Android 休眠与唤醒的实现源码分析

Posted 2021-07-16 王睿丶

文章目录

• • 1、代码实现
  • • 1.1、休眠
    • 1.2、唤醒
  • 2、源码分析
  • • 2.1、休眠
    • 2.2、唤醒
  • 3、开发时坑点

1、代码实现

🔺说明：

应用层：

 android:sharedUserId="android.uid.system"	除了声明系统权限，还需要系统签名APK

    <uses-permission android:name="android.permission.WAKE_LOCK" />		
    <uses-permission android:name="android.permission.DEVICE_POWER" />
    <uses-permission android:name="android.permission.DISABLE_KEYGUARD" />

框架层：因为PowerManagerl类的reboot()、shutdown不对外公开，所以我们在Android Framework层进行实现！

通过JNI技术让上层代码与底层代码产生联系，就可以实现休眠与唤醒！

1.1、休眠

public static void sleep(Context context) {
        IPowerManager mPowerManager = IPowerManager.Stub.asInterface(ServiceManager.getService("power"));
        try{
            mPowerManager.goToSleep(SystemClock.uptimeMillis()+1,0,0);
        }catch (Exception e){
            Log.d("SleepAndWakeLockControl","休眠失败");
        }
    }

1.2、唤醒

public static void wake(Context context){
        IPowerManager mPowerManager = IPowerManager.Stub.asInterface(ServiceManager.getService("power"));
        try {
            mPowerManager.wakeUp(SystemClock.uptimeMillis()+1,0,"wakeUp",context.getOpPackageName());
        }catch (Exception e){
            Log.d("SleepAndWakeLockControl","唤醒失败");
        }
    }

2、源码分析

2.1、休眠

    /**
     * Forces the device to go to sleep.
     * <p>
     * Overrides all the wake locks that are held.
     * This is what happens when the power key is pressed to turn off the screen.
     * </p><p>
     * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
     * </p>
     *
     * @param time The time when the request to go to sleep was issued, in the
     * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
     * order the go to sleep request with other power management functions.  It should be set
     * to the timestamp of the input event that caused the request to go to sleep.
     * @param reason The reason the device is going to sleep.
     * @param flags Optional flags to apply when going to sleep.
     *
     * @see #userActivity
     * @see #wakeUp
     *
     * @hide Requires signature permission.
     */
    @UnsupportedAppUsage
    public void goToSleep(long time, int reason, int flags) {
        try {
            mService.goToSleep(time, reason, flags);
        } catch (RemoteException e) {
            throw e.rethrowFromSystemServer();
        }
    }

2.2、唤醒

 /**
     * Forces the device to wake up from sleep.
     * <p>
     * If the device is currently asleep, wakes it up, otherwise does nothing.
     * This is what happens when the power key is pressed to turn on the screen.
     * </p><p>
     * Requires the {@link android.Manifest.permission#DEVICE_POWER} permission.
     * </p>
     *
     * @param time The time when the request to wake up was issued, in the
     * {@link SystemClock#uptimeMillis()} time base.  This timestamp is used to correctly
     * order the wake up request with other power management functions.  It should be set
     * to the timestamp of the input event that caused the request to wake up.
     *
     * @param reason The reason for the wake up.
     *
     * @param details A free form string to explain the specific details behind the wake up for
     *                debugging purposes.
     *
     * @see #userActivity
     * @see #goToSleep
     * @hide
     */
    public void wakeUp(long time, @WakeReason int reason, String details) {
        try {
            mService.wakeUp(time, reason, details, mContext.getOpPackageName());
        } catch (RemoteException e) {
            throw e.rethrowFromSystemServer();
        }
    }

3、开发时坑点

1、需要系统签名的APK，大家应该都知道，我主要讲第二个

2、无论是toSleep()、wakeUp()它的time参数都要用：
SystemClock.uptimeMillis()+几都行
SystemClock.uptimeMillis()参数主要表示：从开机到现在的毫秒数（手机睡眠的时间不包括在内）；

如果不使用这个参数，直接填1*1000或者其他则功能只能使用一次，第二次就会失灵。