private BottomNavigationView bottomNavigationView;


    Fragment fragmentCustomer = new customerFragment();
    Fragment fragmentdestails = new DetailsFragment();
    Fragment fragmentOther = new otherFragment();

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_menu);
        //Set default
        FragmentManager fragmentManager = getSupportFragmentManager();
        FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
        fragmentTransaction.replace(R.id.main,fragmentCustomer).commit();


        bottomNavigationView = (BottomNavigationView) findViewById(R.id.navigation);
        bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                FragmentManager fragmentManager = getSupportFragmentManager();
                FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
                if(item.getItemId() == R.id.navigation_customer ) {
                    setFragment(fragmentCustomer);
                    return true;
                }
                else if(item.getItemId() == R.id.navigation_details ){
                    setFragment(fragmentdestails);
                    return true;
                }
                else{
                    setFragment(fragmentOther);
                    return true;
                }
            }
        });
    }

    private void setFragment(Fragment fragment) {

        FragmentManager fragmentManager = getSupportFragmentManager();
        String backStateName = fragment.getClass().getName();
        String fragmentTag=backStateName;
        boolean fragmentPoped = fragmentManager.popBackStackImmediate(backStateName,0);

        //Log.e("StateName",backStateName);
        Log.e("fragmentPoped",fragmentPoped+"");

        FragmentTransaction fragmentTransaction = fragmentManager.beginTransaction();
        if(!fragmentPoped){ //create fragment
            Log.e("Create fragment name",backStateName);
            fragmentTransaction.replace(R.id.main,fragment,fragmentTag);
            fragmentTransaction.setTransition(FragmentTransaction.TRANSIT_FRAGMENT_FADE);
            fragmentTransaction.addToBackStack(backStateName);
            fragmentTransaction.commit();
        }else
            Log.e("findFragmentByTag",fragmentManager.findFragmentByTag(fragmentTag)+"");

    }

    public void onBackPressed() {
        if(getFragmentManager().getBackStackEntryCount() == 0) {
            finish();
        }
        else{
            Log.e("Count Stack",getFragmentManager().getBackStackEntryCount()+"");
            super.onBackPressed();
        }

    }
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