I'm developing a home replacement application for kids. The user can't exit from the app (for example to open another application such as Settings) without a password.
What can I do to obtain this behavior?
I guess:
I should block the back button (done).
I should block the "recent apps" button (done but it's unstable)
I should block the access to the notification bar (is that possible? How?)
...?
I have spent the last 6 months developing this kind of application. The sad answer is, none of the above is fully possible. Android does not allow an application to meddle with things like notification bar, HOME Button or factory-reset resistance.
The only way to ensure you will be able to control all these things is to have a system signature, but it is only granted by the manufacturer for a selected phone model.
You can also try rooting the phone and meddling with the system config files directly, but it is rather dangerous.
You can hide the notification bar by using
getWindow().setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN,
WindowManager.LayoutParams.FLAG_FULLSCREEN);
With these the activity goes on fullscreen and should hide the notification bar.
However this works only for activity where you use it, so if you want to make it work for he entire app i suggeste you to put this inside the onCreate of a class that extends Activity and then make all of your activity extends this class.
Related
Is there any programming tricks that makes your application unclosable?
For example: You touch the back or the home button, but they don't do anything.
Or at least is there a way that your application blocks some applications to open?
I don't think you can stop user from moving your application to background unless it's some kiosk mode app. And the method to do that is to become device administrator and override all possible callback methods - home, back, settings, notification area etc.
If you just want to prevent your app from getting closed due to user activity you can show a persistent notification. This will allow you app to run in background even if user presses home button.
Make a launcher/Home screen app:
When users click the home button, your app will show.
You control ALL apps that can be started
On devices running android lolipop, you can use the screen pinning option available in your ROM.
NOTE: This is ROM feature, you don't have to do anything in your app.
See this great article about it.
yes its to get set the on backpressed method to.
moveTaskToBack(true);
finish();
Are you trying to hack in android OS ? Let me tell you that android apps are sandboxed, which isolates your app data and code execution from other apps.
I am working on an application in which user should be able to use only one application,
he should not be able to switch application using HOME button,
the app. should be closed only when user presses the close button..
I have managed to override return button, don't know how to disable HOME button.
This is not possible to disable the Home Button in android When application is in the background because it might some application always disable the home button if it's possible. So this is the reason developer can't disable the home button when app in background. But In the Activity, you can intercept the home button.
In Activity you can disable the Home key in android. It work till Android 3.x only.
#Override
public void onAttachedToWindow() {
this.getWindow().setType(WindowManager.LayoutParams.TYPE_KEYGUARD);
super.onAttachedToWindow();
}
TGMCians is right.
Android will not let an activity and its services run completely alone on your device.
Using Override you can capture button clicks (home, back and menu) when your activity is in the foreground. If an activity/service has full control from the background you would not be able to switch for an incoming sms, e-mails, phone calls, etc either.
Personally I think its dangerous to override the home and back button together, if the activity hangs at some point, you can not get out of the app unless you restart the phone.
Personally, I do override the back key for exit, or return to main screen events, but leave the home button alone.
This is not possible using code at all on iOS, ever.
One usage of HOME button is for emergency situation.
Any house, apartment ... they all have an emergency method, like emergency door (exit), glass breaker (axe, bat ...); it saves life.
Similarly, on Android/iOS phone, HOME button saves users' lives (well, kind of). If HOME button is dead, the phone is considered dead as well as required an instant reboot for refresh. The button was designed for such a purpose, so that developers can't messed-up with everything.
Personally, I'm kinda of being thankful for Android/iOS framework team and whoever thought of this situation on HOME button. It saves my development so many times. I suggest you should think and consider the worst case possible if HOME button is not working in your app; for example, app fails to function as normal, HOME is disabled, so how to back to HOME screen, how to switch to other apps?...
The code provided by TGMCians is not working on 4.0+.
In case, you are working on Android framework, such as building ROMs, building frameworks for manufacturers, ... grep the source code with KEY_HOME and trace inner-depth to find how it works and disable it.
actually, it is possible to block the home button using the next methods:
use of security holes, at least on old android versions. this is done on some locker apps. i think some still work even on newer android versions, but it's a risk and it might be buggy on some devices. i know that "widgetLocker" and "Picture Password Lockscreen" try out those holes. i'm not sure how well they work now with them. best solution of becoming a lockscreen is #2 .
make your app a launcher app, which will handle the home button (user must confirm it of course). an example of such an app is "MagicLocker" , and in fact any launcher app...
using a rooted device. i have no idea how to do it, but i think it's very possible.
not quite a blocking method, but you could have your app full screen and on top (using the TYPE_SYSTEM_ALERT window layout type) , so home button won't be captured, but the user won't see what's going on behind your app. the downside is that any other button won't be captured by your app, since it's not really on the foreground.
i just want to know how can i detect if the user opens an app so an activity of mine launches as well.
For example, the user opens the sms app and right after a kind of lockscreen appears.
You can create a service which will run int the background and you can use this API to determine which activity is visible. That's how many app lock works.
As far as I understand the Android system, it is not possible unless you are making a custom firmware.
I'm developing a presentation style application for HoneyComb Tablets. At one stage the tablet may be passed around a room for people to interact with. If possible I would like to prevent malicious users from navigating away from the current activity.
So far I have overwritten the onBackPressed() to prevent finishing the activity but users can still press the other buttons on the status bar and also leave the app via notifications that pop up.
Any suggestions or possible solutions?
Thanks
1. Make your activity full screen.
2 Use an alarmManager to trigger your activity from a service on a regular interval say 2or3 second (only if your activity is not foreground). For this use a boolean variable and store it using sharedPreference. this value will be true in onReume and false in onPause or in onStop or in onDestroy. And then only start your activity from your service if the boolean variable is false. Now if your user will press the Home button then AlaramManager kick start your activiy again.
3 Make a special button for finishing your service and activity and for cancel the alarmManager.
As far as I know there is no way to capture the home button press, so this is not possible. Not to mention, it would be a bad ui design decision by the dev team. The home button is there so every Android user has a standard way to exit apps. There would be some extremely malicious apps if there was a way to make the user unable to exit an app.
I'm developing a similar application that runs in a "kiosk" fashion for retail stores. When the application launches, it programmatically hides the system bar so you cannot exit. The system bar is restored when the tablet is rebooted. It requires root/su however.
The question I'm about to ask may seem dangerous for the user, so here's the story before the question:
I'm working in a compagny that tries to sell Galaxy Tabs to schools (children under 10). So, I've been asked to develop an application that starts on boot showing a login screen. The child HAS to log in before he's allowed to use the tablet (just like logging in a computer).
My application starts on boot, shows the login screen, all buttons are blocked (the kid must not be able to use the tablet before the application lets him) except the home button.
fortunately, it seems impossible to block the home button.
I've been trying to rebring the application to front when onpause/onstop is called, this kind of hacks.
So my question is : Can I prevent an user to quit my application until I let him do so?
I know this sounds like a virus, I'm not really happy to be looking for this kind of solution either.
You have to build a custom Home screen, and then set it as the default Home application.
EDIT: see more on this previously asked question (at How can I create a custom home-screen replacement application for Android?). You can just make your authorization the default Home application, then when they log in it forwards to the regular Home screen. If they hit the home button your app gets called, can check if they have logged in and if they have will just send them to the regular home screen.