システムバーの非表示

hideSystemBar()

private void hideSystemBar() {
        if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.R) {
            WindowInsetsController windowInsetsController = getWindow().getDecorView().getWindowInsetsController();
            windowInsetsController.hide(WindowInsets.Type.statusBars() | WindowInsets.Type.navigationBars());
            windowInsetsController.setSystemBarsBehavior(WindowInsetsController.BEHAVIOR_SHOW_TRANSIENT_BARS_BY_SWIPE);
        } else {
            View decorView = getWindow().getDecorView();
            decorView.setSystemUiVisibility(View.SYSTEM_UI_FLAG_IMMERSIVE_STICKY
                    | View.SYSTEM_UI_FLAG_FULLSCREEN
                    | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                    | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                    | View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN);
        }
    }