I have a simple BottomNavigationView with two menu items (Home Fragment, Settings Fragment) in an activity.

I have implemented onNavigationItemSelectedListener and onNavigationItemSelected.

Also bottomNavigationView.setOnNavigationItemSelectedListener(this);

App page lands on the Home Fragment.

onNavigationItemSelected is being called when I switch between menu items but When I first launch the app and tap on the same menu Item i.e. Home Fragment, onNavigationItemSelected is not being called.

I would need to show a toast whenever the user clicks on the home page when user is already in home page but onNavigationItemSelected event is not triggered.

CodePudding user response：

in mainActivity XML in FragmentContainerView add
android:name="Fragment.HomeFragment"

            <androidx.fragment.app.FragmentContainerView
                android:id="@ id/fragment_container"
                android:name="Fragment.HomeFragment"
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:layout_above="@id/bottom_navigation" />

then goto main activity onCreatemethod

  bottom_navigation.setOnNavigationItemSelectedListener {
   
        when (it.itemId) {
    
            R.id.menuHome_id -> {
               val bpfragment = HomeFragment()
                supportFragmentManager.beginTransaction().replace(R.id.fragment_container, bpfragment).commit()
            }
            R.id.menuSetting_id -> {
                val bpfragment = SettingsFragment()
                supportFragmentManager.beginTransaction().replace(R.id.fragment_container, bpfragment).commit()
            }

        }
        true
    }

still problem give your code of container, bottom navigation and transaction code. it will be easier to solve if you provide code too.

CodePudding user response：

First of all we do this in the MainActivity

@Override
    public boolean onNavigationItemSelected(@NonNull MenuItem item) {
        int v = item.getItemId();
        if(v==R.id.home)
        {
            getSupportActionBar().setTitle("Home");
            Fragment fragment = new HomeFragment();
            FragmentManager fm = getSupportFragmentManager();
            fm.beginTransaction().replace(R.id.frame_layout, fragment).commit();
        }
        else if (v==R.id.dash_board)
        {
            getSupportActionBar().setTitle("Dashboard");
            Fragment fragment = new DashboardFragment();
            FragmentManager fm = getSupportFragmentManager();
            fm.beginTransaction().replace(R.id.frame_layout, fragment).commit();
        }
   return true;
    }
};

This is a example here If you want to know in detail then click here