The issue I’m having is that I’m unable to get the bottom navigation to switch between fragments.

This is de activity_main.xml:

<?xml version="1.0" encoding="utf-8"?>
<androidx.constraintlayout.widget.ConstraintLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    tools:context=".MainActivity">

    <androidx.fragment.app.FragmentContainerView
        android:id="@+id/nav_host_fragment"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        app:defaultNavHost="true"
        app:layout_constraintBottom_toTopOf="@+id/bottomNavigationView"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent"
        app:layout_constraintTop_toTopOf="parent"
        app:navGraph="@navigation/nav" />


    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/bottomNavigationView"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        app:menu="@menu/menu_bottom"
        app:layout_constraintBottom_toBottomOf="parent"
        app:layout_constraintEnd_toEndOf="parent"
        app:layout_constraintStart_toStartOf="parent" />

</androidx.constraintlayout.widget.ConstraintLayout>

This is the MainActivity.kt:

package com.example.flag

import android.os.Bundle
import androidx.appcompat.app.AppCompatActivity
import androidx.navigation.fragment.NavHostFragment
import androidx.navigation.ui.NavigationUI
import androidx.navigation.ui.setupWithNavController
import com.example.flag.databinding.ActivityMainBinding

class MainActivity : AppCompatActivity() {

    private lateinit var binding: ActivityMainBinding

    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        binding = ActivityMainBinding.inflate(layoutInflater)
        setContentView(binding.root)

        setupNavigation()
    }

    private fun setupNavigation() {
        val bottomNavigationView = binding.bottomNavigationView
        val navHostFragment = supportFragmentManager.findFragmentById(R.id.nav_host_fragment) as NavHostFragment
        val navController = navHostFragment.navController

        bottomNavigationView.setupWithNavController(navController)
    }

}

This is the nav.xml:

<?xml version="1.0" encoding="utf-8"?>
<navigation xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:tools="http://schemas.android.com/tools"
    android:id="@+id/nav"
    app:startDestination="@id/page_profile">

    <fragment
        android:id="@+id/page_profile"
        android:name="com.example.flag.ProfileFragment"
        android:label="fragment_profile"
        tools:layout="@layout/fragment_profile" />

    <fragment
        android:id="@+id/page_search"
        android:name="com.example.flag.SearchFragment"
        android:label="fragment_search"
        tools:layout="@layout/fragment_search" />

    <fragment
        android:id="@+id/page_chats"
        android:name="com.example.flag.ChatsFragment"
        android:label="fragment_chats"
        tools:layout="@layout/fragment_chats" />
</navigation>

This is the menu_bottom.xml:

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android">
<item
    android:id="@+id/page_profile"
    android:icon="@drawable/person_icon"
    android:title="Profile" />
<item
    android:id="@+id/page_search"
    android:icon="@drawable/icon_search"
    android:title="Search" />
<item
    android:id="@+id/page_chats"
    android:icon="@drawable/chat_icon"
    android:title="Chats" />
</menu>

I tried using ChatGPT and using already existing projects that work, and even after trying everything, I can’t get my navigation to work.