安卓添加系统自定义服务

安卓版本：4.4
因为项目中用到了，做一下简要笔记。

定义aidl文件，如IFlyscaleManager.aidl，放到frameworks/base/core/java/android/flyscale/IFlyscaleManager.aidl
定义服务FlyscaleService.java,实现该IFlyscaleManager.aidl,放到frameworks/base/service/java/com/android/server/flyscale/FlyscaleService.java
调用FlyscaleService服务，定义FlyscaleManager.java，放到frameworks/base/core/java/android/flyscael/FlyscaleManager.java
添加服务，修改frameworks/base/core/java/android/content/Context.java
添加：

/**
 *@author bianjb add flyscale service
 */
public static final String FLYSCALE_SERVICE = "flyscale";

修改initAndLoop()方法，添加

//framework/base/services/java/com/android/server/SystemServer.java 
//bianjb:add flyscale service
FlyscaleService flyscaleService = null;

//bianjb: add for flyscale service
try {
    if (PowerGuruService.isEnabled()) {
        Slog.i(TAG, "Flyscale Manager");
        flyscaleService = new FlyscaleService(context);
        ServiceManager.addService(Context.FLYSCALE_SERVICE, flyscaleService);
    }
} catch (Throwable e) {
    Slog.e(TAG, "Failure FlyscaleService", e);
}

实例化并注册服务
修改frameworks/base/core/java/android/app/ContextImpl.java
的static代码块中添加

//bianjb:add for flyscale service
registerService(FLYSCALE_SERVICE, new ServiceFetcher() {
public Object createService(ContextImpl ctx) {
    IBinder b = ServiceManager.getService(FLYSCALE_SERVICE);
    IFlyscaleManager service = IFlyscaleManager.Stub.asInterface(b);
    return new FlyscaleManager(ctx, service);
}});

编译IFlyscaleService.aidl
修改frameworks/base/Android.mk
添加

#add for flyscale service
LOCAL_SRC_FILES += core/java/android/flyscale/IFlyscaleManager.aidl \

之后重新编译即可，在APP调用的方法与调用ActivityManager方法一致。