部分唤醒锁不能用于安装

Question

I'am gathering accelerometer data in my watchface and as soon as the device enter ambient mode the cpu is put to sleep.

I've tried adding a partial_wakelock on creation but it still does not work, A Full wakelock works fine but i want the benefits of having ambient mode such as burn in protection to work.

Any idea whats wrong?

        powerManager = (PowerManager) getSystemService(POWER_SERVICE);
        //wl = powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, "awake");

        wl = powerManager.newWakeLock((PowerManager.SCREEN_BRIGHT_WAKE_LOCK | PowerManager.FULL_WAKE_LOCK | PowerManager.ACQUIRE_CAUSES_WAKEUP), "MyWakelockTag");

The commented line does not work.

I aquire the wakelock in registration of the accelerometer and release it onDestroy.

It is a very frustrating problem and i can not find out what iam doing wrong.

Answer 1

In breif it is normal. Relax.

For battery saving reason some Android devices go to sleep and disable bluetooth mode . To become it active i have just found that only FULL_WAKE_LOCK works. May be, i'm bot right but this is my experince. The other options that helps to save battery must be disabled inside Android OS preference too.

Answer 2

Based from the documentation , you can obtain an instance of PowerManager class by calling Context.getSystemService() .

You may want to try using this:

PowerManager pm = (PowerManager) getSystemService(Context.POWER_SERVICE);

instead of

powerManager = (PowerManager) getSystemService(POWER_SERVICE);

In addition to that, you cannot use ACQUIRE_CAUSES_WAKEUP and ON_AFTER_RELEASE with PARTIAL_WAKE_LOCK .

Please also note that any application using a WakeLock must request the android.permission.WAKE_LOCK permission in an <uses-permission> element of the application's manifest.