How to disable Home and other system buttons in Android?

Question

I need to disable Home and other system buttons in my Android application.

Example: MX Player (see at Google Play) - you can press "lock" icon at player screen and it locks all hardware and software system buttons.

It works fine WITHOUT ROOTING.

I tested it on some devices with different Android versions. I tried to disassemble Kids Lock (plugin) but has no clue how it works yet.

I need same solution like the Kids Lock (plugin) for MX Player: - disable Home, Back and all other system buttons.

Any suggestions?

Answer 1

First of, please think long and hard if you really want to disable the Home button or any other button for that matter (e.g. the Back button), this is not something that should be done (at least most of the times, this is a bad design). I can speak only for myself, but if I downloaded an app that doesn't let me do something like clicking an OS button, the next thing I do is uninstall that app and leave a very bad review. I also believe that your app will not be featured on the App Store.

Now...

Notice that MX Player is asking permission to draw on top of other applications:
Since you cannot override the Home button on Android device (at least no in the latest OS versions). MX Player draws itself on top of your launcher when you "lock" the app and clicks on the Home button.
To see an example of that is a bit more simple and straight forward to understand, you can see the Facebook Messenger App.

As I was asked to provide some more info about MX Player Status Bar and Navigation Bar "overriding", I'm editing my answer to include these topics too.

First thing first, MX Player is using Immersive Full-Screen Mode (DevBytes Video) on KitKat.
Android 4.4 (API Level 19) introduces a new SYSTEM_UI_FLAG_IMMERSIVE flag for setSystemUiVisibility() that lets your app go truly "full screen." This flag, when combined with the SYSTEM_UI_FLAG_HIDE_NAVIGATION and SYSTEM_UI_FLAG_FULLSCREEN flags, hides the navigation and status bars and lets your app capture all touch events on the screen.

When immersive full-screen mode is enabled, your activity continues to receive all touch events. The user can reveal the system bars with an inward swipe along the region where the system bars normally appear. This clears the SYSTEM_UI_FLAG_HIDE_NAVIGATION flag (and the SYSTEM_UI_FLAG_FULLSCREEN flag, if applied) so the system bars become visible. This also triggers your View.OnSystemUiVisibilityChangeListener, if set. However, if you'd like the system bars to automatically hide again after a few moments, you can instead use the SYSTEM_UI_FLAG_IMMERSIVE_STICKY flag. Note that the "sticky" version of the flag doesn't trigger any listeners, as system bars temporarily shown in this mode are in a transient state.

Second: Hiding the Status Bar
Third: Hiding the Navigation Bar
Please note that although using immersive full screen is only for KitKat, hiding the Status Bar and Navigation Bar is not only for KitKat.

I don't have much to say about the 2nd and 3rd, You get the idea I believe, it's a fast read in any case. Just make sure you pay close attention to View.OnSystemUiVisibilityChangeListener.

I added a Gist that explains what I meant, it's not complete and needs some fixing but you'll get the idea. https://gist.github.com/Epsiloni/8303531

Good luck implementing this, and have fun!

Answer 2

You can use Android-HomeKey-Locker to disable HOME KEY and other system keys(such as BACK KEY and MENU KEY)

Hope this will help you in your application. Thanks.

Answer 3

I followed the shaobin0604's answer and I finally managed to lock the HOME button, by adding:

<uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" />

to AndroidManifest.xml All you have to do is to copy HomeKeyLocker.java from shaobin's lib to your project and implement it like in shaobin's example. BTW: My AVD's Android version is Android 4.0.3.

Answer 4

You can disable the home and recents button Android 5.0, using the screen pinning feature mentioned here:

Android 5.0 introduces a new screen pinning API that lets you temporarily restrict users from leaving your task or being interrupted by notifications. This could be used, for example, if you are developing an education app to support high stakes assessment requirements on Android, or a single-purpose or kiosk application. Once your app activates screen pinning, users cannot see notifications, access other apps, or return to the home screen, until your app exits the mode.

You can lock the device down to be a kiosk. The navigation bar is not hidden, but the home and recents buttons can be either removed or disabled depending how you activate the mode. I wrote some information after testing this feature here.

Answer 5

Just a guess, but I think with the SYSTEM_ALERT_WINDOW permission (displayed as "Draw over other apps", see here) it could be possible: display your app as a fullscreen, system alert type window. This way it will hide any other apps, even the homescreen so if you press Home, it won't really be disabled, just without any visible effect.

MX Player has this permission declared, and Facebook Messenger has it too for displaying "chat heads" over anything - so it might be the solution.

Update (added from my comments): Next, use SYSTEM_UI_FLAG_HIDE_NAVIGATION in conjunction with capturing touch events/using OnSystemUiVisibilityChangeListener to override the default behaviour (navbar appearing on touch). Also, since you said exit immersive gesture does not work, you could try setting SYSTEM_UI_FLAG_IMMERSIVE_STICKY too (with SYSTEM_UI_FLAG_FULLSCREEN and SYSTEM_UI_FLAG_HIDE_NAVIGATION).

Answer 6

It used to be possible to disable the Home button, but now it isn't. It's due to malicious software that would trap the user.

You can see more detailes here: Disable Home button in Android 4.0+

Finally, the Back button can be disabled, as you can see in this other question: Disable back button in android

Answer 7

If you target android 5.0 and above. You could use:

Activity.startLockTask()

Answer 8

First create a method :

public void hideNavigationBar() {
        final View decorView = this.getWindow().getDecorView();
        final int uiOptions =
                View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        | View.SYSTEM_UI_FLAG_LAYOUT_STABLE;

        Timer timer = new Timer();
        TimerTask task = new TimerTask() {
            @Override
            public void run() {
                YourActivityName.this.runOnUiThread(new Runnable() {
                    @Override
                    public void run() {
                        decorView.setSystemUiVisibility(uiOptions);

                    }
                });
            }
        };

        timer.scheduleAtFixedRate(task, 1, 2);

    }

Then you call it on onCreate() method of your activity. Call it again on the onResume() method. Then you may add another method in your activity like this:

@Override
    public void onWindowFocusChanged(boolean hasFocus) {
        super.onWindowFocusChanged(hasFocus);
        hideNavigationBar();
    }

That will be it. Do remember it will lock the screen till the next time user touches the screen, in Timer class you can change the delay and it will allow you change things for that instance.Then it will lock the screen again.

Answer 9

I too was searching for this for sometime, and finally was able to do it as I needed, ie Navigation Bar is inaccessible, status bar is inaccessible, even if you long press power button, neither the power menu nor navigation buttons are shown. Thanks to @Assaf Gamliel , his answer took me to the right path. I followed this tutorial with some slight modifications. While specifying Type, I specified WindowManager.LayoutParams.TYPE_SYSTEM_ERROR instead of WindowManager.LayoutParams.TYPE_PHONE, else our "overlay" won't hide the system bars. You can play around with the Flags, Height, Width etc so that it'll behave as you want it to.

Answer 10

i dont know how to diable home button. as long as my knowledge i got folowing link.

refer the link:- http://developer.android.com/reference/android/view/KeyEvent.html#KEYCODE_HOME

Key code constant: Home key. This key is handled by the framework and is never delivered to applications.

But,we can diable back button. hope following code helps you out.

@Override
public void onBackPressed() {
    //return nothing 
    return;
}

Answer 11

Refreshing an old topic. I was able to achieve that my activity does not fold when the home button (physical or virtual) is pressed. Here is my code for activity onCreate() method:

super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_alarm_screen);
        context = getApplicationContext();
        int windowType;
        if (Build.VERSION.SDK_INT>=26) windowType = WindowManager.LayoutParams.TYPE_APPLICATION_OVERLAY;
        else windowType = WindowManager.LayoutParams.TYPE_TOAST;
        final WindowManager.LayoutParams params = new WindowManager.LayoutParams(
                windowType,
                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,
                PixelFormat.TRANSLUCENT
        );
        wm = (WindowManager) getApplicationContext()
                .getSystemService(Context.WINDOW_SERVICE);

        mTopView = (ViewGroup) getLayoutInflater().inflate(R.layout.activity_alarm_screen, null);
        getWindow().setAttributes(params);
        //Set up your views here
        testView = mTopView.findViewById(R.id.test);
        wm.addView(mTopView, params);

On API 26 and abovem you need to get screen overlay permission from the user. Tested on Android 7 and 8.

Answer 12

You can't disable Home button from ICS onwords but can disable other buttons as follows

@Override
public boolean dispatchKeyEvent(KeyEvent keyEvent){
   return true;
}

Answer 13

Post ICS i.e. Android 4+, the overriding of the HomeButton has been removed for security reasons, to enable the user exit in case the application turns out to be a malware.

Plus, it is not a really good practice to not let the user navigate away from the application. But, since you are making a lock screen application, what you can do is declare the activity as a Launcher , so that when the HomeButton is pressed it will simply restart your application and remain there itself (the users would notice nothing but a slight flicker in the screen).

You can go through the following link:

http://dharmendra4android.blogspot.in/2012/05/override-home-button-in-android.html

Answer 14

Frankly it is not possible to disable the home button at least on new api levels , that is from 4.0 onwards. It is also not advisable to do that. You can however, block the back button by overriding the

public void onBackPressed() {
    // do not call super onBackPressed.
}

in order to override the home button, you could use a timer for example, and after every time check if the main screen is your screen or not, or your package is on top or not, (i am sure you will get links to it), and display your activity using the flag single_top.

That way , even if the home button is pressed you will be able to bring your app to the top.

Also make sure that the app has a way to exit, because such kind of apps can really be annoying and should never be developed.

Happy coding.

P.S: It is not possible to intercept the home event, when the home button is pressed.

You can use on attach to window methods and also keyguard methods, but not for api levels from 4.0 onwards.

Answer 15

Using rotation causes an exception, So I've fixed my activity using this:

HomeKeyLocker locker;

@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);

    requestWindowFeature(Window.FEATURE_NO_TITLE);
    setContentView(R.layout.activity_splash);

    locker = new HomeKeyLocker();               
    locker.lock(this);
}

@Override
protected void onSaveInstanceState(Bundle savedInstanceState) {
    super.onSaveInstanceState(savedInstanceState);
    locker.unlock();
}

@Override
public void onConfigurationChanged(Configuration config) {
    super.onConfigurationChanged(config);
    locker.lock(this);
}

You will need to use the @Lê Quang Duy suggestion.

Answer 16

I'm working on an application that needs to lock the tablet just for application. First I put my app as MainLauncher, then I lock the taskbar using an AndroidView. Finally I block the tablet. It is not a feature that I indicate to use across multiple tablet models, since each device model has a feature to block it.

But overall it works for everyone. You can use the commands

Java.Lang.Runtime.GetRuntime().Exec("su -c sed -i '/VOLUME_UP/s/^# //g' /system/usr/keylayout/Generic.kl");

as an example to disable the buttons. But everything is based on changing the system files, inside the folder "/ system / usr / keylayout / ...". NOTE: Only works on rooted devices.

Another way I'm trying though still developing is using StreamWrite and StreamReader to access the RootDirectory and rewrite the whole file to disable and enable the buttons.

Hope this helps.

And any questions remain available.

Answer 17

For anyone looking to completely remove the soft-nav on a rooted (or custom ROM) android device, you can modify the build.prop text file within the system folder.

Set the following variable/value:

gemu.hw.mainkeys=1

This is what vendors use to disable the soft nav, when they have physical buttons.

Answer 18

Sorry for answering after 2-3 years. but you can hide activity of all system buttons. Just check this my answers How to disable virtual home button in any activity?.