I am developing an app that locks the screen for some time, just like parental control apps do when the screen time runs out. However, I do not really know how they work. I suppose they don't use lockNow because there is that message that shows up telling you that the time has run out. I also don't think they use overlays, because the phone is supposed to detect the use of overlays. So does anybody know what kind of function is used? Also for my app I want to add a button that ends the screen lock, so I am looking for a suitable way to achieve that.
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I want to make app with which after running, within the app, I can see my phone screen and want to be able to draw or mark certain area. As I don't have much experience. Can anyone help?
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.
Is there a way to display text on lock screen? Like the information about unread SMS messages or like that Music Player on lock screen with Play/Pause buttons.
Thanks
Yes and no. Their is no public API to create or modify the lock screen. Whoever built the OS version on your device created your lock screen. Some of the manufacturers or carriers have added additional things to the lock screen. I've seen some that tie in to the music app, HTC sense has a somewhat customizable lock screen. So if you were willing to create your own rom and flash it to your device you could write your own lockscreen. Short of that the best you can do is write an app that the system thinks is an alternate home screen that has some kind of lock mechanism before the actual home is displayed. Then you set your device not to use a lock screen(so that it won't show both) This is not a great solution however, there are bound to be more ways to access the device if you use a "fake" lock screen like that so if security is an issue I wouldn't mess with it at all.
You might be able to find one of these "fake" lock screens on the market that suites your needs or you could create one that is exactly what you want. You could also search around on XDA for a rom that works with your device, 3rd party roms may be more likely to have the features your looking for on the lock screen.
If you end up making a pretend lock screen by using the home replacement method I strongly suggest you do not distribute something like that on the market. It is insecure and the users are unlikely to realize that there is a difference between that and a legit lock screen. Plus there is no guarantee that this method doesn't get broken at some point.
I'm working on my first android app. So far I have an activity that reacts to clicks on the hardware volume controls. That's was easy to do, but I'm wondering if there is a way to make it so the app responds to these events from the hardware buttons even while the phone is locked?
I'm really looking for a confirmation of whether or not this can be done. If someone could confirm and give me the general idea of how to do it that would be awesome.
I have not done exactly this but I believe that if you put
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
in your Activity onCreate() you will be able to do what you want even if the screen is locked.
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).