Immersive mode instructions reappear every time the device enters this mode

Question

My app uses the new \"immersive mode\" by calling (in onCreate):

getWindow().getDecorView().setSystemUiVisibility(View.SYSTEM_UI_FLAG_HIDE_NAVIGAT

Answer 1

More succinctly - in K, users will see the confirmation when entering immersive mode if:

• They have not yet confirmed it for that app (package).
• They "panicked" last time they were in immersive mode. "Panic" in this case means toggling the screen off, then back on in under 5 seconds (by default).

Answer 2

Really interesting question! Thanks to your clear instructions, reproducing the issue wasn't a problem.

Alright, after digging through the source for almost 30-minutes and saying why would they do this? a bunch of times, I think I finally get it. I'll try to explain the best I can, but this is only my interpretation, and may not be correct:

Someone at android realized that the Immersive Mode will send people into a state of panic: how do i exit? (_sorry, I don't know what else the panic would be about_).

In this state of panic, the user will turn to the POWER BUTTON

.... > Power button --> User turns screen off (at x milliseconds since EPOCH)

.... > Praying that the navigation bar comes back

.... > Power button --> User turns screen on (at y milliseconds since EPOCH)

Now, the duration y - x is of significance. We'll discuss it a bit later, but first, let's look at how panic is defined:

panic happens when Praying the navigation bar comes back lasts less than 5 seconds. This value is held by:

mPanicThresholdMs = context.getResources()
                 .getInteger(R.integer.config_immersive_mode_confirmation_panic);

<!-- Threshold (in ms) under which a screen off / screen on will be considered 
     a reset of the immersive mode confirmation prompt.-->
<integer name="config_immersive_mode_confirmation_panic">5000</integer>

Ah, okay. So, it doesn't matter if the user has already acknowledged once, the prompt will be back if the above-mentioned criterion is met - even on the 100th launch.

And here's where the action happens:

public void onPowerKeyDown(boolean isScreenOn, long time, boolean inImmersiveMode) {
    if (mPanicPackage != null && !isScreenOn && (time - mPanicTime < mPanicThresholdMs)) {
        // turning the screen back on within the panic threshold
        unconfirmPackage(mPanicPackage);
    }
    if (isScreenOn && inImmersiveMode) {
        // turning the screen off, remember if we were in immersive mode
        mPanicTime = time;
        mPanicPackage = mLastPackage;
    } else {
        mPanicTime = 0;
        mPanicPackage = null;
    }
}

(time - mPanicTime < mPanicThresholdMs) ==> ( y - x ) < 5000

unconfirmPackage(mPanicPackage) removes mPanicPackage (yours) from the list of packages stored under Settings.Secure.IMMERSIVE_MODE_CONFIRMATIONS.

Needless to say, I find this strange... and wrong. Even if the user is in panic, and takes the power button route, s/he won't see the helpful reminder until next launch. So, what's the point?

Or may be, I am wrong about the definition of panic.

so there's nothing I can do to change this situation, correct?

Correct. To fix this, you would have to add your package-name to value held by Settings.Secure.IMMERSIVE_MODE_CONFIRMATIONS. But, to write to a secure setting, your app requires WRITE_SECURE_SETTINGS permission - not for use by third-party applications.

Links:

ImmersiveModeConfirmation (helper class that manages showing/hiding of confirmation prompt)