一，在frameworks/base/core/java/android/content/Context.java中添加
public static final String RADIO_SERVICE = "radioservice"（自己定义的）；
二，在frameworks/base/core/java/com/auto/radioservice文件中添加IRadioPlayer.aidl
三，在framework/base/Android.mk中添加LOCAL_SRC_FILES中添加一行
core/java/com/auto/radioservice/IRadioPlay.aidl
四，在framework/base/services/java/com/auto中添加自己的服务
比喻 新建文件radioservice，在文件下RadioService.java.
并继承aidl生成的文件 public class RadioService extends IRadioPlayer.Stub
五，在framework/base/services/java/com/android/server/SystemServer.java中添加
RadioService radioService = null;
private void registerHCNService(Context context){
Slog.i(TAG, "RadioService");
radioService = RadioService.getInstance();
if(!radioService.init()){
Slog.e(TAG, "RadioService init failed");
}
ServiceManager.addService(Context.RADIO_SERVICE, radioService);
}
在startOtherServices（）{
.
.
.
registerHCNService(context);
}
六，在/home/mxy/code/v1/frameworks/base/core/java/com/autohcn/auto中创建IRadioManager，RadioManager
用于管理RadioService
说明：本次说的系统服务，是指捆绑在system_process进程中的服务。
仔细阅读源码可以发现，在frameworks/base/services/java/com/android/server/SystemServer.java中添加了很多服务，什么熵信息、电量、wife等等服务，这些服务启动都在launcher之前，一般要继承Binder或者继承一个AIDL。下面试着来添加一个简单系统服务
一。在frameworks/base/core/java/android/os/ 增加一个aidl文件，最后用aidl工具生产一个Java文件，这样可以方便后面：
- package android.os;
- /**
- * Interface that allows controlling and querying YtTts connectivity.
- *
- * {@hide}
- */
- interface IYtTtsService{
- /**
- * 播放Text文字
- */
- int speak(String text);
- }
然后在修改/frameworks/base/Android.mk，在LOCAL_SRC_FILES里添加一行：core/java/android/os/IYtTtsService.aidl \
不确定补充：把AIDL文件写在这个地方似乎可以避免加@hide
二 。在frameworks/base/services/java/com/android/server/ 新建要增加的service，继承上面aidl生产的java：
- package com.android.server;
- import android.content.Context;
- import android.os.IYtTtsService;
- import android.os.RemoteException;
- import android.util.Log;
- public class YtTtsService extends IYtTtsService.Stub {
- private WorkerThread mWorker;
- public YtTtsService(Context context) {
- super();
- mWorker = new WorkerThread("YtTtsServiceWorker");
- mWorker.start();
- Log.i("[YT]", "In YtTtsService-->"+context);
- }
- @Override
- public int speak(String text) throws RemoteException {
- Log.i("[YT]", "In YtTtsService-->"+text);
- return 0;
- }
- private class WorkerThread extends Thread{
- int i = 0;
- public WorkerThread(String name) {
- super(name);
- }
- public void run() {
- while(true){
- i++;
- Log.i("[YT]", "In YtTtsService-->WorkerThread running "+i);
- try {
- Thread.sleep(3000);
- } catch (InterruptedException e) {
- e.printStackTrace();
- }
- }
- }
- }
- }
三。在frameworks/base/services/java/com/android/server/SystemServer.java, ServerThread中run()方法中增加代码：
- try {
- Log.i("[YT]", "In SystemServer, YtTts add..");
- ServiceManager.addService("yttts", new YtTtsService(context));
- } catch (Throwable e) {
- Log.i("[YT]", "In SystemServer, YtTts add err..");
- }
5.在/frameworks/base/core/java/cn/youngtone/tts建一个YtTtsManager类,用于管理YtTtsService：
- package cn.youngtone.tts;
- import android.content.Context;
- import android.os.IYtTtsService;
- import android.os.RemoteException;
- import android.util.Log;
- public class YtTtsManager {
- IYtTtsService service;
- public YtTtsManager(Context context ,IYtTtsService service) {
- this.service = service;
- }
- public void speak(String text) {
- try {
- Log.e("[YT]" , "In YtTtsManage-->speak():"+text);
- service.speak(text);
- } catch (RemoteException e) {
- Log.e("[YT]" , "In YtTtsManage-->E:RemoteException");
- e.printStackTrace();
- }
- }
- }
四。 在ContextImpl getSystemService中添加代码：
- if ("yttts".equals(name)) {
- if (mYtTtsManager == null) {
- IBinder b = ServiceManager.getService("yttts");
- IYtTtsService service = IYtTtsService.Stub.asInterface(b);
- mYtTtsManager = new YtTtsManager(this, service);
- }
- return mYtTtsManager;
- }
五。测试代码
- YtTtsManager mManager = (YtTtsManager)getSystemService("yttts");
- mManager.speak("这是一个简单的系统服务!");
END.
参考：http://blog.csdn.net/aiai373824745/article/details/7439896