Is it possible to Display Information on the lock screen from an Android application.
I came across a few Apps which allow you to display Email and Calendar information on the screen but could not find which API to use for achieving the same.
Android 4.2 supports app widgets on the lockscreen.
according to the app you've mentioned (which has very poor description and quite low rating) , i suspect they disable the keyguard (the default lock screen) each time they get the event of power off (or on) .
maybe the activity that they are using has a transparent background and is above the normal lock screen .
there are many similar apps , such as "widget Locker" ,"magic Locker" and "quick Launch" , all do about the same thing to replace the keyguard . most of them also have the ability to replace the launcher (but will still show the launcher of the user, of course) , for smoother experience .
does the screenshot belong to the app you've mentioned , or to something you wish to achieve ?
You can learn how it can be done if you look at the sources of open source project contact owner that adds a message to the lock screen, too.
Related
Is there a way to change the lock screen in Android programmatically?
If yes, is it possible to create an animation within that view?
Is there a way to change the lock screen in Android programmatically?
No, because there is only one lock screen. On Android 4.2, the user can add app widgets to the lock screen, if the user chooses. You can elect to create an app widget that can be added to the lock screen.
If yes, is it possible to create an animation within that view?
Generally, no. App widgets are not normally animated.
android doesn't officially supports it with a nice API , but there are some solutions for this problem . the best one that i can think of and that will work perfectly on all devices and android versions is this :
you can make an app that functions as a launcher , and ask the user to disable the lock screen.
this way , when the screen is turned off&on , your app will be able to be shown and do whatever it needs .
each time the app is being unlocked , it will send the intent of the home button to the real launcher the user has chosen .
of course , there are other solutions , but as i've tried , all of them have some kind of problem on some android devices and versions . they work by listening to the power off intent , and block the home button by using a flaw they've found in the android source code . you can never assume that it will work on all devices and android versions .
example of such apps are "widgetLocker" and "Picture Password Lockscreen"
I haven't found a definite answer to this yet. Lots of apps let you build/install custom lock screens without root, etc. It's just like installing an app. I found this in the dev guide: http://developer.android.com/reference/android/view/WindowManager.LayoutParams.html#FLAG_SHOW_WHEN_LOCKED
I assume that while this is running it would run just like any other app. But how would I "release" it to let the user get to their home screen? And do I need to handle things like incoming phone calls?
You can't (at least if you follow the rules) replace the secure lock screen. You can have a lock-screen like activity that will show up when the phone is locked. Use FLAG_SHOW_WHEN_LOCKED, but notice that your activity cannot be transparent - i.e. it cannot be a dialog.
I was hoping to make an app which dimmed the soft buttons to dots on the Galaxy Nexus, using the code from this answer. For completeness, this is the code:
getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_LOW_PROFILE);
Here's the question, is it possible for the app to make this setting system-wide rather than just while the app has focus? So ideally the app would run in the background and would keep View.SYSTEM_UI_FLAG_LOW_PROFILE as the default as long as it's running, for any and every app that you open (unless that app specifically overrides it, I suppose). Is this possible or does this fall outside the realm of what an Android app has permission to do?
A sample use case is this: I use the "Screen Filter" app to reduce brightness a lot for nighttime ebook reading or misc app usage, but the soft buttons are still very bright and distracting, so I wanted to make an app that would dim the soft buttons system-wide while running (like how "Screen Brightness" reduces screen brightness system-wide while running) so this wouldn't be a problem.
As CommonsWare states, it's not possible for an application to change this setting. It's an Activity based setting, that must be set for every single Activity, if you want to make it fullscreen, hide the soft keys, etc.
It's also worth pointing out that you should probably refrain from using it in all your application activities. It's really only meant for games, video players and other applications that need to enter this "low profile" state.
Feel free to accept CommonsWare's answer - I just thought I'd give you a bit of background info on the subject.
is it possible for the app to make this setting system-wide rather than just while the app has focus?
No.
Let me begin by saying that, yes, I know that the stock Android lock screen can not be programatically replaced without rooting.
Now that that's over with, I want to make an app that contains a custom 'lock' mechanism. There are apps out there that emulate this functionality, namely LockGo. This allows a user to view information from widgets on a 'lock screen' and emulates the slide-to-unlock functionality (or whack-a-mole if the user wants to install that plugin).
Does anyone know what mechanism or Android API functionality they may have used to do this? Is it as simple as hooking into the power button to launch an activity, such as in the link below?
How to hook into the Power button in Android?
Any insight to this would be appreciated.
I've found out while researching this that, while there is currently no way to replace the stock security or keyguard lock (which I knew), it is possible to show an Activity on top of the lock using the following code in the setup for that Activity:
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
This can be used with any logic needed to create a faux lock to show screens on top of the system lock(s), though the lock will still be in tact and the user will need to enter the lock to get into the device.
Today I am looking for a way to mimic the behavior I know from my HTC Hero's lock screen: the calendar and alarm clock can put text & drawables there to inform about an upcoming event or an expired alarm. The lock screen remains there in that it must be dragged down to dismiss the shown event and there might also be a Snooze button.
But, first question: is this default Android stuff or HTC Sense specific only??
Second question: If it is a common Android thing, why can't I find anything in Google's Android documentation for the topics "lockscreen" or "lock screen" that comes close to my question? Where's the API for it?
My problem is: I want to inform the user immediately - even if I try a standard notification, the user with a locked screen will have to unlock it and drag down the notifications list to see & clear what's going on. sigh Putting an endlessly playing notification sound there is a hassle as it takes at least two swipes down to stop the sound playing!
Any hints on this?
Thanks!
is this default Android stuff or HTC
Sense specific only?
It is HTC Sense only. You cannot modify the lock screen of the device from SDK code -- only via firmware modifications. Sorry!
It's kind of o long way around the problem...
but the wallpaper is shown on then lockscreen. so you clould write a custom wallpaper to display your info on the lockscreen. (i think).