Bottom Navigation View in Android

import android.os.Bundle;
import android.support.annotation.NonNull;
import android.support.design.widget.BottomNavigationView;
import android.support.design.widget.Snackbar;
import android.support.v7.app.AppCompatActivity;
import android.view.MenuItem;
import android.widget.TextView;
import android.widget.Toast;

public class MainActivity extends AppCompatActivity {
       private BottomNavigationView.OnNavigationItemSelectedListener ms
            = new BottomNavigationView.OnNavigationItemSelectedListener() {

        @Override
        public boolean onNavigationItemSelected(@NonNull MenuItem item) {
            switch (item.getItemId()) {
                case R.id.navigation_home:
                    Toast.makeText(MainActivity.this, "First", Toast.LENGTH_SHORT).show();
                    return true;
                case R.id.navigation_dashboard:
                    Toast.makeText(MainActivity.this, "Second", Toast.LENGTH_SHORT).show();
                    return true;
                case R.id.navigation_notifications:
                    Toast.makeText(MainActivity.this, "Third", Toast.LENGTH_SHORT).show();
                    return true;
            }
            return false;
        }
    };

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(R.layout.activity_main);
        BottomNavigationView navigation = (BottomNavigationView) findViewById(R.id.navigation);
        navigation.setOnNavigationItemSelectedListener(ms);
    }
}
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    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/container"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    android:orientation="vertical"
tools:context="com.example.mybottomnavigation.MainActivity">
            android:id="@+id/content"
        android:layout_width="match_parent"
        android:layout_height="0dp"
        android:layout_weight="1">
                    android:layout_width="match_parent"
            android:layout_height="wrap_content"
            android:textSize="20sp"
            android:padding="20dp"
            android:text="Deep Singh"
            android:gravity="center"/>
   
         android:id="@+id/navigation"
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:layout_gravity="bottom"
        app:itemTextColor="#ffffff"
        app:itemIconTint="#ffffff"
        app:itemBackground="@color/orange"
        app:menu="@menu/navigation" />

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< menu  xmlns:android="http://schemas.android.com/apk/res/android" >
    < item android:id="@+id/navigation_home"
        android:icon="@drawable/gallery"
        android:title="@string/title_home" />
    < item android:id="@+id/navigation_dashboard"
        android:icon="@drawable/gg"
        android:title="@string/title_dashboard" />
    < item android:id="@+id/navigation_notifications"
        android:icon="@drawable/gg"
        android:title="@string/title_notifications" />
< /menu>
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