I found a trick on a galaxy tab for use it as a kiosk
according to the developer guide of Samsung
You can ask your app to be over the lock system and ask the return button to go back to a start activity/view of your app.
I done this for a web View app
@Override
public void onBackPressed() {
//here asking to go back to home page
mWebView.loadUrl(mHomepageUrl);
}
for asking to stay up from the lock system, on the onCreate method :
getWindow().addFlags(WindowManager.LayoutParams.FLAG_DISMISS_KEYGUARD);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_SHOW_WHEN_LOCKED);
and then when you click on the power button twice , you found back your application , and only the back button is active on the status bar
So the only way is to reboot the tablet (and so you can use the classic lock system with a code to open tablet)
Can be useful if the power button is not accible by visitor , or if your are the only one who have the unlock code
com.android.systemui
process - not very elegant but that hides / kills the bar. – Arsis