Turn on screen on device

问题

How can I turn the sceen on ?

I tried something like this

adb -d  shell am broadcast -a android.intent.action.SCREEN_ON

It really should work, I send broadcast intent it is received by the system, but the screen doesn't turn on

I do not understand what is the problem, is it possible to turn the screen of the device by code ? I mean with software ? Cause it seems like the turning on of the screen is done just by the hardware button press . . . at least I got that felling , am I wrong ?

回答1:

I could be wrong about this, but...

You shouldn't think of broadcasts as something to send to get things done, but instead think of them as things that are sent when things are done.

I think the system sends 'android.intent.action.SCREEN_ON' when screen is goes on, but sending 'android.intent.action.SCREEN_ON' does not necessarily make the screen go on.

I hope this makes sense.

For the answer, you can find it in...

Calling hidden API in android to turn screen off
turn the screen on/off in Android with a shake

回答2:

adb shell input keyevent KEYCODE_POWER

Works to turn on screen (when display is off) Works to turn off screen (when display is on/awake)

回答3:

For Android 5.0 and above:

adb shell input keyevent KEYCODE_WAKEUP

adb shell input keyevent 224

Ref:

Wakes up the device. Behaves somewhat like KEYCODE_POWER but it has no effect if the device is already awake.

Note: KEYCODE_POWER added in API level 1, while KEYCODE_WAKEUP added in API level 20!

回答4:

u can turn it on/off if u do like:

adb shell
@shell: input keyevent 26
@shell: (enter or via hidden command empty line)
@shell: exit

this worked for me on some android versions ;)
(NOTE: this will turn the screen on and off, depends on the actual screen state)

To detect the current state of the screen u can use the following ways:
Android < 5.x.x
adb shell dumpsys input_method
In the output search for mScreenOn=true/false

Android >= 5.x.x
adb shell dumpsys display
In the output search for mScreenState=ON/OFF

In my scripts i use this \s{0,}mScreen(State|On)=(?<STATE>(true|false|on|off))\s{0,} (Compiled|IgnoreCase|ExplicitCapture) regular expression for both outputs to detect the current state.

EDIT (16.03.2018):

There is also another way to detect the screen state, it works since Android 3.0. The dumpsys window policy command will give us all we need. - In the output search for mScreenOn(Fully)?=(?<STATE>(true|false)). There are also other useful informations like: