Bottom Navigation in Android Development

Introduction

Bottom Navigation is a UI component in Android that allows users to quickly navigate between top-level views in an application. It is typically used when the app has three to five top-level destinations.

Setting Up Bottom Navigation

To start using Bottom Navigation, you need to add the necessary dependencies to your project. Open your build.gradle file and add the following dependency:

dependencies {
    implementation 'com.google.android.material:material:1.3.0'
}

Creating the Bottom Navigation Menu

Create a menu resource file in the res/menu directory. Name the file bottom_nav_menu.xml and add the following content:

<menu xmlns:android="http://schemas.android.com/apk/res/android">
    <item
        android:id="@+id/nav_home"
        android:icon="@drawable/ic_home"
        android:title="Home" />
    <item
        android:id="@+id/nav_search"
        android:icon="@drawable/ic_search"
        android:title="Search" />
    <item
        android:id="@+id/nav_notifications"
        android:icon="@drawable/ic_notifications"
        android:title="Notifications" />
    <item
        android:id="@+id/nav_profile"
        android:icon="@drawable/ic_profile"
        android:title="Profile" />
</menu>

Adding Bottom Navigation to Your Layout

Next, add the Bottom Navigation component to your activity's layout file (e.g., activity_main.xml):

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

    <fragment
        android:id="@+id/nav_host_fragment"
        android:name="androidx.navigation.fragment.NavHostFragment"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_above="@id/bottom_navigation_view"
        app:defaultNavHost="true"
        app:navGraph="@navigation/nav_graph" />

    <com.google.android.material.bottomnavigation.BottomNavigationView
        android:id="@+id/bottom_navigation_view"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_alignParentBottom="true"
        android:background="?android:attr/windowBackground"
        app:menu="@menu/bottom_nav_menu" />

</RelativeLayout>

Handling Navigation Item Selections

In your activity (e.g., MainActivity.java), set up an OnNavigationItemSelectedListener for the Bottom Navigation view:

import android.os.Bundle;
import androidx.annotation.NonNull;
import androidx.appcompat.app.AppCompatActivity;
import com.google.android.material.bottomnavigation.BottomNavigationView;

public class MainActivity extends AppCompatActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);

        BottomNavigationView bottomNavigationView = findViewById(R.id.bottom_navigation_view);
        bottomNavigationView.setOnNavigationItemSelectedListener(new BottomNavigationView.OnNavigationItemSelectedListener() {
            @Override
            public boolean onNavigationItemSelected(@NonNull MenuItem item) {
                switch (item.getItemId()) {
                    case R.id.nav_home:
                        // Handle home navigation
                        return true;
                    case R.id.nav_search:
                        // Handle search navigation
                        return true;
                    case R.id.nav_notifications:
                        // Handle notifications navigation
                        return true;
                    case R.id.nav_profile:
                        // Handle profile navigation
                        return true;
                }
                return false;
            }
        });
    }
}

Conclusion

Bottom Navigation is a powerful tool for organizing top-level views in your Android app. By following this tutorial, you should now have a functional Bottom Navigation component integrated into your application. For further customization, refer to the official Android documentation.