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

在AIDL中让Service调用Activity的方法
代码:
首先建立一个ICallback.aidl文件,作为Activity中的回调方法

 

1     package com.zhang.test.service;
2 
3     interface ICallback {
4     void showResult(int result);
5     }

 

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

 

1     package com.zhang.test.service;
2 
3     import com.zhang.test.service.ICallback;
4 
5     interface IService {
6             void registerCallback(ICallback cb);
7             void unregisterCallback(ICallback cb);
8     }

 

接下来是service:
MainService.java

 

 1     package com.zhang.test.service;
 2 
 3     import android.app.Service;
 4     import android.content.Intent;
 5     import android.os.Handler;
 6     import android.os.IBinder;
 7     import android.os.Message;
 8     import android.os.RemoteCallbackList;
 9     import android.os.RemoteException;
10     import android.util.Log;
11 
12     public class MainService extends Service {
13 
14         private static final String TAG = "MainService";
15 
16         private RemoteCallbackList<icallback> mCallbacks = new RemoteCallbackList<icallback>();
17 
18         private IService.Stub mBinder = new IService.Stub() {
19 
20             @Override
21             public void unregisterCallback(ICallback cb){
22                 if(cb != null) {
23                     mCallbacks.unregister(cb);
24                 }
25             }
26 
27             @Override
28             public void registerCallback(ICallback cb){
29                 if(cb != null) {
30                     mCallbacks.register(cb);
31                 }
32             }
33         };
34 
35         @Override
36         public IBinder onBind(Intent intent) {
37             Log.d(TAG, "onBind");
38             return mBinder;
39         }
40 
41         @Override
42         public void onCreate() {
43             Log.d(TAG, "onCreate");
44             //这里不知道为什么,直接使用callback方法回调showResult
45             //mCallbacks.beginBroadcast()是0,需要用handler延迟1000毫秒
46             //也许是在activity中binService太耗时的原因?
47              mHandler.sendEmptyMessageDelayed(0, 1000);
48             super.onCreate();
49         }
50 
51         @Override
52         public void onDestroy() {
53             mHandler.removeMessages(0);
54             mCallbacks.kill();
55             super.onDestroy();
56         }
57 
58         private void callBack() {
59             int N = mCallbacks.beginBroadcast();
60             try {
61                 for (int i = 0; i < N; i++) {
62                     mCallbacks.getBroadcastItem(i).showResult(i);
63                 }
64             } catch (RemoteException e) {
65                 Log.e(TAG, "", e);
66             }
67             mCallbacks.finishBroadcast();
68         }
69 
70         private Handler mHandler = new Handler() {
71 
72             @Override
73             public void handleMessage(Message msg) {
74                 callBack();
75                 super.handleMessage(msg);
76             }
77         };
78     }
79     </icallback></icallback>

 

然后是activity:

 

 1     package com.zhang.test;
 2 
 3     import android.app.Activity;
 4     import android.content.ComponentName;
 5     import android.content.Context;
 6     import android.content.Intent;
 7     import android.content.ServiceConnection;
 8     import android.os.Bundle;
 9     import android.os.IBinder;
10     import android.os.RemoteException;
11     import android.util.Log;
12 
13     import com.zhang.test.service.ICallback;
14     import com.zhang.test.service.IService;
15     import com.zhang.test.service.MainService;
16 
17     public class MainActivity extends Activity {
18 
19         private static final String TAG = "MainActivity";
20 
21         private IService mService;
22 
23         /** Called when the activity is first created. */
24         @Override
25         public void onCreate(Bundle savedInstanceState) {
26             super.onCreate(savedInstanceState);
27             setContentView(R.layout.main);
28             Intent i = new Intent(this, MainService.class);
29             bindService(i, mConnection, Context.BIND_AUTO_CREATE);
30         }
31 
32         @Override
33         protected void onDestroy() {
34             if(mService!=null){
35                 try {
36                     mService.unregisterCallback(mCallback);
37                 } catch (RemoteException e) {
38                     Log.e(TAG, "", e);
39                 }
40             }
41             //destroy的时候不要忘记unbindService
42              unbindService(mConnection);
43             super.onDestroy();
44         }
45 
46         /**
47          * service的回调方法
48          */
49         private ICallback.Stub mCallback = new ICallback.Stub() {
50 
51             @Override
52             public void showResult(int result) {
53                 Log.d(TAG, " result : " + result);
54             }
55         };
56 
57         /**
58          * 注册connection
59          */
60         private ServiceConnection mConnection = new ServiceConnection() {
61 
62             @Override
63             public void onServiceDisconnected(ComponentName name) {
64                 Log.d(TAG, "onServiceDisconnected");
65                 mService = null;
66             }
67 
68             @Override
69             public void onServiceConnected(ComponentName name, IBinder service) {
70                 Log.d(TAG, "onServiceConnected");
71                 mService = IService.Stub.asInterface(service);
72                 try {
73                     mService.registerCallback(mCallback);
74                 } catch (RemoteException e) {
75                     Log.e(TAG, "", e);
76                 }
77             }
78         };
79     }

 

最后不要忘记在manifest中加上service标记:

 

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

总结:
通过aidl总算实现了Service与Activity的通信,写起来麻烦点,使用诸如ContentProvider,Broadcast等也可以实现.
这样做很像是在使用MVC设计模式(Activity负责View,Service以及其他类负责 Model,aidl(ServiceConnection)负责Controller)