Seems it is a security feature of Android firmware and there is no way to disable it from inside of 3rd-party application.
Without the notification, an app can take over the screen and emulate parts of the system that you could happen to think are part of the system.
You can see a really good explanation of this problem here: android - Immersive mode instructions reappear every time the device enters this mode - Stack Overflow
To disable this message you have to build a custom release of Android firmware that seems will not be a reasonable solution for your problem.
Also you can find some more details on Immersive/Fullscreen modes here: Enable fullscreen mode | Android Developers
Hope it will help you.
Software Engineer, Kutir Mobility
Posted on behalf of Zebra Technologies
Thanks for the links Dmitry - I was struggling to find any reference to it before via a Google search
there is solution specific for MC18 using some custom xml files to configure top statusbar and bottom navbars then you can create fullscreen app without this annoying message or the ability for the user to swipe down.
However there is another potential/untested way to create a fullscreen using MX config files.
Make sure to test this so it doesn't create any undesired results.
<characteristic version="7.0" type="AppMgr">
<parm name="Action" value="DisableApplication" />
<parm name="Package" value="com.android.systemui" />
And with the following:
Navigation Bar Enable/Disable
This is the On/Off switch for the on-screen Navigation Bar, which contains the BACK, HOME and RECENT soft keys. Disabling the Navigation Bar prevents the user from quitting the currently running app by means of those keys. This parameter applies only to the soft keys; it does not control capacitive or hardware keys, which can be disabled separately using the Keymapping Manager.
Parm Name: NavigationBarUsage
Option Name Description Note Requires 0 Do not change This value (or the absence of this parm from the XML) will cause no setting change; any previously selected setting will be retained.
1 Enable Enables the navigation soft keys (BACK, HOME and RECENT) on the screen-bound Navigation Bar to be displayed and usable.
2 Disable Disables the navigation soft keys (BACK, HOME and RECENT) on the screen-bound Navigation Bar.