android app设置亮屏的几种方式以及功耗对比
在Android app开发中，为了让某个页面持续显示一定时间，需要设置亮屏代码。
常用的方法有四种，分别如下：
方法1：通过PowerManager获取wakelock。
方法2：在view中设置view.setKeepScreenOn(true);
方法3：设置WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON 和 setTurnScreenOn(true);
方法4：在xml中设置android:keepScreenOn="true"
下面说一下上面四种方法的对比：
方法1一般用在非activity、fragment，无法操作UI界面的服务，如service、receiver。
需要申请权限
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wakeLock = pm.newWakeLock((PowerManager.SCREEN_BRIGHT_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP), "reminder:");
//wakeLock.setReferenceCounted(false);
wakeLock.acquire(6000L);
wakelock.acquire()不带参数的不建议使用，建议使用带参数的，带参数的系统会自动release，是比较安全的，即便是手动release后被系统handler自动释放，也不会出现crash。因为PowerManager有两个计数值，mInternalCount和mExternalCount，系统自动释放时不会操作mExternalCount。
public void release(int flags) {
synchronized (mToken) {
if (mInternalCount > 0) {
// internal count must only be decreased if it is > 0 or state of
// the WakeLock object is broken.
mInternalCount--;
}
if ((flags & RELEASE_FLAG_TIMEOUT) == 0) {
mExternalCount--;
}
if (!mRefCounted || mInternalCount == 0) {
mHandler.removeCallbacks(mReleaser);
if (mHeld) {
Trace.asyncTraceEnd(Trace.TRACE_TAG_POWER, mTraceName, 0);
try {
mService.releaseWakeLock(mToken, flags);
} catch (RemoteException e) {
throw e.rethrowFromSystemServer();
}
mHeld = false;
}
}
if (mRefCounted && mExternalCount < 0) {
throw new RuntimeException("WakeLock under-locked " + mTag);
}
}
}但如果应用层手动执行release比acquire要多，且没有设置mRefCounted为true，系统就会抛异常。
其中wakeLock.setReferenceCounted(false);的作用是无论调用多少次acquire，只要最后执行了一次release就会释放wakelock，该值默认为true；
WakeLock获取时相关的flag如下所示：
PARTIAL_WAKE_LOCK :保持CPU 运转，屏幕和键盘灯有可能是关闭的。
SCREEN_DIM_WAKE_LOCK ：保持CPU 运转，允许保持屏幕显示但有可能是灰的，允许关闭键盘灯
SCREEN_BRIGHT_WAKE_LOCK ：保持CPU 运转，允许保持屏幕高亮显示，允许关闭键盘灯
FULL_WAKE_LOCK ：保持CPU 运转，保持屏幕高亮显示，键盘灯也保持亮度
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版权声明：本文为CSDN博主「llljjlj」的原创文章，遵循 CC 4.0 BY-SA 版权协议，转载请附上原文出处链接及本声明。
原文链接：https://blog.csdn.net/llljjlj/article/details/80631664在含有UI界面的activity、fragment中不推荐使用pm wakelock，推荐使用方法2和3。
@RequiresApi(api = Build.VERSION_CODES.O_MR1)
private void clearKeepScreenOnFlag() {
Activity activity = getActivity();
if (activity != null) {
activity.getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
activity.setTurnScreenOn(false);
}
}
@RequiresApi(api = Build.VERSION_CODES.O_MR1)
private void setKeepScreenOnFlag() {
Activity activity = getActivity();
if (activity != null) {
activity.getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
activity.setTurnScreenOn(true);
}
}
或者
@Nullable
@Override
public View onCreateView(@NonNull LayoutInflater inflater, @Nullable ViewGroup container, @Nullable Bundle savedInstanceState) {
fragmentLayoutRoot=inflater.inflate(R.layout.fragment_dobreath_prepare, container, false);
fragmentLayoutRoot.setKeepScreenOn(true);
mHandler.postDelayed(mCleanKeepScreenTask,120*1000);
return fragmentLayoutRoot;
}下面分析三种方式的功耗分析：
执行方法1.查看dumpsys power信息。
private void wakeLockPm(Context context) {
PowerManager pm = (PowerManager) context.getSystemService(Context.POWER_SERVICE);
PowerManager.WakeLock wakeLock = pm.newWakeLock((PowerManager.SCREEN_BRIGHT_WAKE_LOCK
| PowerManager.ACQUIRE_CAUSES_WAKEUP), "reminder:");
//wakeLock.setReferenceCounted(false);
wakeLock.acquire(6000L);
}
$ adb shell dumpsys power | grep -i wake
no_cached_wake_locks=true
mWakefulness=Awake
mWakefulnessChanging=false
mWakeLockSummary=0x23
mLastWakeTime=4321190 (82051 ms ago)
mHoldingWakeLockSuspendBlocker=true
mWakeUpWhenPluggedOrUnpluggedConfig=true
mWakeUpWhenPluggedOrUnpluggedInTheaterModeConfig=false
mDrawWakeLockOverrideFromSidekick=false
mDoubleTapWakeEnabled=false
Wake Locks: size=1
SCREEN_BRIGHT_WAKE_LOCK 'reminder:' ACQUIRE_CAUSES_WAKEUP ACQ=-1s927ms (uid=10054 pid=8081)
PowerManagerService.WakeLocks: ref count=1
mGravitySensor={Sensor name="gravity Non-wakeup", vendor="qualcomm", version=1, type=9, maxRange=1.0, resolution=0.1, power=0.515, minDelay=20000}
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i screen
mLastScreenBrightnessBoostTime=0 (4406128 ms ago)
mScreenBrightnessBoostInProgress=false
mSuspendWhenScreenOffDueToProximityConfig=true
mDozeAfterScreenOff=false
mMinimumScreenOffTimeoutConfig=5000
mMaximumScreenDimDurationConfig=1000
mMaximumScreenDimRatioConfig=0.20000005
mScreenOffTimeoutSetting=30000
mMaximumScreenOffTimeoutFromDeviceAdmin=9223372036854775807 (enforced=false)
mScreenBrightnessSetting=0
mScreenBrightnessModeSetting=1
mScreenBrightnessOverrideFromWindowManager=-1
mDozeScreenStateOverrideFromDreamManager=0
mDozeScreenBrightnessOverrideFromDreamManager=-1
mScreenBrightnessSettingMinimum=10
mScreenBrightnessSettingMaximum=254
mScreenBrightnessSettingDefault=208
Screen off timeout: 30000 ms
Screen dim duration: 1000 ms
SCREEN_BRIGHT_WAKE_LOCK 'reminder:' ACQUIRE_CAUSES_WAKEUP ACQ=-4s813ms (uid=10054 pid=8081)
上面设置的是wakelock 6秒后自动释放,释放后再看信息
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i wake
no_cached_wake_locks=true
mWakefulness=Asleep
mWakefulnessChanging=false
mWakeLockSummary=0x0
mLastWakeTime=4321190 (177007 ms ago)
mHoldingWakeLockSuspendBlocker=false
mWakeUpWhenPluggedOrUnpluggedConfig=true
mWakeUpWhenPluggedOrUnpluggedInTheaterModeConfig=false
mDrawWakeLockOverrideFromSidekick=false
mDoubleTapWakeEnabled=false
Wake Locks: size=0
PowerManagerService.WakeLocks: ref count=0
mGravitySensor={Sensor name="gravity Non-wakeup", vendor="qualcomm", version=1, type=9, maxRange=1.0, resolution=0.1, power=0.515, minDelay=20000}
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i screen
mLastScreenBrightnessBoostTime=0 (4501875 ms ago)
mScreenBrightnessBoostInProgress=false
mSuspendWhenScreenOffDueToProximityConfig=true
mDozeAfterScreenOff=false
mMinimumScreenOffTimeoutConfig=5000
mMaximumScreenDimDurationConfig=1000
mMaximumScreenDimRatioConfig=0.20000005
mScreenOffTimeoutSetting=30000
mMaximumScreenOffTimeoutFromDeviceAdmin=9223372036854775807 (enforced=false)
mScreenBrightnessSetting=0
mScreenBrightnessModeSetting=1
mScreenBrightnessOverrideFromWindowManager=-1
mDozeScreenStateOverrideFromDreamManager=0
mDozeScreenBrightnessOverrideFromDreamManager=-1
mScreenBrightnessSettingMinimum=10
mScreenBrightnessSettingMaximum=254
mScreenBrightnessSettingDefault=208
Screen off timeout: 5000 ms
Screen dim duration: 1000 ms
使用wakelock可以加tag，方便功耗分析定位问题。
使用该方法的风险在于，必须有正确配对的release方式才不会功耗异常，若没有地方释放就会一直亮屏耗电。如果是在activity中使用，即便是activity 页面pause了，也不会自动release，所以应该尽量避免使用walock的方式。
fragmentLayout.setKeepScreenOn(true);
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i screen
mLastScreenBrightnessBoostTime=0 (5352101 ms ago)
mScreenBrightnessBoostInProgress=false
mSuspendWhenScreenOffDueToProximityConfig=true
mDozeAfterScreenOff=false
mMinimumScreenOffTimeoutConfig=5000
mMaximumScreenDimDurationConfig=1000
mMaximumScreenDimRatioConfig=0.20000005
mScreenOffTimeoutSetting=30000
mMaximumScreenOffTimeoutFromDeviceAdmin=9223372036854775807 (enforced=false)
mScreenBrightnessSetting=0
mScreenBrightnessModeSetting=1
mScreenBrightnessOverrideFromWindowManager=-1
mDozeScreenStateOverrideFromDreamManager=0
mDozeScreenBrightnessOverrideFromDreamManager=-1
mScreenBrightnessSettingMinimum=10
mScreenBrightnessSettingMaximum=254
mScreenBrightnessSettingDefault=208
Screen off timeout: 30000 ms
Screen dim duration: 1000 ms
SCREEN_BRIGHT_WAKE_LOCK 'WindowManager' ON_AFTER_RELEASE ACQ=-23s285ms (uid=1000 pid=1400 ws=WorkSource{10054})
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i wake
no_cached_wake_locks=true
mWakefulness=Awake
mWakefulnessChanging=false
mWakeLockSummary=0x23
mLastWakeTime=5285832 (69745 ms ago)
mHoldingWakeLockSuspendBlocker=true
mWakeUpWhenPluggedOrUnpluggedConfig=true
mWakeUpWhenPluggedOrUnpluggedInTheaterModeConfig=false
mDrawWakeLockOverrideFromSidekick=false
mDoubleTapWakeEnabled=false
Wake Locks: size=1
SCREEN_BRIGHT_WAKE_LOCK 'WindowManager' ON_AFTER_RELEASE ACQ=-26s761ms (uid=1000 pid=1400 ws=WorkSource{10054})
PowerManagerService.WakeLocks: ref count=1
mGravitySensor={Sensor name="gravity Non-wakeup", vendor="qualcomm", version=1, type=9, maxRange=1.0, resolution=0.1, power=0.515, minDelay=20000}
执行view.setkeepScreenon(true)不受抬腕影响。view pause或destroy时，会自动释放SCREEN_BRIGHT_WAKE_LOCK，推荐使用这种方式。
方法3：
在activity中执行
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setTurnScreenOn(true);
$ adb shell dumpsys power | grep -i wake
no_cached_wake_locks=true
mWakefulness=Awake
mWakefulnessChanging=false
mWakeLockSummary=0x23
mLastWakeTime=5636910 (28381 ms ago)
mHoldingWakeLockSuspendBlocker=true
mWakeUpWhenPluggedOrUnpluggedConfig=true
mWakeUpWhenPluggedOrUnpluggedInTheaterModeConfig=false
mDrawWakeLockOverrideFromSidekick=false
mDoubleTapWakeEnabled=false
Wake Locks: size=1
SCREEN_BRIGHT_WAKE_LOCK 'WindowManager' ON_AFTER_RELEASE ACQ=-22s316ms (uid=1000 pid=1400 ws=WorkSource{10054})
PowerManagerService.WakeLocks: ref count=1
mGravitySensor={Sensor name="gravity Non-wakeup", vendor="qualcomm", version=1, type=9, maxRange=1.0, resolution=0.1, power=0.515, minDelay=20000}
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i screen
mLastScreenBrightnessBoostTime=0 (5670577 ms ago)
mScreenBrightnessBoostInProgress=false
mSuspendWhenScreenOffDueToProximityConfig=true
mDozeAfterScreenOff=false
mMinimumScreenOffTimeoutConfig=5000
mMaximumScreenDimDurationConfig=1000
mMaximumScreenDimRatioConfig=0.20000005
mScreenOffTimeoutSetting=30000
mMaximumScreenOffTimeoutFromDeviceAdmin=9223372036854775807 (enforced=false)
mScreenBrightnessSetting=0
mScreenBrightnessModeSetting=1
mScreenBrightnessOverrideFromWindowManager=-1
mDozeScreenStateOverrideFromDreamManager=0
mDozeScreenBrightnessOverrideFromDreamManager=-1
mScreenBrightnessSettingMinimum=10
mScreenBrightnessSettingMaximum=254
mScreenBrightnessSettingDefault=208
Screen off timeout: 30000 ms
Screen dim duration: 1000 ms
SCREEN_BRIGHT_WAKE_LOCK 'WindowManager' ON_AFTER_RELEASE ACQ=-27s602ms (uid=1000 pid=1400 ws=WorkSource{10054})
效果与方法2相同，activity pause后自动释放，再次resume自动screen_bright_wake_lock。
为了避免用户误操作到该页面长时间亮屏耗电，建议加入超时释放逻辑。
方法4：
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i wake
no_cached_wake_locks=true
mWakefulness=Awake
mWakefulnessChanging=false
mWakeLockSummary=0x23
mLastWakeTime=5733001 (174149 ms ago)
mHoldingWakeLockSuspendBlocker=true
mWakeUpWhenPluggedOrUnpluggedConfig=true
mWakeUpWhenPluggedOrUnpluggedInTheaterModeConfig=false
mDrawWakeLockOverrideFromSidekick=false
mDoubleTapWakeEnabled=false
Wake Locks: size=1
SCREEN_BRIGHT_WAKE_LOCK 'WindowManager' ON_AFTER_RELEASE ACQ=-8s160ms (uid=1000 pid=1400 ws=WorkSource{10054})
PowerManagerService.WakeLocks: ref count=1
mGravitySensor={Sensor name="gravity Non-wakeup", vendor="qualcomm", version=1, type=9, maxRange=1.0, resolution=0.1, power=0.515, minDelay=20000}
lingx@MI-20170703YUWL MINGW64 /e/watch/Apps/fitness (master)
$ adb shell dumpsys power | grep -i screen
mLastScreenBrightnessBoostTime=0 (5909168 ms ago)
mScreenBrightnessBoostInProgress=false
mSuspendWhenScreenOffDueToProximityConfig=true
mDozeAfterScreenOff=false
mMinimumScreenOffTimeoutConfig=5000
mMaximumScreenDimDurationConfig=1000
mMaximumScreenDimRatioConfig=0.20000005
mScreenOffTimeoutSetting=30000
mMaximumScreenOffTimeoutFromDeviceAdmin=9223372036854775807 (enforced=false)
mScreenBrightnessSetting=0
mScreenBrightnessModeSetting=1
mScreenBrightnessOverrideFromWindowManager=-1
mDozeScreenStateOverrideFromDreamManager=0
mDozeScreenBrightnessOverrideFromDreamManager=-1
mScreenBrightnessSettingMinimum=10
mScreenBrightnessSettingMaximum=254
mScreenBrightnessSettingDefault=208
Screen off timeout: 30000 ms
Screen dim duration: 1000 ms
SCREEN_BRIGHT_WAKE_LOCK 'WindowManager' ON_AFTER_RELEASE ACQ=-10s177ms (uid=1000 pid=1400 ws=WorkSource{10054})
从现象看与方法2、3效果相同。但实际使用有很大区别，因为在xml中设置了keepScreenOn=true，在代码中执行getWindow().clearFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
setTurnScreenOn(false);
后发现SCREEN_BRIGHT_WAKE_LOCK并未释放。因此只有当确定本页面显示时不会被息屏才能在xml中配置亮屏，例如一个闪屏页面，过度页面，这些页面一般持续时间不能太长。
综上所述：
1. 如果是在receiver、broadcast中亮屏、唤醒cpu，只能使用wakelock，建议使用wakelock.acquire(xxxx)带参数的。
必须有地方释放wakelock，否则会持续亮屏、cpu活跃会对功耗有较大影响。
2. 如果是在activity、fragment等包含view 资源的页面中亮屏，建议使用方法2、3，设置view.setKeepScreenOn(true);
或者设置WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON 和 setTurnScreenOn(true);
3.如果是闪现过度页面，可以使用方法4在xml中配置keepScreenOn=true，因为这类页面持续时间短，也不需要考虑自动释放机制。
方法234所显示的页面，只要页面退到后台后都会自动释放SCREEN_BRIGHT_WAKE_LOCK。所以在包含view的页面中，尽量避免方法1。