The Context
Recently, I have been looking for reliable ways to control a secured Android Keyguard. Mainly to display a custom lock screen. I know that Google had stated custom lock screens are not officially supported by the platform and should expect things to break, however, with the existing APIs, I believe there must be ways to do this. I have done tons of research for about a week but still having problem here and there. What I have implemented, assuming a secured Keyguard is enabled, so far are,
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED allows an activity(a window) to be displayed on screen on, putting the Keyguard behind, and all unsafe actions are prevented. Notification panel is disabled, finishing the activity will bring up the Keyguard. I implemented as following in my lock screen activity.
#Override
public void onAttachedToWindow() {
window.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
}
KeyguardManager, KeyguardManager.KeyguardLock are deprecated classes, but they still work all the way to Jelly Bean. To do this, I have a Service that handles two things, holding a static KeyguardManager and the related objects, and have it hold a BroadcastReceiver to receive Intent.ACTION_SCREEN_ON and Intent.ACTION_SCREEN_OFF. (all the objects are initialized properly)
For ScreenReceiver
public static synchronized void disableKeyguard() {
if ( isLocked ) {
if ( keyguardLock == null ) {
keyguardLock = keyguardManager.newKeyguardLock(LOG_TAG);
}
keyguardLock.disableKeyguard();
isLocked = false;
}
}
public static synchronized void reenableKeyguard() {
if ( !isLocked ) {
if ( keyguardLock == null ) {
keyguardLock = keyguardManager.newKeyguardLock(LOG_TAG);
}
keyguardLock.reenableKeyguard();
keyguardLock = null;
isLocked = true;
}
}
For BroadcastReceiver
#Override
public void onReceive( Context context, Intent intent ) {
if ( intent.getAction().equals(Intent.ACTION_SCREEN_ON) ) {
Intent start = new Intent(context, LockScreen.class);
start.addFlags(Intent.FLAG_ACTIVITY_CLEAR_TOP | Intent.FLAG_ACTIVITY_NEW_TASK | Intent.FLAG_ACTIVITY_CLEAR_TASK);
context.startActivity(start);
} else if ( intent.getAction().equals(Intent.ACTION_SCREEN_OFF) ) {
ScreenReceiverService.reenableKeyguard();
}
}
For LockScreenActivity, when the user had input the correct passcode,
window.clearFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
ScreenReceiverService.disableKeyguard();
finish();
The Problem
Things that works
ACTION_ON and ACTION_OFF are received reliably.
LockScreenActivity is shown before the Keyguard (without telephone state handling yet)
Notification cannot be pulled down, exiting the activity in any way would display the lockscreen.
Things that does not work
After I disable Keyguard and call finish(), my app exits and homescreen or the last activity before the screen went off is shown. However, whenever I press the Home Key, the Keyguard will flash into the screen, quickly dismissing itself immediately, and the normal Home Key function/event is not handled (will not return to homescreen after flashing). This is observed when I rapidly tapped the Home Key repeatedly.
I even looked into the Android source code to find out the Home Key handling, but it is never sent to third-party applications unless the window type is WindowManager.LayoutParams.TYPE_KEYGUARD or WindowManager.LayoutParams.TYPE_KEYGUARD_DIALOG, which will throw SecurityException on 4.0+ even it worked on earlier platforms. And for the Keyguard, I have declared DISABLE_KEYGUARD permission use this shouldn't be the problem. My guess is the flag FLAG_SHOW_WHEN_LOCKED will tell the system to handle to Keyguard in some ways that would conflict with other disable calls. Since this flag is mostly used for Alarm/SMS type application, which is to show limited information to the user, then dismiss themselves and bring up the Keyguard. But in my case, having the user unlock my lock screen then unlock the system lockscreen simply defeats the purpose of my app.
So the question is why would the Keyguard flashes whenever I press Home after I disabled it? Is there any workaround/solution for this issue?
P.S. Thank you for reading such a long question. This is my first time asking a question here, if there is anything that I did wrong, please tell me (i.e. format, grammar, code convention, tags, etc.). Also I had no experience with any programming knowledge, I started with Android before I know what Java is. So I have not taken any proper course/training yet, this community is awesome and often help people like I even if they are simple questions, and of course watching Google I/O videos, reading blogs, read others' code help me a lot. So please tolerate any dumb mistakes/obvious bugs/stupid questions. I am only 16. ^_^"
I have used this with some success in both Gingerbread and ICS to open my activity (via a background service which is starting it). In the activity being started:
#Override
public void onAttachedToWindow() {
this.getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN |
WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD |
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON,
WindowManager.LayoutParams.FLAG_FULLSCREEN |
WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD |
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
}
I had the same problem for the click of HOME button while unlocking the device. This can be solved by reseting the password to blank (ie "") :
DevicePolicyManager devicePolicyManager;
ComponentName demoDeviceAdmin;
devicePolicyManager.setPasswordQuality(demoDeviceAdmin,DevicePolicyManager.PASSWORD_QUALITY_UNSPECIFIED);
devicePolicyManager.setPasswordMinimumLength(demoDeviceAdmin, 0);
devicePolicyManager.resetPassword("",DevicePolicyManager.RESET_PASSWORD_REQUIRE_ENTRY);
and then disabling the keygaurd :
this.keyGuardLock = ((KeyguardManager)getSystemService("keyguard")).newKeyguardLock("keyguard");
keyGuardLock.disableKeyguard();
Hope this solved your problem. \m/ keep coding!
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED allows an activity(a
window) to be displayed on screen on, putting the Keyguard behind
I tried to get this but my activity always preceded by the system lock screen. isOrderdBroadcast() says that ACTION_SCREEN_NO is an ordered broadcast.
I added flag to the activity :
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
in onAttachedView(). But still the system lock is getting the preference over my Custom screen lock activity.
How did you get your activity before the system lock screen?
EDIT
On a hindsight, I think my understanding of the lock screen concept was wrong. My broadcast receiver was getting the broadcast first. But what was showing before that was the system lock screen launched when SCREEN_OFF is received. Fixed that problem as of now.
But stumped by the ambiguity of home button behavior. This won't be a problem in post ICS devices as all hard buttons are discouraged.
In your LockScreenActivity, ending the validation code by finish(); kills the LockscreenActivity and thus the whole app. Instead of that, you could just launch back your main activity (or any other) like this :
startActivity(new Intent(LockScreenActivity.this, MainActivity.class));
If AOSP is in your control then you need to set the simple flag and keyguard() is gone for good.
Here is the details to do that, get into the file
"overlay/frameworks/base/packages/SystemUI/res/values/config.xml"
and search for "config_enableKeyguardService" then set the flag to false.
NO MORE keyGuard, pheww
Related
I'm targetting my application to Android O.
In my application I have a job service that shows a window over all other applications, so when it triggered it needs to show this window even when the screen is turned off & unlocked and turn it on.
I've achieved this behaviour in preior Android versions, but in Android O it doesn't work as I expected.
I've read that I need to use the flag TYPE_APPLICATION_OVERLAY and added also the permission <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW"/>in the manifest file.
So it works fine when the screen is on, but when the screen is off I've noticed that it doesn't turn the screen on, and when I turned the screen I saw that the window was created on top of other applications.
So my question is since the flags FLAG_TURN_SCREEN_ON and FLAG_SHOW_WHEN_LOCKED are deprecated in Android API 27, what are the alternatives way of doing that?
this is my current code:
private void showView()
{
if (!wakeLockAcquired)
{
wakeLock.acquire();
wakeLockAquired = true;
}
windowManager = (WindowManager)context.getSystemService(WINDOW_SERVICE);
final WindowManager.LayoutParams layoutParams = new WindowManager.LayoutParams(
ViewGroup.LayoutParams.MATCH_PARENT, ViewGroup.LayoutParams.MATCH_PARENT, 0, 0,
WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY
,
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
| WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
| WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
| WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON ,
PixelFormat.RGBA_8888);
RelativeLayout layout = buildView();
windowManager.addView(layout, layoutParams);
windowManager.updateViewLayout(layout, layoutParams);
}
Notes:
buildView is a function that returns a relativeLayout, in this function I'm adding the content dynamically (TextView, ImageView, etc...).
wakeLockAcquired is a boolean member, and it sets to false when the view is destroyed.
KeyguardManager turn on screen if attr turnScreenOn is true, so order of methods and call requestDismissKeyguard is necessary. I use this code for activity, hope it'll help:
override fun onCreate(savedInstanceState: Bundle?) {
super.onCreate(savedInstanceState)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1) {
setShowWhenLocked(true)
setTurnScreenOn(true)
val keyguardManager = getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
keyguardManager.requestDismissKeyguard(this, null)
} else {
this.window.addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD or
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED or
WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON)
}
}
OK so I've managed to solved it with some workaround and the help from the answer of #Umair.
As I said I'm displaying a view that was created in a background service using the WindowManager and with the code I've added to my question above, the view is displayed above all the other applications but not turning the screen on when Android version is Android 8.
The methods that now replaceing the Flags: FLAG_SHOW_WHEN_LOCKED FLAG_TURN_SCREEN_ON are visible to activities and not for services or for the WindowManager, and casting the context to Activity is not a good idea and will not help you :)
So What I did for now (temporary solution) is to create a transparent activity and when I'm calling to showView() method from my background service, I'm also starting the transparent activity.
In the activity - inside the onCreate method, I'm calling to the methods:
setShowWhenLocked(true)
setTurnScreenOn(true)
and when the view is destroyed, the activity will also get destroyed with the help of broadcast receiver :)
so the screen is now turned on and the view is above all the other applications.
I know that you can tell me that I can move my code that inside my service into the new activity.
The reason I did it in that way:
I'm using speech recognizer.. and when I coded it in the activity, things didn't work. I mean when the screen is locked with pattern, the activity goes to pause state and I can't get the results. so the pattern dismissed my activity..
So I decided to create a view using the window manager and it worked fine until now - when Google (Android team) decided to deprecate these flags.
So this is my solution for now.. and I hope that someone will find a better solution for this problem.
So according to android documentation these methods were deprecated so you need to use showWhenLocked or setShowWhenLocked(boolean) instead.
FLAG_TURN_SCREEN_ON
int FLAG_TURN_SCREEN_ON
This constant was deprecated in API level 27.
Use turnScreenOn or setTurnScreenOn(boolean) instead to prevent an
unintentional double life-cycle event.
Window flag: when set as a window is being added or made visible, once
the window has been shown then the system will poke the power
manager's user activity (as if the user had woken up the device) to
turn the screen on.
And FLAG_SHOW_WHEN_LOCKED
int FLAG_SHOW_WHEN_LOCKED
This constant was deprecated in API level 27.
Use showWhenLocked or setShowWhenLocked(boolean) instead to prevent an unintentional double life-cycle event.
Window flag: special flag to let windows be shown when the screen is
locked. This will let application windows take precedence over key
guard or any other lock screens. Can be used with FLAG_KEEP_SCREEN_ON
to turn screen on and display windows directly before showing the key
guard window. Can be used with FLAG_DISMISS_KEYGUARD to automatically
fully dismisss non-secure keyguards. This flag only applies to the
top-most full-screen window.
So according to documentation the reason to deprecate these methods was to avoid an unintentional double life-cycle event. You can read more about them here.
https://developer.android.com/reference/android/view/WindowManager.LayoutParams.html
Do you experience that
setShowWhenLocked(true)
setTurnScreenOn(true)
do not turn screen on any longer in Android 9? Or is it just my case?
Up to date Kotlin code with if-else for handling deprecation:
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.O) {
val keyguardManager = getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
keyguardManager.requestDismissKeyguard(this, null)
setShowWhenLocked(true)
} else {
window.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED or
WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD)
}
More explanation can be found here here.
as Dmitry Ognyov posted above - besides these:
setShowWhenLocked(true); setTurnScreenOn(true);
you need to dismiss the keyguard too keyguardManager.requestDismissKeyguard(...
I have a share button in the GCM notification. On click of the share button, I need to launch share intent. Everything works perfectly. Only problem that I'm facing is Lollipop lock screen feature. When I click share button from lock screen, my intent dialog appears below the lock screen and user has to unlock the screen to see the dialog. I want to unlock the screen programatically, when share button is clicked.
I tried with Power Manager, But all it's wakeClock flags are deprecated and WindowManager.LayoutParams.Flag_KEEP_SCREEN_ONis recommened to use. But I'm not using activity here. I'm using broadcastReciever context. and hence I cannot use getWindow()method.
I also tried with KeyguardManager. But even disableKeyguard() is deprectated.
I cannot use the Intent.ACTION_SCREEN_ON, as this should be used, if we want to perform any action after screen is unlocked.
i had used below intent to programmatically close the notification tray:
Intent it = new Intent(Intent.ACTION_CLOSE_SYSTEM_DIALOGS);
mContext.sendBroadcast(it);
Is there a similar intent, that can be broadcasted to unlock the screen
Updated Code using DevicePolicyManager:
public static void handleShareBtnClick(Context context, String message) {
GcmHelper helper = new GcmHelper();
helper.shareMessage(context, message);
if(Utility.isLollypopAndAbove()){
helper.unlockLockScreen();
}
helper.launchShareforForAlert();
}
public void unlockLockScreen(){
DevicePolicyManager devicePolicyMngr= (DevicePolicyManager) mContext.getSystemService(Context.DEVICE_POLICY_SERVICE);
ComponentName compName=new ComponentName(mContext, DeviceAdminReceiver.class);
if(!devicePolicyMngr.isAdminActive(compName))
devicePolicyMngr.removeActiveAdmin(compName);
}
Even after using DevicePolicyManager, It's not unlocking my screen
Step 1: Add below code in your activity before setContentView(R.layout.example);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON|
WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD|
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED|
WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
Step 2: Lock your mobile, then you will see activity in which you have added this code.
This will work even though your mobile is locked with pattern lock. This will work like a charm.
Closed. This question needs debugging details. It is not currently accepting answers.
Edit the question to include desired behavior, a specific problem or error, and the shortest code necessary to reproduce the problem. This will help others answer the question.
Closed 2 years ago.
Improve this question
I am developing custom lockscreen app.its working fine in below 4.0 but above 4.0,when we press home button the app stops.is there any solution for this no apps will stop when pressing home button untill unlocking the screen.(like go locker app)
Another way to develop a LockScreen App is by using Views, let me explain it.
First of all you can "disable" in some devices the System lock screen by disabling the KEYGUARD:
((KeyguardManager)getSystemService(Activity.KEYGUARD_SERVICE)).newKeyguardLock("IN").disableKeyguard();
You should put this line of code in your Service.
After that you can launch an activity every time the screen goes off:
public class AutoStart extends BroadcastReceiver {
public void onReceive(Context arg0, Intent arg1) {
if(arg1.getAction().equals("android.intent.action.SCREEN_OFF")) {
Intent localIntent = new Intent(arg0, LockScreen.class);
localIntent.addFlags(Intent.FLAG_ACTIVITY_NEW_TASK);
localIntent.addFlags(WindowManager.LayoutParams.TYPE_SYSTEM_ERROR);
arg0.startActivity(localIntent);
}
}
}
If you read the documentation for WindowManager.LayoutParams.TYPE_SYSTEM_ERROR it explains that is a type of internal system error windows, appear on top of everything they can. In multiuser systems shows only on the owning user's window.
So now you have an activity on top of everything, but a press in HOME button will exit the activity.
Here is where the Views make their appearance. You can inflate a view from a layout resource and add it to the WindowManager as a TYPE_SYSTEM_ERROR, so will be on top of everything. And since you can control when to remove this View, the best place is in onDestroy of your Activity, because pressing the HOME button will only pause your activity, and the view will still be visible.
public WindowManager winManager;
public RelativeLayout wrapperView;
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
WindowManager.LayoutParams localLayoutParams = new WindowManager.LayoutParams( WindowManager.LayoutParams.TYPE_SYSTEM_ERROR,
WindowManager.LayoutParams.FLAG_NOT_FOCUSABLE|
WindowManager.LayoutParams.FLAG_NOT_TOUCH_MODAL|
WindowManager.LayoutParams.FLAG_LAYOUT_IN_SCREEN,
PixelFormat.TRANSLUCENT);
this.winManager = ((WindowManager)getApplicationContext().getSystemService(WINDOW_SERVICE));
this.wrapperView = new RelativeLayout(getBaseContext());
getWindow().setAttributes(localLayoutParams);
View.inflate(this, R.layout.lock_screen, this.wrapperView);
this.winManager.addView(this.wrapperView, localLayoutParams);
}
public void onDestroy()
{
this.winManager.removeView(this.wrapperView);
this.wrapperView.removeAllViews();
super.onDestroy();
}
To avoid the notification bar of showing I added the flags FLAG_NOT_FOCUSABLE | FLAG_NOT_TOUCH_MODAL | FLAG_LAYOUT_IN_SCREEN to consume all pointer events.
Not forget to add these two lines to your manifest:
<uses-permission android:name="android.permission.DISABLE_KEYGUARD" />
<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />
From here you just need to add the logic of your Lock Screen app to let the user use his smartphone :)
A custom launcher is basically an app (you can make it behave like a grid, list, implement your own drag and drop etc) then, you only need to add these lines to the intent filter of the main activity, with this done, after you install your app and press the home button your app will appear in the list of available homescreens.
<category android:name="android.intent.category.HOME" />
<category android:name="android.intent.category.DEFAULT" />
What i cant find is a way to replace the lock screen, and hacks like disabling the lock screen on the phone and using an activity in a custom launcher isn't actually replacing the lockscreen ^^
You can use the below method to disable the Home key in android :
#Override
public void onAttachedToWindow() {
this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);
super.onAttachedToWindow();
}
I am developing on a Samsung Galaxy S4 5.0 and what worked for me was simply changing getWindow().setFlags(..) to getWindow().addFlags(..)
I think first of all you should ask yourself if you really want to hijack the home key. Sometimes you may want it. But I think placing the app on the Android lock screen, letting the home key act normally and letting the underlying Android lock screen take care of password-protecting the device is what you actually want in a lot of cases (unless you want to change the way this is done by default).
Bottom line, letting an app be displayed on the Android lock screen comes pretty close to writing your own custom lock screen. And is decidedly easier since you don't have to manage passwords yourself. Not to mention it's safer and more reliable since you don't hijack the home key.
I did it like this and it works very well. You can see the details here:
show web site on Android lock screen
The question is about displaying a website on the lock screen, since that's what I was interested in, but the answer is more general, it works with any app.
You can see here an app that's on Google Play and has been written like this:
https://play.google.com/store/apps/details?id=com.a50webs.intelnav.worldtime
A few years ago, I wrote an alarm app that worked on Android 2, and I'm now trying to upgrade it to work on Android 4. Specifically, on the Samsung Galaxy S4.
On Android 2, if the phone was sleeping, it would wake the phone up and display a "Snooze or Dismiss" screen over the lock screen.
On Android 4, it wakes the phone up, but you have to unlock it, then open the notifications area, then click the alarm's notification, before you can hit "Dismiss."
I have always been using this code to do the waking:
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
| WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
| WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
| WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
I have read 8 different stackoverflow questions on this matter. Most of them give the code above, which worked for me years ago in Android 2 but doesn't work in Android 4. But none of them have helped me solve this problem. Here are the questions that I read and tried:
Android: remove or disable programmatically the Lock Screen on Samsung Galaxy S2 device
How to display a fullscreen TYPE_SYSTEM_ALERT window?
How do I create an Activity that is visible on top of the lock screen
How to start a dialog (like alarm dimiss /snooze) that can be clicked without unlocking the screen
Android activity over default lock screen
android device locked, yet want alarm to sound and dialog to appear
Android dialog over lock screen
Show dialog with touch events over lockscreen in Android 2.3
Does anyone have any ideas about what's changed in Android 4 that may have caused this?
EDIT: Here is one of the simplest examples I've seen of an alarm dialog that doesn't come up "minimized." It does not, as written, appear over the lockscreen, but you can fix that with WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
http://wptrafficanalyzer.in/blog/setting-up-alarm-using-alarmmanager-and-waking-up-screen-and-unlocking-keypad-on-alarm-goes-off-in-android/
It's written with a FragmentActivity and a DialogFragment, but it still works as an Activity. It uses an AlertDialog.Builder to make the dialog, and if you try to do it with an XML layout, it won't work. Why?
I figured it out, and the answer was very different from what I expected.
This piece of code was included in the alarm clock sample from Android 2, in the AlarmAlert.java Activity:
#Override
protected void onStop() {
super.onStop();
// Don't hang around.
finish();
}
For reference, you can see the file from the example code in Git's past right here, containing the above onStop function. It never caused a problem in Android 2.
But in Android 4, if the phone was off, this onStop would fire right before the phone woke up, effectively "minimizing" the Activity. Once I removed this function, it immediately worked again.
But I wonder, is this the problem that other people like #radley and #Guardanis are getting? It seems unlikely, but please let me know if this fixes your problems too.
If you're visiting this answer in the future, and you're getting this problem, what I would try is:
Take out any onStop functions.
Add this code to the Activity:
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
| WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
| WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
| WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON);
Make sure you're using a full screen theme, and not a dialog theme.
This didn't make a difference for me, but you could try setting showOnLockScreen explicitly in the manifest: <activity android:name="com.example.MyActivity" android:showOnLockScreen="true"/>
A second thing that didn't make a difference for me but you might try is adding the flag WindowManager.LayoutParams.FLAG_FULLSCREEN
I hope this helps other people!
In Kotlin,
For Api level 28 or less, you can simply add below method in your activity that needs to be opened:
override fun onAttachedToWindow() {
super.onAttachedToWindow()
toBeShownOnLockScreen()
}
private fun toBeShownOnLockScreen() {
window.addFlags(
WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
or WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
)
if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.O_MR1) {
setTurnScreenOn(true)
setShowWhenLocked(true)
} else {
window.addFlags(
WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
or WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
)
}
}
And to make it work on Android Pie and above, in additional to above step, we need to set in AndroidManifest as well:
<activity
android:name=".view.activity.LockScreenActivity"
android:showOnLockScreen="true"
android:showWhenLocked="true"
android:turnScreenOn="true" />
I have tested this code from Api level 21 to 29, and works like charm!
Not sure if this is the problem in all cases, but the documentation on ShowWhenLocked says it applies only to the top-most full-screen window. I had a window themed as a dialog which was not working, but it worked fine once I changed it to a regular full-screen window.
One of the questions you linked to has an answer that appeared to solve this issue for me.
This is the code I am using which appears to be working:
#Override
public void onAttachedToWindow() {
Window window = getWindow();
window.addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON
| WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED
| WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON
| WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD
| WindowManager.LayoutParams.FLAG_FULLSCREEN);
super.onAttachedToWindow();
}
I'm also explicitly declaring this in the activity definition in the manifest:
<activity
android:name="com.example.MyActivity"
android:label="#string/app_name"
android:showOnLockScreen="true"
>
Android activity over default lock screen
Right - So I have been struggling with this one recently but with a 5.0.2 Galaxy Tab A. Unsurprisingly what works on every other device does not work on Samsung (this has been the case since the first Samsung Galaxy device, they break something new each release!)
The general solution for showing an Activity over the lock screen for most devices is
//wake up device and show even when on lock screen
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD |
WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED |
WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON |
WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON |
WindowManager.LayoutParams.FLAG_FULLSCREEN);
However this does not work for samsung devices. Removing FLAG_DISMISS_KEYGUARD however does this trick.
Looking at the docs for this flag we have
Window flag: when set the window will cause the keyguard to be dismissed, only if it is not a secure lock keyguard. Because such a keyguard is not needed for security, it will never re-appear if the user navigates to another window (in contrast to FLAG_SHOW_WHEN_LOCKED, which will only temporarily hide both secure and non-secure keyguards but ensure they reappear when the user moves to another UI that doesn't hide them). If the keyguard is currently active and is secure (requires an unlock pattern) than the user will still need to confirm it before seeing this window, unless FLAG_SHOW_WHEN_LOCKED has also been set.
and for FLAG_SHOW_WHEN_LOCKED we have
Window flag: special flag to let windows be shown when the screen is
locked. This will let application windows take precedence over key
guard or any other lock screens. Can be used with FLAG_KEEP_SCREEN_ON
to turn screen on and display windows directly before showing the key
guard window. Can be used with FLAG_DISMISS_KEYGUARD to automatically
fully dismisss non-secure keyguards. This flag only applies to the
top-most full-screen window.
You can see they can be used together but it seems samsung will not bother with FLAG_SHOW_WHEN_LOCKED if the device is locked and FLAG_DISMISS_KEYGUARD is present. My app requires a lock screen to be setup so removing the dismiss keyguard flag actually allows me to show full screen Activities over the lock screen. Yay for me, nay for samsung.
i need to dismiss the default lock screen on some cases . it is possible using KeyguardManager.KeyguardLock , but it's deprecated and might not be available on the new android v4 version (ICS) .
instead , here android docs i read that i should use "Use FLAG_DISMISS_KEYGUARD and/or FLAG_SHOW_WHEN_LOCKED "
so I've tried playing with them , but no matter what i try , after closing the activity that use those flags , i get back to the default lock screen , even if it's not the secure one .
what is going on , and how should i fix it?
I've also read that there are some workarounds , by replacing the launcher application , but this is a weird fix , and requires the user's intervention , even though the application is not really a launcher application , and i'm not sure how i would
such a feature might even be used for replacing the lock screen with your own customized lock screen
Check our issue 8778, which seems to be similar to what you are facing. The FLAG_DISMISS_KEYGUARD constant will ONLY work if you are using an Activity, it must not be PixelFormat.TRANSLUCENT, and it is forcing itself to be full screen, hiding system decoration like the status bar. The KeyguardManager API is deprecated, but it still works on Android 4.0 ICS and it is arguably your best bet at disabling the lock screen reliably and from any part of your code (even a background Service).
In case somebody needs Kotlin code that's up to date:
if (Build.VERSION.SDK_INT > Build.VERSION_CODES.O) {
val keyguardManager = getSystemService(Context.KEYGUARD_SERVICE) as KeyguardManager
keyguardManager.requestDismissKeyguard(this, null)
setShowWhenLocked(true)
} else {
window.addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED or
WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD)
}
And if you need a longer explanation on keyguard flags, check here.