There is no way override the default gesture flags.
If what you want is to resize your fragment when the system bars become visible, you should register a View.OnSystemUiVisibilityChangeListener
to mDecorView
. This listener will be notified of system UI changes. Once you get a notification that the bars come visible (whatever the reason) you can do the necessary changes to resize your fragment. See https://developer.android.com/training/system-ui/visibility.html for an example on how the listener can be used.