How to remove top status bar black background

Question

I'd like to create a TRUE fullscreen activity, but there is always a black status bar on screen top. Android 9.0.

I've tried almost all I can find with Google and existing Apps with similar jobs. Manifest, code, style, AS sample fullscreen activity, all were tried.

styles.xml:

    <style name="AppThemeA" parent="@style/Theme.AppCompat.Light.NoActionBar">
        <item name="android:statusBarColor">@android:color/transparent</item>
        <item name="android:windowNoTitle">true</item>
        <item name="android:windowActionBar">false</item>
        <item name="android:windowFullscreen">true</item>
        <item name="android:windowContentOverlay">@null</item>
        <item name="android:windowTranslucentStatus">true</item>
        <item name="android:windowTranslucentNavigation">true</item>
    </style>

Manifest:

<activity android:name=".ScreenActivity" android:theme="@style/AppThemeA" />

Layout:

<?xml version="1.0" encoding="utf-8"?>
<androidx.coordinatorlayout.widget.CoordinatorLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="match_parent">

    <FrameLayout
        android:id="@+id/rootLayout"
        android:fitsSystemWindows="true"
        android:layout_width="match_parent"
        android:layout_height="match_parent" />

</androidx.coordinatorlayout.widget.CoordinatorLayout>

Kotlin (commented lines are tried and failed):

class ScreenActivity : AppCompatActivity() {
    override fun onCreate(savedInstanceState: Bundle?) {
        //setTheme(R.style.AppThemeDetector)
        super.onCreate(savedInstanceState)


        //window.setFlags(WindowManager.LayoutParams.FLAG_FULLSCREEN, WindowManager.LayoutParams.FLAG_FULLSCREEN)
        //window.setFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS, WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS)
        //window.decorView.systemUiVisibility = View.SYSTEM_UI_FLAG_LIGHT_STATUS_BAR or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION or View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY or View.SYSTEM_UI_FLAG_FULLSCREEN

        /*
        window.decorView.systemUiVisibility = (
                View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                        or View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                        or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                        or View.SYSTEM_UI_FLAG_FULLSCREEN
                )*/

        setContentView(R.layout.activity_screen_detector)
        ...
    }
}

The expected result:

What I actually got:

[[[[ Solution ]]]]

Found what caused this. You should set the App to FullScreen App in Settings -> Display.

https://www.gottabemobile.com/how-to-enable-full-screen-apps-on-galaxy-s10

So fixed. Thanks for all your help.

Answer 1

Add this method in your activity

public static void hideSystemUI() {
    getWindow().getDecorView().setSystemUiVisibility(
            View.SYSTEM_UI_FLAG_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_LOW_PROFILE
                    | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    | View.SYSTEM_UI_FLAG_IMMERSIVE
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);
}

before adding this call this below super.onCreate(savedInstanceState); onCreate

    hideSystemUI();
    if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.P) {
        getWindow().getAttributes().layoutInDisplayCutoutMode = WindowManager.LayoutParams.LAYOUT_IN_DISPLAY_CUTOUT_MODE_SHORT_EDGES;
    }

above attribute is use if your device have notch cutout for camera.

Answer 2

I had a problem with displaying content through the notch or the cutout area. Found this in the docs:

LAYOUT_IN_DISPLAY_CUTOUT_MODE_SHORT_EDGES - Content renders into the cutout area in both portrait and landscape modes.

Key thing for me was this line in the activity style:

// Important to draw through the cutouts
<item name="android:windowLayoutInDisplayCutoutMode">shortEdges</item> 

I wanted to show an image in immersive mode, and when I click it, the system UI (status & navigation bars) should show up.

Here is my complete solution:

1- Methods to show/hide system UI in the Activity

private fun hideSystemUI() {
    sysUIHidden = true
    window.decorView.systemUiVisibility = (
            View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
            or View.SYSTEM_UI_FLAG_LAYOUT_STABLE 
            // Hide the nav bar and status bar
            or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION // Hide nav bar
            or View.SYSTEM_UI_FLAG_FULLSCREEN // Hide status bar
            )
}


private fun showSystemUI() {
    sysUIHidden = false
    window.decorView.systemUiVisibility = (
            View.SYSTEM_UI_FLAG_LAYOUT_STABLE
            // Set the content to appear under the system bars so that the
            // content doesn't resize when the system bars hide and show.
            or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION // layout Behind nav bar
            or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN // layout Behind status bar
            )
}

2- Make sure this in the root view of your xml layout

android:fitsSystemWindows="false"

3- The Style for the Full screen Activity will give status/navigation bars a semi transparent background when they show up:

<style name="FullscreenTheme" parent="AppTheme">
    <item name="android:actionBarStyle">@style/FullscreenActionBarStyle</item>
    <item name="android:windowActionBarOverlay">true</item>
    <item name="android:windowBackground">@null</item>
    <item name="metaButtonBarStyle">?android:attr/buttonBarStyle</item>
    <item name="metaButtonBarButtonStyle">?android:attr/buttonBarButtonStyle</item>
    <item name="android:statusBarColor">#50000000</item>
    <item name="android:navigationBarColor">#50000000</item>
    // Important to draw behind cutouts
    <item name="android:windowLayoutInDisplayCutoutMode">shortEdges</item> 
</style>

<style name="FullscreenActionBarStyle" parent="Widget.AppCompat.ActionBar">
    <item name="android:background">@color/sysTransparent</item>
</style>