React Native Wix Navigation V2 - Android Navigation Buttons Bar Hide - HTC - Nexus - FullScreen

MainActivity.java

package com.example.app;

import com.reactnativenavigation.NavigationActivity;
import android.content.Intent;
import android.content.res.Configuration; 
import android.os.Bundle;
import android.view.View;

public class MainActivity extends NavigationActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);

        final int flags = View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                | View.SYSTEM_UI_FLAG_LOW_PROFILE
                | View.SYSTEM_UI_FLAG_FULLSCREEN
                | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                | View.SYSTEM_UI_FLAG_IMMERSIVE;

            getWindow().getDecorView().setSystemUiVisibility(flags);

            final View decorView = getWindow().getDecorView();
            decorView
                .setOnSystemUiVisibilityChangeListener(new View.OnSystemUiVisibilityChangeListener()
                {

                    @Override
                    public void onSystemUiVisibilityChange(int visibility)
                    {
                        if((visibility & View.SYSTEM_UI_FLAG_FULLSCREEN) == 0)
                        {
                            decorView.setSystemUiVisibility(flags);
                        }
                    }
                });
    }

    @Override
    public void onWindowFocusChanged(boolean hasFocus)
    {
        super.onWindowFocusChanged(hasFocus);
            getWindow().getDecorView().setSystemUiVisibility(
                View.SYSTEM_UI_FLAG_LAYOUT_FULLSCREEN
                | View.SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION
                | View.SYSTEM_UI_FLAG_LAYOUT_STABLE
                | View.SYSTEM_UI_FLAG_LOW_PROFILE
                | View.SYSTEM_UI_FLAG_FULLSCREEN
                | View.SYSTEM_UI_FLAG_HIDE_NAVIGATION
                | View.SYSTEM_UI_FLAG_IMMERSIVE);
    }

}

Hi,
Thanks for great help,
I'm wondering how I can do this in just one screen, for example if I want the modal to be fullscreen.
Best regards