Develop Reference

How to set On/Off Timers on Android 9 using ADB?

I am trying to set an automatic on/off timer for a device that is running Android 9 (For examples sake let's say I want it to turn on at 9 AM and turn off at 5PM) This must happen daily.
I want this to be done using adb commands so that it can be automated down the line.
If I go into settings I can navigate as so: Settings > Accessibility > Scheduled Power on and off
once in here I can set the Power off time, Power on time and the 2 relative Repeats
Any changes I make (physically or via adb) are then required to be confirmed by pressing the Save Settings button at the bottom of the screen.
Pressing the Save Settings button triggers the introduction of multiple variables:
close_machine_time_hour
close_machine_time_mins
open_machine_time_hour
open_machine_time_mins
power_off_cycle_mode
power_on_cycle_mode
power_off_date
power_on_date
power_way
machine_time_secs
Of which the 2 I am most concerned about are the last 2 as these seem like odd variables to only introduce when activating a niche setting (I feel as though they should either be there always)
Question 1: would be is this a standard Android feature? Or is this something that has been done for custom ROM?
I have tried setting all the settings as they appear in settings grabbed using command adb shell settings list system
They are set individually using the commands below:
adb shell settings put system timer_power_switch_settings 1
adb shell settings put system close_machine_time_hour 09
adb shell settings put system close_machine_time_mins 00
adb shell settings put system open_machine_time_hour 17
adb shell settings put system open_machine_time_mins 00
adb shell settings put system power_off_time 9:00:16
adb shell settings put system power_on_time 17:00:16
adb shell settings put system power_off_cycle_mode 0-1-2-3-4-5-6-
adb shell settings put system power_on_cycle_mode 0-1-2-3-4-5-6-
You'll note that in essence I am setting the time twice, which is quite odd.
The key thing is that none of this works unless I physically press the save button (despite showing visual feedback on the device screen that values change as I alter them via adb). Which is fine for 1 device but will become quite laborious if it needs to be done for 30+ devices at a time.
Question 2: Is there to simulate this Save Settings button click without simulating a tap on screen? Or to bypass this setting entirely?
Question 2.A: Is there a way to continuously monitor activity using an adb command? so I can run it, then click the button, and it will show me what's going on in the background?

android 6.0.1 force wifi connection with no internet access

this has many similar questions (google for: "no internet access detected. won't automatically reconnect." or: android force wifi connection programmatically).
i thought i had a answer here, but it stopped working after installing 6.0.1 updates (i have may 1 security patches).
seems like this is a behaviour change.
i have some 2013 nexus 7's with 6.0.1 that run a kiosk type app and want to connect programmatically to a specific wireless network that has no internet connection. each tablet has a unique static ip address of the form: 192.168.0.xx. i use the normal java socket constructors and check to see if the interface is up using: NetworkInterface.getNetworkInterfaces().
a manual connection has been made. sometimes there is a dialog that asks whether or not you want to always connect. i always check yes.
but the wifi says: "no internet access detected. won't automatically reconnect" after the router cycles power.
doing a disconnect, enable, reconnect does not work. at best it gets: ip6-localhost/::1.
has anyone had any luck using a request object, or bindProcessToNetwork?
edit: related.
edit: the problem seems to be with: CAPTIVE_PORTAL_DETECTION_ENABLED - this string seems to be defined in the source:
public static final String
CAPTIVE_PORTAL_DETECTION_ENABLED = "captive_portal_detection_enabled";
...
MOVED_TO_GLOBAL.add(Settings.Global.CAPTIVE_PORTAL_DETECTION_ENABLED);
but throws" android.provider.Settings$SettingNotFoundException: captive_portal_detection_enabled when used explicitly and is not visible to android studio.
also, doing a settings list global does not contain the constant.
edit doing a adb shell settings put global captive_portal_detection_enabled 0 does seem to work, but this can not be done in the field when the router cycles power. this value seems to persist when the tablet cycles power. and now this value shows up in a settings list global. also, using the raw string: Settings.Global.getInt(getContentResolver(),"captive_portal_detection_enabled"); now returns 0.
edit: looks like setting it requires: android.permission.WRITE_SECURE_SETTINGS, but of course this fails when put into the manifest since we are not a system app.
edit: trying to exec the shell command throws: java.lang.SecurityException, so it looks like you need to issue the command from adb :(
thanks

Could you try and set the global setting captive_portal_detection_enabled to 0 (false).
What's actually happening is that by default, everytime you connect to a wifi, the FW will test against a server (typically google) to see if it's a captive wifi (needs login). So if your wifi is not connected to google, this check will fail. After that, the device knows that wifi has no internet connection and simply will not autoconnect to it.
Setting this setting to 0, will avoid this check.
Programatically Settings.Global.putInt(getContentResolver(), Settings.Global.CAPTIVE_PORTAL_DETECTION_ENABLED, 0);
You can do it through adb for testing purposes:
adb shell settings put global captive_portal_detection_enabled 0
And retrieve it's value like this:
adb shell settings list global | grep "captive"
IMHO this is not very nice thing to do, since you are changing a setting for the user and many FWs don't provide even an advanced setting to enable/disable this by the user itself. (Google doesn't). But maybe it suits your needs.
Hope it helps!

A non-root solution which is a kind of hack tech. :P
Reboot phone, connect to the non-Internet Wifi;
Go to Settings and create a new user;
Continue, continue, and continue until you see "Checking connection";
As soon as you see "checking connection", switch off your phone;
Switch on your phone again, you will be in "Owner" user, keep it;
Toggle Wifi, and the exclamation mark should disappear quickly :)
Remove that new user or just leave it there;
I don't know why, but it works...

Programmatically enable/disable "Battery Saver" mode

I am trying to find if I can enable and/or disable Android's built-in "Battery Saver" mode programmatically.
Any official approaches, or trickery, are welcome.
For reference, here is how to do it following Android's standard UI in 5.0:
http://www.androidcentral.com/android-50-lollipop-basics-how-get-more-life-between-charges-battery-saver
I am aware you can detect it -- that is not what I am after.
Thanks all.

You can enable/disable Battery Saver programmatically on rooted devices. You have to edit the low_power value in global table, in /data/data/com.android.providers.settings/databases/settings.db file.
If your device supports settings command, you can execute (as root):
settings put global low_power 1
to enable Energy Saver and
settings put global low_power 0
to disable it.
If it doesn't, use sqlite3 command:
sqlite3 /data/data/com.android.providers.settings/databases/settings.db "update global set value='1' where name='low_power';"
sqlite3 /data/data/com.android.providers.settings/databases/settings.db "update global set value='0' where name='low_power';"
Remember that you have to unplug your phone from PC first, otherwise system will disable Energy Saver. Use ADB over WiFi or Android Terminal (Emulator).
UPDATE:
The sqlite3 method doesn't seem to be reliable anymore.
I'm not sure if android.os.action.POWER_SAVE_MODE_CHANGED broadcast gets send. Maybe you have to send it manually, like in code from here:
private static String COMMAND_ENABLE = "settings put global low_power 1\n" +
"am broadcast -a android.os.action.POWER_SAVE_MODE_CHANGED --ez mode true\n";
private static String COMMAND_DISABLE = "settings put global low_power 0\n" +
"am broadcast -a android.os.action.POWER_SAVE_MODE_CHANGED --ez mode false\n";
Also, it's been reported that a new power_saving entry appeared in settings database, however in Android 6.0.1 I haven't managed to find it. In Android 7.1.1_r13 low_power is still used internally (e.g. here), however it may get changed in some Android release. You may want to keep checking changes in e.g. this and this file.

You cannot without rooting your phone. I am not sure why this is the case, especially where location services are required now for viewing scan results since SdkVersion 23+ .
This issue is very revealing.
https://code.google.com/p/android/issues/detail?id=185370
The best answer is application developers are being forced to crowd source network location for their google overlords. Notice, the OS itself has no problem displaying scan results without location services on.
Revealing that there is no way to turn on location services without GPS where location services are inactive. This two step shuffle is a major quality of experience issue for users. Turn location services on, then turn GPS off.
Watch this space, more lock downs on the way.

How to access Power Saving Mode Programmatically in Android?

I need to access to programmatically turn ON & OFF Power Saving Mode in android.
Is there any API for this ? As I can see Power Saving mode option is not available
for all mobile devices, is there any code to check these settings availability and if available then turn it ON and OFF ?
Also is there any work around ?

If you want to test the Power Saving Mode (PSM):
The following works with Android Studio 3.4.1 and a Google Pixel 2 XL phone:
$ adb shell dumpsys battery unplug # a charging device cannot enter PSM
$ adb shell settings put global low_power 1 # enter Power Saving Mode (PSM)
This only works on devices that has the standard Power Saving Mode, like Samsung's, but not Huawei's, for example. On some Samsung devices, this setting is stored in global setting keyed psm_switch, as mentioned above.
You can leave PSM by setting low_power to 0 or by enabling charging again with:
$ adb shell dumpsys battery reset
Source: https://developer.android.com/training/monitoring-device-state/doze-standby#testing_doze_and_app_standby

It's bad practice to control the user's device settings from your app.
Rather consider suspending background services when battery levels are low.
Or to notify the user of low battery power and advising the user to switch of unnecessary settings like Bluetooth or WiFi.

Most devices won't have a built-in power-saver API, so you could try to make your own power-saver mode by turning off the bluetooth if it's on, the wi-fi, etc, deactivating location in settings, or checking for other power-eating options enabled.

There are no available API's to do this in android SDK. however You can control/save the power by Turning off Blutooth,Wi-Fi and other unused sevices inside your coding.

You can't set the power saving mode programmatically. Allowing this would be a bad idea.
On certain Samsung devices you can check if it is enabled:
final String result = Settings.System.getString(getContentResolver(), "psm_switch");
Log.v("Debug", "Powersaving active: " + TextUtils.equals(result, "1"));
See this for more info: https://stackoverflow.com/a/39296959/3600178

Can't change battery configuration in Android Emulator

I'm trying to change in my emulator the battery status as capacity and ac status but isn't working.
I made the whole steps:
1) Connected to the emulator via telnet;
2) Tried to use the commands such power ac off and power capacity 70
3) Every time I checked the power display, the same configuration appears and no change I input is save, and the emulator always show the battery with a "!".
FR I saw this link Change emulator battery level in Windows, tried it and nothing resolved.
Follow my data about the battery:
power display
AC: online
status: Not charging
health: Dead
present: false
capacity: 0
Thank you!

It seems like your emulator device has battery option turned off.
You can change AVD battery configuration through:
Open AVD configuration file:
Default location for Linux/MAC
~/.android/avd/<AVD name>.avd/config.ini
Default location for Windows XP
C:\Documents and Settings\<user>\.android\avd\<AVD name>.avd\config.ini
Default location for Windows Vista and later
C:\Users\<user>\.android\avd\<AVD name>.avd\config.ini
Change the line:
hw.battery=no
to
hw.battery=yes

You made right. I did it on my computer and sometimes it did not worked too, I just had to set battery status to discharging before setting its capacity.
power status discharging
Additionally there is a nice tutorial that could help you with additional commands:
http://www.stealthcopter.com/blog/2010/07/changing-the-battery-percentage-in-an-avd-android-virtual-device-emulator/