1） 增加AIDL接口文件

文件：frameworks/base/core/java/android/os/ICpuFreqService.aidl

package android.os;

import android.os.WorkSource;

/** @hide */

interface ICpuFreqService

{

int getCurGovernor();

int getCurFrequency();

}

2） 在Android.mk中增加ICpuFreqService.aidl接口文件的编译选项

文件：frameworks/base/Android.mk

LOCAL_SRC_FILES += \

……….

core/java/android/os/ICpuFreqService.aidl\

……..

3） 实现CpuFreqService.java

文件：frameworks/base/services/java/com/android/server$ ls CpuFreqService.java

package com.android.server;

import android.os.ICpuFreqService;

class CpuFreqService extendsICpuFreqService.Stub{

static int EnterTimes=0;

public int getCurGovernor()

{

return0x11233;

}

public int getCurFrequency()

{

EnterTimes++;

return (EnterTimes*50);

}

}

4） 在SystemService中注册service

文件：frameworks/base/services/java/com/android/server/SystemServer.java

CpuFreqService cpufreq=null;

………………

Slog.i(TAG, "CpuFreq Manager");

cpufreq = new CpuFreqService();

ServiceManager.addService("cpufreq",cpufreq);

5） 在APP中调用AIDL接口

…………….

import android.os.ServiceManager;

import android.os.ICpuFreqService;

……………...

try {

ICpuFreqService cpuFreq=

ICpuFreqService.Stub.asInterface( ServiceManager.getService("cpufreq"));

setSummaryText("baseband_version",Integer.toString(cpuFreq.getCurGovernor()));

Log.e("Status","Governor=" + Integer.toString(cpuFreq.getCurGovernor()));

Log.e("Status","Freq ="+ Integer.toString(cpuFreq.getCurFrequency()));

} catch (Exception e)

{

}