在遵循Bruno的评论后，我更新了代码并解决了错误：

getWindow().getDecorView().setSystemUiVisibility(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.
            | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
            | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
            // Hide the nav bar and status bar
            | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION);

请注意，我并不想完全删除appbar，因此我没有在最后包含以下行| View.SYSTEM_UI_FLAG_FULLSCREEN);。

更新

请注意，如果您希望布局显示在appbar下面，而不是appbar下面，则需要删除此行

| View.SYSTEM_UI_FLAG_LAYOUT_STABLE

对于我导航到的片段，这对我很有效，我把这段代码放在MainActivity中

navController = Navigation.findNavController(this, R.id.nav_host_fragment_activity_main);
        NavigationUI.setupActionBarWithNavController(this, navController, appBarConfiguration);
        NavigationUI.setupWithNavController(binding.navView, navController);

        navController.addOnDestinationChangedListener(new NavController.OnDestinationChangedListener() {
            @Override
            public void onDestinationChanged(@NonNull NavController navController,
                                             @NonNull NavDestination navDestination,
                                             @Nullable Bundle bundle) {
                BottomNavigationView navBar = findViewById(R.id.nav_view);
                if(navDestination.getId() == R.id.navigation_librarySlideShowFragment ||
                        navDestination.getId() == R.id.navigation_settings ||
                        navDestination.getId() == R.id.wifiSettingsFragment ||
                        navDestination.getId() == R.id.playbackFragment) {
                    navBar.setVisibility(View.GONE);
                } else {
                    navBar.setVisibility(View.VISIBLE);
                }
            }