Android_Nav_Menu.java

public class your_activity extends AppCompatActivity implements NavigationView.OnNavigationItemSelectedListener {
	
    private DrawerLayout myDrawerLayout;
    private ActionBarDrawerToggle myToggle;
    NavigationView navigationView;
    DrawerLayout mydrawer;
	
	//-----> into onCreate method
	navigationView = (NavigationView) findViewById(R.id.nav_view_id);
	navigationView.setNavigationItemSelectedListener(this);
	mydrawer = (DrawerLayout) findViewById(R.id.drawer);
	
	// call method
	nav_menu_method();
	dynamically_generate_nav_menu_item();
	//<----- into onCreate method
	
	//-----> all about navigation menu
	public void nav_menu_method(){
		myDrawerLayout = (DrawerLayout)findViewById(R.id.drawer_layout_id);
		myToggle = new ActionBarDrawerToggle(your_activity.this,myDrawerLayout,R.string.open_string,R.string.close_string);
		myDrawerLayout.addDrawerListener(myToggle);
		myToggle.syncState();
		getSupportActionBar().setDisplayHomeAsUpEnabled(true);

		// Toggle button color
		myToggle.getDrawerArrowDrawable().setColor(getResources().getColor(R.color.color_name));
	}

	@Override
	public boolean onOptionsItemSelected(MenuItem item) {
		if (myToggle.onOptionsItemSelected(item)){
			return true;
		}
			return super.onOptionsItemSelected(item);
	}
	//<----- all about navigation menu

	//-----> dynamically generate navigation menu item
	public void dynamically_generate_nav_menu_item(){
		String items_array[] = {"item1","item2","item3"};

		Menu the_nav_menu = navigationView.getMenu();
		for (int i=0; i<items_array.length; i++){
			MenuItem menu_items = the_nav_menu.add(R.id.group_items, i, Menu.NONE, items_array[i]);
			menu_items.setIcon(R.drawable.item_icon);
			menu_items.getIcon().setColorFilter(ContextCompat.getColor(your_activity.this, R.color.color_name), PorterDuff.Mode.SRC_IN);
		}
	}
	//<----- dynamically generate navigation menu item
  
  @SuppressWarnings("StatementWithEmptyBody")
  @Override
  public boolean onNavigationItemSelected(MenuItem item) {
  int id = item.getItemId();

    switch (id){
      case R.id.normal_item1:
        mydrawer.closeDrawer(GravityCompat.START); // it will close nav after click item
        // do something
        break;

      case R.id.normal_item2:
        mydrawer.closeDrawer(GravityCompat.START);
        // do something
        break;

      case R.id.normal_item3:
        mydrawer.closeDrawer(GravityCompat.START);
        // do something
        break;

      case 0:
        mydrawer.closeDrawer(GravityCompat.START);
        // do something for dynamic 1st item
        break;

      case 1:
        mydrawer.closeDrawer(GravityCompat.START);
        // do something for dynamic 2nd item
        break;

      case 2:
        mydrawer.closeDrawer(GravityCompat.START);
        // do something for dynamic 3rd item
        break;

      default:
        break;
    }
    //mydrawer.closeDrawer(GravityCompat.START);
    return true;
  }
}

// your_activity, myDrawerLayout, myToggle, navigationView, nav_view_id, drawer_layout_id, open_string, close_string, color_name, items_array, the_nav_menu, menu_items, item_icon, id, mydrawer, normal_item

build.gradle

// import it into dependencies
implementation 'com.android.support:design:26.1.0'

// design version should be same to appcompat.

dimen.xml

<?xml version="1.0" encoding="utf-8"?>
<resources>
    <dimen name="nav_header_height">176dp</dimen>
</resources>

<!-- 176dp -->

nav_header_layout.xml

<?xml version="1.0" encoding="utf-8"?>
<LinearLayout
    xmlns:android="http://schemas.android.com/apk/res/android"
    android:layout_width="match_parent"
    android:layout_height="@dimen/nav_header_height"
    android:background="@drawable/nav_header_image_or_file"
    android:gravity="bottom"
    android:orientation="vertical">
</LinearLayout>

<!-- nav_header_height, nav_header_image_or_file -->

nav_menu.xml

<?xml version="1.0" encoding="utf-8"?>
<menu xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">

    <group
        android:id="@+id/normal_item"
        android:checkableBehavior="none"
        android:orderInCategory="0">
        <item
            android:id="@+id/normal_item1"
            android:icon="@drawable/item_icon1"
            android:title="Refresh"/>
        <item
            android:id="@+id/normal_item2"
            android:icon="@drawable/item_icon2"
            android:title="Notes"/>

        <item
            android:id="@+id/normal_item3"
            android:icon="@drawable/item_icon3"
            android:title="Bookmarked"/>
    </group>

    <item app:showAsAction="always">
		<menu
			android:id="@+id/group_items"
			android:checkableBehavior="none"
			android:orderInCategory="1">

			<!-- all dynamic item will come here -->

		</menu>
	</item>
</menu>

<!-- normal_item, normal_item, item_icon, group_items -->

your_activity_xml.xml

<?xml version="1.0" encoding="utf-8"?>
<android.support.v4.widget.DrawerLayout
    android:id="@+id/drawer_layout_id"
    android:layout_width="match_parent"
    android:layout_height="match_parent"
    xmlns:android="http://schemas.android.com/apk/res/android"
    xmlns:app="http://schemas.android.com/apk/res-auto">

    <LinearLayout
        android:layout_width="match_parent"
        android:layout_height="wrap_content"
        android:orientation="vertical">

        <include layout="@layout/app_custom_toolbar"/>

        <ScrollView
            android:layout_width="match_parent"
            android:layout_height="wrap_content">
            <LinearLayout
                android:layout_width="match_parent"
                android:layout_height="match_parent"
                android:id="@+id/only_activity"
                android:orientation="vertical"
                android:visibility="visible"
                android:padding="10dp">

                <!-- What we want to show on our activity -->

            </LinearLayout>
        </ScrollView>
    </LinearLayout>

    <android.support.design.widget.NavigationView
        android:id="@+id/nav_view_id"
        android:layout_width="match_parent"
        android:layout_height="match_parent"
        android:layout_gravity="start"
        app:headerLayout="@layout/nav_header_layout"
        app:menu="@menu/nav_menu"
        android:background="#ffffff">
    </android.support.design.widget.NavigationView>

</android.support.v4.widget.DrawerLayout>

<!-- drawer_layout_id, app_custom_toolbar, only_activity, nav_view_id, nav_header_layout, nav_menu, #ffffff -->