aidl 中通过RemoteCallbackList 运用到的回调机制： service回调activity的方法

说明：我没有写实例代码，直接拿项目中的代码，有点懒了，这里我省略贴出两个aidl文件。

  TtsService extends Service

private final RemoteCallbackList<ITtsCallback> mCallbacks
= new RemoteCallbackList<ITtsCallback>();

private final android.speech.tts.ITts.Stub mBinder = new Stub() {

public int registerCallback(String packageName, ITtsCallback cb) {
if (cb != null) {
mCallbacks.register(cb);
mCallbacksMap.put(packageName, cb);
return TextToSpeech.SUCCESS;
}
return TextToSpeech.ERROR;
}

public int unregisterCallback(String packageName, ITtsCallback cb) {
if (cb != null) {
mCallbacksMap.remove(packageName);
mCallbacks.unregister(cb);
return TextToSpeech.SUCCESS;
}
return TextToSpeech.ERROR;
}

public int speak(String callingApp, String text, int queueMode, String[] params) {
ArrayList<String> speakingParams = new ArrayList<String>();
if (params != null) {
speakingParams = new ArrayList<String>(Arrays.asList(params));
}
return this.speak(callingApp, text, queueMode, speakingParams);
}

private void dispatchProcessingCompletedCallback(String packageName) {
ITtsCallback cb = mCallbacksMap.get(packageName);
if (cb == null){
return;
}
//Log.i("TtsService", "TTS callback: dispatch started");
// Broadcast to all clients the new value.
final int N = mCallbacks.beginBroadcast();
try {
cb.processingCompleted();
} catch (RemoteException e) {
// The RemoteCallbackList will take care of removing
// the dead object for us.
}
mCallbacks.finishBroadcast();
//Log.i("TtsService", "TTS callback: dispatch completed to " + N);
}

@Override
public void onDestroy() {
super.onDestroy();

// TODO replace the call to stopAll() with a method to clear absolutely all upcoming
// uses of the native synth, including synthesis to a file, and delete files for which
// synthesis was not complete.
stopAll();

// Unregister all callbacks.
mCallbacks.kill();
}

在activity中

mITtscallback = new ITtsCallback.Stub() {
public void processingCompleted() throws RemoteException {
if (listener != null) {
listener.onProcessingCompleted();
}
}
};

result = mITts.registerCallback(mPackageName, mITtscallback);

上面只是一个贴代码没有做任何说明，基本的意思我想大家也能通过代码来看懂。

// int N = mCallbacks.beginBroadcast();
// try {
// for (int i = 0; i < N; i++) {
// mCallbacks.getBroadcastItem(i).showResult(mSlot);
// }
// } catch (RemoteException e) {
// Log("" + e);
// }
// mCallbacks.finishBroadcast();

-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------

上传一个写的工作中用到的demo

package com.pateo.aidl;

interface ICallback {

void showResult(String result);

}

package com.pateo.aidl;
import com.pateo.aidl.ICallback;

interface IMyService {

void init(String packageName,String slot);
void registerCallback(String packageName,ICallback cb);
void unregisterCallback(String packageName,ICallback cb);

}

package com.pateo.service;

import java.util.HashMap;

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 com.pateo.aidl.ICallback;
import com.pateo.aidl.IMyService;

public class VuiService extends Service {

private RemoteCallbackList<ICallback> mCallbacks = new RemoteCallbackList<ICallback>();
private HashMap<String, ICallback> mCallbacksMap = new HashMap<String, ICallback>();
private String mSlot = "";
private String mPackageName = "";

@Override
public void onStart(Intent intent, int startId) {
super.onStart(intent, startId);
}

@Override
public IBinder onBind(Intent intent) {
return remoteBinder;
}

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

@Override
public boolean onUnbind(Intent intent) {
return super.onUnbind(intent);
}

public void onRebind(Intent intent) {
super.onRebind(intent);
}

private IMyService.Stub remoteBinder = new IMyService.Stub() {

@Override
public void init(String packageName,String slot) throws RemoteException {
mSlot = slot;
mPackageName = packageName;

//Ä£Ä⿪ʌÆô¶¯Ê¶±ð£¬ÕâÀïµÄ4000ºÁÃëÏ൱ÓÚžøÓèµÄʶ±ð¹ý³ÌµÄʱŒä£¬Õâžö¿ÉÒÔÔÚʶ±ðœá¹ûÀïÃæÈ¥µ÷ÓÃ
mHandler.sendEmptyMessageDelayed(0, 4000);
}

@Override
public void unregisterCallback(String packageName, ICallback cb) {
if (cb != null) {
mCallbacks.unregister(cb);
mCallbacksMap.remove(packageName);
}
}

//°üÃû×¢²áµÄ·œÊœ£¬ÕâÑùŸÍ±ÜÃâÁ˺ܶàÓŠÓÃ×¢²á¶ŒÈ¥»Øµ÷£¬ÕâÀïÍš¹ýÓŠÓÞøÓèµÄpackageNameÀŽÆ¥ÅäŸßÌå»Øµ÷ÄÄÒ»žöÓŠÓõÄcallback
@Override
public void registerCallback(String packageName, ICallback cb) {
if (cb != null) {
mCallbacks.register(cb);
mCallbacksMap.put(packageName, cb);
}
}
};

//ÕâÀïÍš¹ýÓŠÓÞøÓèµÄpackageNameÀŽÆ¥ÅäŸßÌå»Øµ÷ÄÄÒ»žöÓŠÓõÄcallback
private void dispatchProcessingCompletedCallback() {
ICallback cb = mCallbacksMap.get(mPackageName);
if (cb == null){
return;
}
final int N = mCallbacks.beginBroadcast();
try {
cb.showResult(mSlot);
} catch (RemoteException e) {
}
mCallbacks.finishBroadcast();
}

private Handler mHandler = new Handler() {
@Override
public void handleMessage(Message msg) {
dispatchProcessingCompletedCallback();
super.handleMessage(msg);
}
};
}

package com.pateo;

import com.pateo.service.VuiService;
import com.pateo.aidl.ICallback;
import com.pateo.aidl.IMyService;
import com.pateo.R;

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.Handler;
import android.os.IBinder;
import android.os.Message;
import android.os.RemoteException;
import android.view.View;
import android.view.View.OnClickListener;
import android.widget.Button;
import android.widget.TextView;

public class AppActivity extends Activity {

TextView tv;
IMyService myservice ;
String mResult ;

@Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.main);
tv = (TextView) findViewById(R.id.tv);

//Ä£Äâ°ŽmodeŒü
Button btn =  (Button) findViewById(R.id.startBtn);
btn.setOnClickListener(new OnClickListener() {
@Override
public void onClick(View v) {
Intent intent = new Intent(AppActivity.this,VuiService.class);
bindService(intent, serviceConnection, Context.BIND_AUTO_CREATE);
}
});
}

private ServiceConnection serviceConnection = new ServiceConnection() {

@Override
public void onServiceDisconnected(ComponentName name) {
myservice = null;
}

@Override
public void onServiceConnected(ComponentName name, IBinder service) {
myservice = IMyService.Stub.asInterface(service);
try {
if(myservice != null){
myservice.registerCallback("com.pateo",mCallback);
myservice.init("com.pateo","ÖØÌý|»ØžŽ");//ΪÁËÓïÒô¿òŒÜœÓÊÕµœÕâЩŽÊºó°ÑÕâÁœžöŽÊ²åÈë²å²Û£¬ÕâÑùŸÍ¿ÉÒÔ·¶Î§Ð¡Ìážßʶ±ð
//ÕâÀﻹ¿ÉÒÔ×ö°ÑÒ»Œ¶ŽÊÌõÒ²·¢¹ýÈ¥£¬²åÈë²å²Û¡£
}
} catch (RemoteException e) {
}
}
};

/**
* serviceµÄ»Øµ÷·œ·š
*/
private ICallback.Stub mCallback = new ICallback.Stub() {

//µÈŽýʶ±ðœá¹ûÈ»ºóshow³öÀŽ
@Override
public void showResult(String result) {
try {
mResult = result;
Message msgget = Message.obtain();
msgget.what = 1;
mHandler.sendMessage(msgget);
} catch (Exception e) {
}
}
};

private Handler mHandler = new Handler() {

@Override
public void handleMessage(Message msg) {
super.handleMessage(msg);
switch (msg.what) {
case 1:
tv.setText("result : " + mResult);
break;
}
}
};

@Override
protected void onDestroy() {
unbindService(serviceConnection);
super.onDestroy();
}

}