Android activity over default lock screen

How can I display an Activity or Dialog to be visible over the lock screen?

I have already tried displaying my lock activity when screen turns on by setting various window type in Activity.onCreate() method:

TYPE_PRIORITY_PHONE
TYPE_SYSTEM_ALERT
TYPE_KEYGUARD

and others together with SYSTEM_ALERT_WINDOW and INTERNAL_SYSTEM_WINDOW permissions.

My activity is visible after I unlock the device.

UPDATE:

I actually already managed to display my own Activity instead of default lock screen. It work perfectly unless you use HOME button.

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);

try using this flags to disable lock screen when the activity is started.

After API level 17 you can use

<activity
        android:name=".yourActivityName"
        android:showOnLockScreen="true"
        android:screenOrientation="sensorPortrait" >

showOnLockScreen like in the example...

Don't go for activity, because android will not show lock screen behind your activity for security reason, so use service instead of Activity.

Below is my code in onStartCommand of my service.

WindowManager mWindowManager = (WindowManager) getSystemService(WINDOW_SERVICE);

View mView = mInflater.inflate(R.layout.score, null);

WindowManager.LayoutParams mLayoutParams = new WindowManager.LayoutParams(
ViewGroup.LayoutParams.WRAP_CONTENT,
ViewGroup.LayoutParams.WRAP_CONTENT, 0, 0,
WindowManager.LayoutParams.TYPE_SYSTEM_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);

mWindowManager.addView(mView, mLayoutParams);

And add <uses-permission android:name="android.permission.SYSTEM_ALERT_WINDOW" /> to manifest

Use this in onCreate method

getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);  
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_TURN_SCREEN_ON); 
// This line should be before setContentView.. 	    
setContentView(......);

Hope this will work Thanks

You can use code in any of answers here that you think it's working. Then to prevent HOME button to work, change TYPE_SYSTEM_ALERT or TYPE_SYSTEM_OVERLAY (depends on what you currently use) to TYPE_SYSTEM_ERROR:

params = new WindowManager.LayoutParams(
	WindowManager.LayoutParams.MATCH_PARENT,
	WindowManager.LayoutParams.MATCH_PARENT,
	WindowManager.LayoutParams.TYPE_SYSTEM_ERROR,
	WindowManager.LayoutParams.FLAG_FULLSCREEN | 
    WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED | 
    WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD,
	PixelFormat.TRANSLUCENT
);
params.gravity = Gravity.TOP;
mOverlay = (RelativeLayout) inflater.inflate(R.layout.main, (ViewGroup) null);
mWindowManager = (WindowManager) context.getSystemService(Context.WINDOW_SERVICE);
mWindowManager.addView(mOverlay, params);