How to Create a Simple and Dynamic Navigation Menu in WordPress

https://www.wpbeginner.com/wp-themes/how-to-add-custom-navigation-menus-in-wordpress-3-0-themes/
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How to Add Custom Navigation Menus in WordPress Themes

Creating Custom Navigation Menus in WordPress Themes
To add a custom navigation menu, the first thing you need to do is register your new navigation menu by adding this code to your theme’s functions.php file.

function wpb_custom_new_menu() {
  register_nav_menu('my-custom-menu',__( 'My Custom Menu' ));
}
add_action( 'init', 'wpb_custom_new_menu' );

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function wpb_custom_new_menu() {
  register_nav_menus(
    array(
      'my-custom-menu' => __( 'My Custom Menu' ),
      'extra-menu' => __( 'Extra Menu' )
    )
  );
}
add_action( 'init', 'wpb_custom_new_menu' );

You will need to add this code in your theme’s template file where you want to display your menu.


<?php
wp_nav_menu( array( 
    'theme_location' => 'my-custom-menu', 
    'container_class' => 'custom-menu-class' ) ); 
?>


You can use the CSS class .custom_menu_class to style your menu by adding custom CSS code. Here is a sample CSS to help you get started:

div.custom-menu-class ul {
    margin:20px 0px 20px 0px;
    list-style-type: none;
    list-style: none;
    list-style-image: none;
    text-align:right;
    display:inline-block;   
}
div.custom-menu-class li {
    padding: 0px 20px 0px 0px;
    display: inline-block;
} 
 
div.custom-menu-class a { 
    color:#000;
}





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Step 1: Register Custom Navigation Menu

Which Files Will Be Needed for Modification?
functions.php – To register the menu
template file – To display the menu

register_nav_menu('primary-header-menu',__( 'Header Menu' ));

in this example, we are registering the primary header menu. We can also register multiple menus at a time.

register_nav_menus(array(
    'primary' => __('Primary Menu', 'My_First_WordPress_Theme'),
    'secondary' => __('Secondary Menu',       'My_First_WordPress_Theme'),
    'My_custome_menu' => __('finally Menu', 'My_First_WordPress_Theme')
));

Step 2: Display the Custom Navigation Menu

We can display a custom navigation menu the menu in footer than we will need to override the footer.php

wp_nav_menu( array( 'theme_location' => 'primary' ) );

Step 3: Style the Custom Navigation Menu
If we want a specific look for the website we can style the navigation menu by referencing custom CSS classes in the wp_nav_menu function call in the previous step.

wp_nav_menu( array( 'theme_location' => 'primary', 'container_class' => 'my_css_class' ) );