Create Amazing Bottom Navigation Bar In Android

Google has added the Bottom Navigation menu to Google Support Library. Bottom navigation bars make it easy to switch between the view within a single layout. As per material design guidelines, now we can add it using a standard library. In this article, I will explain how to add the bottom navigation bar to the android app.

As per material design guideline, bottom navigation bar should be used where we need to use 3 to 5 menu item.  More than that menu item is not recommended for the bottom navigation bar. If you would like to know more about bottom navigation bar recommendation you can check on material design website here.

1. Introduction

In this tutorial, we are going to create an app to show how to use and implement the Bottom Navigation Bar in Android. We will create two fragments with different kind of content and view which will be changed as you touch the tab from Bottom Navigation Bar.

2. Create the project for Bottom Navigation Bar with Activity

So creating the project Go To File> New > New Project, Put the name of your project here, for example, we have take name as Bottom Navigation Bar Demo then click on Next and select the empty activity.

3. Setting the dependency Bottom Navigation Bar for Activity

As I explained at the starting of this tutorial Bottom Navigation Bar added to support Library from version 25.0.0.  So add the dependency in project build.gradle files and sync the project. So we can add the Bottom Navigation bar to our Activity, but for that, we need to add the follwing dependency to our project first.

   compile 'com.android.support:appcompat-v7:25.2.0'  
   compile 'com.android.support:design:25.2.0'  

4. Adding Bottom Navigation Bar for Activity to your XML

Before adding the Bottom Navigation Bar to our app first we will test our application to check whether the application is working or not. So just click on run button from Android Studio Navigation menu and select the emulator.
Now open your main activity XML files and add the Bottom Navigation Bar to your activity_main.xml file.

<android.support.design.widget.BottomNavigationView
    android:id="@+id/bottom_navigation"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom"
    android:background="?android:attr/windowBackground"
    app:menu="@menu/bottom_nav_menu"
     />

An important point to note here is that we have added it under Linear Layout and apart for that, I have added a Frame Layout also inside Linear layout so that we can use this later on to show our fragment. You can check the layout using the Android Layout editor by clicking on Design Button it will look like as given in the screenshots.

 

 

 

5. Create Bottom Navigation Bar Menu Item

As you can see in the screenshots we have just added the Bottom Navigation Bar to our project, but there is no any item inside our Bottom Navigation Bar. So it is time to add the menu Item to it.

 So for adding the menu item we need to add a menu resource files inside menu folder. Right click on menu folder and create an XML file with the name of bottom_nav_menu_item.xml, you can choose your name as per your convenience and if menu folder does not exist then first create the menu folder and then added the menu XML files.

 5.1 Create Menu Folder

So For creating the menu folder just right-click on res folder and select the New>  New Resource Directory and select the type from the Resource type drop down option, Put the name of the directory as menu and click on Ok Button.

5.1 Create Menu resource File

Now, similarly right-click on menu directory and select the Menu Resource Files put the name of your menu XML files as bottom_nav_menu_item.xml.

Your menu resource files will get created, now add the menu item to our resource files.
For adding the menu Item to add the below code to your XML files or you can use the Android Studio Design Tool to add the menu item to your menu resource files.

<menu xmlns:app="http://schemas.android.com/apk/res-auto"
    xmlns:android="http://schemas.android.com/apk/res/android">

    <item
    android:id="@+id/Home"
    android:icon="@drawable/ic_home_black_24dp"
    android:title="Home" />
    <item
        android:id="@+id/Gallery"
        android:icon="@android:drawable/ic_menu_gallery"
        android:title="Gallery" />
</menu>

6. Setting menu item to Bottom Navigation Bar

We have created the menu item in our last steps which contain two item Home and Gallery, but if we run our app this menu will now show in our app because we still not added the menu item to our Bottom Navigation Bar. Now we will add the menu item to the navigation menu.

For adding the menu item open the main_activity.xml files once again and add the below line to your Bottom Navigation Bar declaration section.

 app:menu="@menu/bottom_nav_menu"

So, After this change, our full Bottom Navigation Bar declaration looks like as given below.

<android.support.design.widget.BottomNavigationView
    android:id="@+id/bottom_navigation"
    android:layout_width="match_parent"
    android:layout_height="wrap_content"
    android:layout_gravity="bottom"
    android:background="?android:attr/windowBackground"
    app:menu="@menu/bottom_nav_menu"
     />

At this point, you may want to test your app whether your menu item is showing or not, so hit the run button in from your Android Studio Menu bar and check out the application layout, if everything works well and implemented correctly then you will see two menu item inside your Bottom navBar menu one is Home and Gallery are visible.

7. Detecting touch or click event to switch the View

As of now, we have not done anything related to coding part of Bottom Navigation Bar implementation. So now its time to do some coding to see the real implementation of Bottom Navigation Bar. We need to modify our MainActivity.java file similar as given below to see the Bottom Navigation Bar in action.

public class MainActivity extends AppCompatActivity {
    ActionBar actionBar;
    private BottomNavigationView.OnNavigationItemSelectedListener mOnNavigationItemSelectedListener
            = new BottomNavigationView.OnNavigationItemSelectedListener() {
        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            switch (item.getItemId()) {
                case R.id.Home:
                    actionBar.setTitle("Home");
                    return true;
                case R.id.Gallery:
                    actionBar.setTitle("Gallery");
                    return true;
            }
            return false;
        }

    };
    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        actionBar=getSupportActionBar();
        BottomNavigationView bottom_navigation = (BottomNavigationView) findViewById(R.id.bottom_navigation);
        bottom_navigation.setOnNavigationItemSelectedListener(mOnNavigationItemSelectedListener);
    }
}

Test your app again and check by tapping on both bottom menu item. You will see that top title bar heading is getting changed as you change the view. So we have completed the implementation part. Next, we will integrate the fragment with these menu items so that View can also be changed as you tab on the bottom navigation bar menu item.

8. Loading Fragment in Bottom Navigation Bar

Loading the Fragment on Item click is very important because this is the real use of the menu. Because you want to show different layout to your user when they tab on home and Gallery menu Item.

So for adding the fragment we need to create two fragments and attach that fragment with item selected listener. Below is the fragment that we are creating to use with home and gallery item of our Bottom Navigation Bar.

HomeFragment.java

public class HomeFragment extends Fragment {
    public HomeFragment() {
        // Required empty public constructor
    }
    public static HomeFragment newInstance() {
        HomeFragment fragment = new HomeFragment();
        return fragment;
    }
    @Override
    public void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }
    @Override
    public void onActivityCreated(Bundle savedInstanceState) {
        super.onActivityCreated(savedInstanceState);
    }
    @Override
    public View onCreateView(LayoutInflater inflater, ViewGroup container,
                             Bundle savedInstanceState) {
        // Inflate the layout for this fragment

        return inflater.inflate(R.layout.fragment_home, container, false);
    }
}

fragment_home.xml

<FrameLayout 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="com.debugandroid.bottomnavigationdemo.MainActivity">

    <TextView
        android:layout_width="wrap_content"
        android:layout_height="wrap_content"
        android:id="@+id/text"
        android:text="Home Fragment">

    </TextView>
</FrameLayout>

In a similar way as we created our Home Fragment we can create our Gallery Fragment. It's time to bind the fragment with click event of the menu item.  For this, we are adding two methods to our MainActivity.java files.

    public void setHomeFragment(){
        FragmentManager fm= getSupportFragmentManager();
        FragmentTransaction ft=fm.beginTransaction();
        Fragment homeFragment=HomeFragment.newInstance();
        ft.replace(R.id.main_container,homeFragment);
        ft.commit();
    }

    public void setGalleryFragment(){
        FragmentManager fm= getSupportFragmentManager();
        FragmentTransaction ft=fm.beginTransaction();
        Fragment galleryFragment=GalleryFragment.newInstance();
        ft.replace(R.id.main_container,galleryFragment);
        ft.commit();
    }

Now, we need to call these two methods from the respective case option of our Bottom Navigation Bar listener. Which will change the layout when user tab on the respective menu item of Navigation Bar.

public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            switch (item.getItemId()) {
                case R.id.Home:
                    actionBar.setTitle("Home");
                    setHomeFragment();
                    return true;
                case R.id.Gallery:
                    actionBar.setTitle("Gallery");
                    setGalleryFragment();
                    return true;
            }
            return false;
        }

We are all done now test your application and you see that your view is getting changed as you click on Bottom Navigation Menu.

9. Conclusion

We have created a fully functioning application with Bottom Navigation Bar. It is quite easy to implement and gives good UX to our app user.

In short, this is up to us how we are using this in our application. But I recommend following the Bottom Navigation Bar material design guidelines to use this in your mobile application. As per that it is good to use this if we have three to five menu item to show at the bottom.

You can check out the other option and function on Android Developer Official Sites.