  }
              }
          };
      }

最后不要忘记在manifest中加上service标记:

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