Develop Reference

isActivityStartAllowedOnDisplay() method

I'm trying to launch a second activity on a secondary display. This works fine on the emulators, but I need the secondary display to handle touch events.
With Android Pie, launching an activity on some second displays would throw a security exception. Google recently pushed out this new API for Android Q - isActivityStartAllowedOnDisplay() (https://developer.android.com/reference/android/app/ActivityManager.html#isActivityStartAllowedOnDisplay(android.content.Context,%2520int,%2520android.content.Intent)) - to be able to tell if the second display has this security exception or not.
This new API is helpful, BUT, is there any way around it? Maybe I've misunderstood the documentation, but it seems like if the device doesn't support it, then there's no way around it. Does anyone know of any displays that will NOT throw this security exception?

In order to get touch events to register on the secondary display (GeChic Touch Monitor), I had a DisplayLink device connected between the Android device and touch display. At this point, it was mirroring the view on the phone/tablet but would handle touch events. So, I wrote an app that would attempt to launch a second activity on the second display using this code on Android Pie OS:
DisplayManager mgr = (DisplayManager) this.getBaseContext().getSystemService(Context.DISPLAY_SERVICE);
if (mgr != null) {
Display[] displays = mgr.getDisplays();
for (int i = 0; i < displays.length; i++) {
Display display = displays[i];
Point point = new Point();
display.getSize(point);
if (point.y == PX_HEIGHT_OF_SECONDARY_DISPLAY || point.x == PX_HEIGHT_OF_SECONDARY_DISPLAY) {
Context displayContext = createDisplayContext(display);
Intent newIntent = new Intent(displayContext, ActivityCID.class);
ActivityOptions options = ActivityOptions.makeBasic();
options.setLaunchDisplayId(display.getDisplayId());
newIntent.addFlags(Intent.FLAG_ACTIVITY_MULTIPLE_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(newIntent, options.toBundle());
return;
}
}
}
Note that I did not use display.getDisplayId() and did a hacky way with the point.y and point.x values with a pixel width or height that did not match the pixel width or height of the Android phone/tablet. The displayId() was not always a consistent value which "should" be stable in Android Q. This is where the app would crash and the second activity would fail with a security permissions error. So, I used Android Q Beta to test the new isActivityStartAllowedOnDisplay() API. I ran this through Android Studio onto the phone (which was on Android Q Beta OS) to run it and to no surprise, the secondary display came back false. See code below:
public void launchOnSecondaryDisplay(Display display) {
Context displayContext = createDisplayContext(display);
Intent newIntent = new Intent(displayContext, ActivityTest.class);
ActivityManager activityManager = (ActivityManager) getApplicationContext().getSystemService(Activity.ACTIVITY_SERVICE);
if (activityManager != null) {
boolean allowsDisplay = activityManager.isActivityStartAllowedOnDisplay(displayContext, display.getDisplayId(), newIntent);
if (allowsDisplay) {
ActivityOptions options = ActivityOptions.makeBasic();
options.setLaunchDisplayId(display.getDisplayId());
newIntent.addFlags(Intent.FLAG_ACTIVITY_MULTIPLE_TASK | Intent.FLAG_ACTIVITY_NEW_TASK);
startActivity(newIntent, options.toBundle());
} else {
Toast.makeText(this, "Cannot start activity on that display as it is not supported.", Toast.LENGTH_LONG).show();
}
}
}
I decided to try this through the command line. After networking the physical device to match my Mac's connected network, I was able to connect to the phone wirelessly and was able to make changes in adb. Using an adb command, I was able to get a secondary activity on the secondary display! It seemed to be working! But no, it was not... Touch events still continued to act like the device was being mirrored so this was still a problem and was not going to work.
I discussed this with the Googler as well and was explained that adb root can override these permissions. However, there was still no way to get the touch events to map to the second activity on the secondary display.
At the moment of writing this, the only supported way to test multi touch displays is to use a physical device running Android Q Beta and follow these steps:
enable developer options,
in developer options, enable these 4 options: Force All Activities to be Resizeable, Freeform Windows, Force Desktop, and Simulate Secondary Display (doesn't matter which option picked for simulate secondary display),
reboot the device,
connect a mouse to the device. The mouse will show up and be stuck inside the overlaying window that is "simulating the secondary display". This will handle touch events.
In the future, there will be emulators that have multiple displays to better test multi display applications but this is not available at the moment.

android open battery settings programically

I'm looking for a way to open the battery settings screen from an android app.
So far I found the two intents :
Intent.ACTION_POWER_USAGE_SUMMARY
Settings.ACTION_BATTERY_SAVER_SETTINGS
but none of them open this screen.
I was wondering if anyone knows of such a way. It sounds strange that an intent for something so simple doesn't exist

Settings.ACTION_BATTERY_SAVER_SETTINGS on "plain" Android versions will show the settings page you want to show.
Intent.ACTION_POWER_USAGE_SUMMARY will lead to the overview page showing the battery consumption.
Some manufactures such as Samsung build their own implementation over the system one, e.g. in this the "Battery" page. On Samsung devices, you can call this by calling the SmartManager interface directly. An code example:
if (Build.MANUFACTURER == "samsung") {
val intent = Intent()
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.N) {
intent.component = ComponentName("com.samsung.android.lool", "com.samsung.android.sm.ui.battery.BatteryActivity")
} else if (Build.VERSION.SDK_INT > Build.VERSION_CODES.LOLLIPOP) {
intent.component = ComponentName("com.samsung.android.sm", "com.samsung.android.sm.ui.battery.BatteryActivity")
}
try {
activity?.startActivity(intent);
} catch (ex: ActivityNotFoundException) {
// Fallback to global settings
startActivity(Intent(Settings.ACTION_SETTINGS))
}
} else {
startActivity(Intent(Settings.ACTION_BATTERY_SAVER_SETTINGS))
}
It can be the case that you need additional cases for Huawei or Xiaomi as well.
Huawei can be "com.huawei.systemmanager", "com.huawei.systemmanager.optimize.process.ProtectActivity"...
...and the MIU based ones "com.miui.securitycenter", "com.miui.permcenter.autostart.AutoStartManagementActivity"

I know this is quite old. But a trick I use is going to the appropriate settings screen in the device settings and then while connected to the phone run:
adb shell
dumpsys window windows | grep -E 'mCurrentFocus'
This returns the package name and Activity name currently in focus.
Using that I can check in code if the intent is callable. If it is, I launch it. If it isnt, I might have better luck with a different screen that is near by or explain to the user he needs to do something manually etc... Obviously the more devices you have, the more Intents you can create and check at run time. Im sure there is a list of Intents for different devices online.

Setup a new user after it's created

From my device owner application, I'd like to create a new user and switch directly to it. For now, I can only create a new user, switch to it but:
it brings me to the keyguard screen, that I need to manually unlock.
then, tells me to setup the newly created user - with firstname, lastname, WIFI settings, and 3 Google usage statistics/reporting options.
I'd like to know if there's a way to programmatically setup the new user and switch directly to it's "session". I'd like to programmatically avoid the "unlock" page et pre-setup the newly created user with name, WIFI settings, but also available apps and security settings.
here's what I do so far :
// init block (in onCreate...)
DevicePolicyManager mDPM = (DevicePolicyManager) this.getSystemService(Context.DEVICE_POLICY_SERVICE);
ComponentName mDeviceAdminRcvr = new ComponentName(this, DeviceAdminRcvr.class);
// in my button "create a new user"
ComponentName profileOwnerComponent = new ComponentName(this, ProfileAdminRcvr.class);
Bundle adminExtras = new Bundle();
UserHandle userHandle = mDPM.createAndInitializeUser(mDeviceAdminRcvr, name, ownerName, profileOwnerComponent, adminExtras);
// TODO : place here missing instructions to provision the user...
mDPM.switchUser(mDeviceAdminRcvr, userHandle);
I couldn't find any documentation on the official Google page about device owner apps or profile apps.
Could anyone help me or point me to useful links ?

As far as I've seen, there is no way to programmatically unlock the screen lock. Even the Smart lock functionnality added in Lollipop will just disable the Key Guard, which means that the "PIN" or "Pattern" will transform into a "Swipe Lock" when a trusted agent unlocks the device. Even in this case, you'll need to manually swipe the screen to unlock the device.
Concerning the second point, it's possible to avoid the "Setup Wizard" proposed the first time you unlock a newly created user. Here's how to do it :
in your ProfileAdminRcvr.java, you'll need to hide the system application called com.google.android.setupwizard. You could do this in the onEnabled() method of your DeviceAdminReceiver's implementation (the one you set for your profile when creating the user).
To complete this, you can disable the "first use hint", by setting the Settings.Secure.SKIP_FIRST_USE_HINTS property.
Here's the code to do it :
public class ProfileOwnerRcvr extends DeviceAdminReceiver {
private DevicePolicyManager mDPM;
private ComponentName mProfileAdminRcvr;
#Override
public void onEnabled(Context context, Intent intent) {
mDPM.setProfileName(mProfileAdminRcvr, "My new user");
// ... setup other things by yourself...
mDPM.setApplicationHidden( mProfileAdminRcvr, "com.google.android.setupwizard", true);
mDPM.setSecureSetting(mProfileAdminRcvr, Settings.Secure.SKIP_FIRST_USE_HINTS, "1");
}

Google updated its demo app to use Android-N preview version, it seems that there will be a flag called DevicePolicyManager.SKIP_SETUP_WIZARD to do part of what you are trying to do (i.e skipping the wizard) in N.

Unknown sources settings android

The issue is that I need to install an apk(non market app) and for this, the user need to activate the unknown source setting, so i send him (if he didn't have it activated) to the settings so he can turn on the option, the issue is that i tested it in different phones and in samsung that option is on applications while in htcs phones is on security. i want send the user to that option but i don't know how to do it
I read about this and no one knows exactly how to do it
this is my code
int canInstallFromOtherSources = Settings.Secure.getInt(ctx2,Settings.Secure.INSTALL_NON_MARKET_APPS);
if(canInstallFromOtherSources == 0)
{
Intent intentSettings = new Intent();
intentSettings.setAction(android.provider.Settings.ACTION_APPLICATION_SETTINGS);
startActivity(intentSettings);
}

You can do it with the following line (changing to the corresponding action):
startActivityForResult(new Intent(Settings.ACTION_LOCATION_SOURCE_SETTINGS), REQUEST_CODE_ENABLE_LOCATION_PROVIDERS);
Check Android Settings documentation.
I think you should use ACTION_SECURITY_SETTINGS and one of ACTION_APPLICATION_SETTINGS or ACTION_APPLICATION_DEVELOPMENT_SETTINGS.
And here (line 304), you've got a working example of one of my apps: Tureame

Unlock automatically when android phone booted

I had caught phone boot event.
On boot complete event I am writing following code
KeyguardManager mKeyguardManager = (KeyguardManager) mContext.getSystemService(KEYGUARD_SERVICE);
KeyguardLock mLock = mKeyguardManager.newKeyguardLock("MyApp");
mLock.disableKeyguard();
but what happing I can able to see lock and after that screen is getting unlocked. But requirement is that lock should not be visible at all after booting.
My guess is that I need to make modification in framework somewhere in setting file.
But I don't know where to modify.

but what happing I can able to see lock and after that screen is getting unlocked
You did not lock the screen. Hence, you cannot unlock it. disableKeyguard() is only used to reverse the effects of reenableKeyguard().
My guess is that I need to make modification in framework somewhere in setting file.
If by "setting file" you mean "Java, or possibly C/C++, source code", then yes that is probably the case.
But I don't know where to modify.
StackOverflow is not a great resource for assistance with firmware modifications, sorry.

I have did it by commenting following code in KeyguardViewMediator
private void showLocked() {
/* if (DEBUG) Log.d(TAG, "showLocked");
Message msg = mHandler.obtainMessage(SHOW);
mHandler.sendMessage(msg);*/
}