Android set full screen from fragment

Question

This is my question: I have an android app which allows users to go full screen for a better readability. The full screen fab toggle button is placed inside a fragment which actually contains the readings.

To make it dead simple:

• Main Activity contains Readings Fragment
• Readings Fragment contains a fab button to toggle full screen

To trigger the full screen I use this snippet:

this.fullScreenFab.setOnClickListener(v -> {
    WindowManager.LayoutParams attrs = getActivity().getWindow().getAttributes();
    if (this.isFullScreen) {
        this.isFullScreen = false;
        ((AppCompatActivity) 
getActivity()).getSupportActionBar().show();
    getActivity().getWindow().getDecorView().setSystemUiVisibility(
            View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);

} else {
    this.isFullScreen = true;
    ((AppCompatActivity) getActivity()).getSupportActionBar().hide();
    getActivity().getWindow().getDecorView().setSystemUiVisibility(
            View.SYSTEM_UI_FLAG_LOW_PROFILE
                    | View.SYSTEM_UI_FLAG_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    | View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
                    | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);

}
getActivity().getWindow().setAttributes(attrs);
});

Now, it works well, except that the status bar and action bar spaces keep showing. The activity goes FS (even Android warn me of this) but the space occupied by those two elements remain.

Full screen disabled:

Full screen enabled:

As you can see, the FS one has the top and bottom occupied, so the fragment does not go for a real full screen.

Fragment has the

android:fitsSystemWindows="true"

Send help please! Thanks in advance. Valerio

Answer 1

You should try using this flag as it is designed to remove status bar and navigation.

getActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);

NOTE: You need to manually clear this while switching or closing fragment. Else this fullscreen will be applicable till the parent activity exists. To do so,

getActivity().getWindow().clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);

Also, you can use FLAG_FULLSCREEN. Using it will effectively set a transparent notification bar but the icons on the status bar will still show up.

Answer 2

Kotlin

In onViewCreated() to make fragment fullscreen

requireActivity().window.addFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS)

In onDetach() to clear fullscreen flag so it will not affect to other fragment which is open in Activity

requireActivity().window.clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS)

--x--x--x--x--x--x--x--x--x--

Java

In onViewCreated() to make fragment fullscreen

requireActivity().getWindow().addFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);

In onDetach() to clear fullscreen flag so it will not affect to other fragment which is open in Activity

requireActivity().getWindow().clearFlags(WindowManager.LayoutParams.FLAG_LAYOUT_NO_LIMITS);

Answer 3

System UI fullscreen flags are now deprecated, for API level 30 and above override onWindowFocusChanged() in your MainActivity

override fun onWindowFocusChanged(hasFocus: Boolean) {
    super.onWindowFocusChanged(hasFocus)
    if (hasFocus) hideSystemUI() else showSystemUI()
}

private fun hideSystemUI() {
    if (Build.VERSION.SDK_INT >= 30) {
        window.insetsController?.apply {
            hide(WindowInsets.Type.statusBars() or WindowInsets.Type.navigationBars())
        }
    } else {
        // Enables regular immersive mode.
        // For "lean back" mode, remove SYSTEM_UI_FLAG_IMMERSIVE.
        // Or for "sticky immersive," replace it with SYSTEM_UI_FLAG_IMMERSIVE_STICKY
        window.decorView.systemUiVisibility = (View.SYSTEM_UI_FLAG_IMMERSIVE
                // 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_STABLE
                or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                // Hide the nav bar and status bar
                or View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_FULLSCREEN)
    }
}
private fun showSystemUI() {
    if (Build.VERSION.SDK_INT >= 30) {
        window.insetsController?.apply {
            show(WindowInsets.Type.statusBars() or WindowInsets.Type.navigationBars())
        }
    } else {
        window.decorView.systemUiVisibility = (View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                or View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                or View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN)
    }
}