Android Doze mode - 小破孩的博客

大部分内容来自于 http://blog.csdn.net/gaugamela/article/details/52981984

代码基本上都在 /frameworks/base/services/core/java/com/android/server/DeviceIdleController.java

DeviceIdleController 作为一个系统级服务在开机时由 SystemServer 初始化启动

    private void startOtherServices() {
                ......
                mSystemServiceManager.startService(DeviceIdleController.class);    

开机过程中依次调用到 DeviceIdleController 的构造函数 -> onStart -> onBootPhase

构造函数

    public DeviceIdleController(Context context) {
        super(context);
        // 路径是 /data/system/deviceidle.xml, 用于定义idle模式也能正常工作的非系统应用
        mConfigFile = new AtomicFile(new File(getSystemDir(), "deviceidle.xml"));
        mHandler = new MyHandler(BackgroundThread.getHandler().getLooper());
    }

onStart

public void onStart() {
    final PackageManager pm = getContext().getPackageManager();

    synchronized (this) {
        //读取配置文件，判断Doze模式是否允许被开启, 这里会有区分 light 和 deep
        mLightEnabled = mDeepEnabled = getContext().getResources().getBoolean(
                com.android.internal.R.bool.config_enableAutoPowerModes);

        //分析PKMS时提到过，PKMS扫描系统目录的xml，将形成SystemConfig
        SystemConfig sysConfig = SystemConfig.getInstance();

        //获取除了device Idle模式外，都可以运行的系统应用白名单
        ArraySet<String> allowPowerExceptIdle = sysConfig.getAllowInPowerSaveExceptIdle();
        for (int i=0; i<allowPowerExceptIdle.size(); i++) {
            String pkg = allowPowerExceptIdle.valueAt(i);
            try {
                ApplicationInfo ai = pm.getApplicationInfo(pkg,
                        PackageManager.MATCH_SYSTEM_ONLY);
                int appid = UserHandle.getAppId(ai.uid);
                mPowerSaveWhitelistAppsExceptIdle.put(ai.packageName, appid);
                mPowerSaveWhitelistSystemAppIdsExceptIdle.put(appid, true);
            } catch (PackageManager.NameNotFoundException e) {
            }
        }

        //获取device Idle模式下，也可以运行的系统应用白名单
        ArraySet<String> allowPower = sysConfig.getAllowInPowerSave();
        for (int i=0; i<allowPower.size(); i++) {
             String pkg = allowPower.valueAt(i);
            try {
                ApplicationInfo ai = pm.getApplicationInfo(pkg,
                         PackageManager.MATCH_SYSTEM_ONLY);
                int appid = UserHandle.getAppId(ai.uid);
                // These apps are on both the whitelist-except-idle as well
                // as the full whitelist, so they apply in all cases.
                mPowerSaveWhitelistAppsExceptIdle.put(ai.packageName, appid);
                mPowerSaveWhitelistSystemAppIdsExceptIdle.put(appid, true);
                mPowerSaveWhitelistApps.put(ai.packageName, appid);
                mPowerSaveWhitelistSystemAppIds.put(appid, true);
            } catch (PackageManager.NameNotFoundException e) {
            }
        }

        //Constants为deviceIdleController中的内部类，继承ContentObserver
        //监控数据库变化，同时得到Doze模式定义的一些时间间隔
        mConstants = new Constants(mHandler, getContext().getContentResolver());

        //解析deviceidle.xml，并将其中定义的package对应的app，加入到mPowerSaveWhitelistUserApps中
        readConfigFileLocked();

        //将白名单的内容给AlarmManagerService和PowerMangerService
        //例如：DeviceIdleController判断开启Doze模式时，会通知PMS
        //此时除去白名单对应的应用外，PMS会将其它所有的WakeLock设置为Disable状态
        updateWhitelistAppIdsLocked();

        //以下的初始化，都是假设目前处在进入Doze模式相反的条件上
        mNetworkConnected = true;
        mScreenOn = true;
        // 先假设正在充电，如果不是则在电量变化时可以获取到真实的状态
        mCharging = true;

        //Doze模式定义终端初始时为ACTIVE状态
        mState = STATE_ACTIVE;
        //屏幕状态初始时为ACTIVE状态
        mLightState = LIGHT_STATE_ACTIVE;
        mInactiveTimeout = mConstants.INACTIVE_TIMEOUT;
    }

    //发布服务
    //BinderService和LocalService均为DeviceIdleController的内部类
    mBinderService = new BinderService();
    publishBinderService(Context.DEVICE_IDLE_CONTROLLER, mBinderService);
    publishLocalService(LocalService.class, new LocalService());
}

构造函数

onStart

onBootPhase

CATALOG