Material-components-android: [BottomNavigationView] Adding extra padding

[h4h13]

Description: Whenever full-screen mode enabled by code icons are shrinking and after debugging I got to know that it's adding extra padding at the bottom.

Expected behavior:

Source code:

val flags = (View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_FULLSCREEN
                or View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY)

        if (PreferenceUtil.getInstance().fullScreenMode) {
            window.decorView.systemUiVisibility = flags
        }

Android API version: Android 28

Material Library version: 1.1.0-alpha09

Device: Xioami Pocco f1

To help us triage faster, please check to make sure you are using the latest version of the library.

We also happily accept pull requests.

[wcshi]

I am unable to reproduce the bug in the catalog app using the flags you provided, could you please share a sample app?

[wcshi]

@h4h13 are you setting a fixed height on the BottomNavigationView?

[GuanacoDevs]

@wcshi why you ask about the fixed height?
I have somehow a similar issue #431 where I'm using 56dp as a bnb with different values for every swXXXdp I can come up with.
Since you asked about the height I'm curious if that is something that is affecting me too.

[wcshi]

BottomNavigationView should have layout_height set to wrap_content in order to handle the extra padding adjustment from edge to edge w/o its contents getting squished.

[h4h13]

@wcshi Yes I have fixed height too for 56dp should remove fixed height works?

[h4h13]

@h4h13 I have removed fixed height but when I enable full screen this happens

By layout inspector I got it 132

[wcshi]

@h4h13 that is what I expect, the BottomNavigationView is offset by the height of the navigation bar (132). What is your desired behavior?

[h4h13]

@wcshi Should be no padding at bottom

[wcshi]

@h4h13 what system ui flags are you setting?

[h4h13]

val flags = (View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_FULLSCREEN
                or View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY)

        if (PreferenceUtil.getInstance().fullScreenMode) {
            window.decorView.systemUiVisibility = flags
        }

[paolovalerdi]

@h4h13 subclass BottomNavigationView and within the init block add the following line setOnApplyWindowInsetsListener(null) (You may need to setPadding(0) too)

[wcshi]

@paolovalerdi @h4h13 please do not subclass bottomNavigationView just to do that. Have you read this comment? It may apply to your situation as well.

[wcshi]

I used the same flags in the catalog app and did not observe the extra paddings. Could you please share a sample app to reproduces your bug?

[wcshi]

@paolovalerdi as I mentioned in this comment please file a separate bug with a sample app for your bug, thank you.

[h4h13]

@paolovalerdi It did help my problem of doing this!.

@wcshi I have subclass for theme thing bnb

[wcshi]

@h4h13 why did you subclass BottomNavigationView? To workaround the extra padding or something else?

[wcshi]

If you just want to setOnApplyWindowInsetsListener(null), you can do set it in your app instead.
https://speakerdeck.com/chrisbanes/becoming-a-master-window-fitter-droidcon-london-2017?slide=158

[wcshi]

Closing due to inactivity. Please reopen with additional info.

[IvanBean]

Here's a sample app.

Entering immersive mode with following flags:

window.decorView.systemUiVisibility = (
                View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
                        or View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                        or View.SYSTEM_UI_FLAG_FULLSCREEN
                )

Running on 1.1.0-alpha09 and above with API 28 simulator has extra padding:

I expect no padding as running on 1.1.0-alpha08 so we can use BottomNavigationView with immersive mode:

[IvanBean]

@wcshi please take a look if you have time, thanks!

[TadejZupancic]

Can we get paddingBottomSystemWindowInsets as with BottomAppBar? I would like to remove the padding and use margin instead, because I would like the text to be visible under the transparent navigation bar. The padding used makes that area opaque.

[hunterstich]

@TadejZupancic Yep. We're working on adding the same support for paddingBottomSystemWindowInsets to BottomNavigationView.