Creating custom post type with custom taxonomy and custom fields programatically

Question

I need to create a custom post type. This post type will have a custom taxonomy. Also this post type will have custom fields.

I dont want to use any plugins to do it, i want to include the creation in a custom plugin.

Although i can generate custom post type and custom taxonomies , i cant find a way to create the custom fields.

1. Custom post type depends on custom taxonomy and vice versa ( "Link to taxonomies" , "Link to post types"). How i create them with their dependancies between them?
2. How to create my custom fields for the new post type programatically?

Answer 1

Create Custom Post Type

function create_product()
{
   $labels = array(
    'name'               => _x( 'Product', 'post type general name', 'stacy' ),
    'singular_name'      => _x( 'product', 'post type singular name', 'stacy' ),
    'menu_name'          => _x( 'Products', 'admin menu', 'stacy' ),
    'name_admin_bar'     => _x( 'Product', 'add new on admin bar', 'stacy' ),
    'add_new'            => _x( 'Add New', 'product', 'stacy' ),
    'add_new_item'       => __( 'Add New Product', 'stacy' ),
    'new_item'           => __( 'New Product', 'stacy' ),
    'edit_item'          => __( 'Edit Product', 'stacy' ),
    'view_item'          => __( 'View Product', 'stacy' ),
    'all_items'          => __( 'All Product', 'stacy' ),
    'search_items'       => __( 'Search Product', 'stacy' ),
    'not_found'          => __( 'No Product found.', 'stacy' ),
    'not_found_in_trash' => __( 'No Product found in Trash.', 'stacy' )
);
   $args = array(
    'labels'             => $labels,
    'description'        => __( 'Description.', 'Add New Product on stacy' ),
    'public'             => true,
    'publicly_queryable' => true,
    'show_ui'            => true,
    'show_in_menu'       => true,
    'query_var'          => true,
    'rewrite'            => array( 'slug' => 'product' ),
    'has_archive'        => true,
    'hierarchical'       => false,
    'menu_position'      => 100,
            'menu_icon'          =>'dashicons-cart',
    'supports'           => array( 'title', 'editor', 'author', 'thumbnail','comments','capabilities' ),
            'taxonomies'         => array('product_category','product_tag')
);
    register_post_type( 'product', $args );
 }
 add_action( 'init', 'create_product' );

Create Custom Metabox and Display meta value on edit post

  function add_product_details_meta_box()
  {
   global $wpdb;
   global $post;
   $custom = get_post_custom( $post->ID );
   <p>
    <label>Short Description:</label><br />
    <textarea rows="5" name="short_description" class="width99"><?= @$custom["short_description"][0] ?></textarea>
   </p> 
   <p>
    <label>Price:</label><br />
            <input type="text" name="price" value="<?= @$custom["price"][0] ?>" class="width99" />
   </p>

    <p>
    <label>Dimensions (in):</label><br />
            <input type="text" name="length" value="<?= @$custom["length"][0] ?>" class="s" placeholder="Length"/>
    </p>
    <p>
    <label>Shipping Lead Days:</label><br />
            <input type="text" name="ship_lead_days" value="<?= @$custom["product_ship_lead_days"][0] ?>" class="s" placeholder="Shipping Lead Days"/>
    </p>
    <p>
    <label>Commision:</label><br />
            <input type="text" name="commision_broker" value="<?= @$custom["commision_broker"][0] ?>" class="s" placeholder="Enter Your Commision Here"/>
    </p>
   }
  add_action( 'admin_init', 'add_product_meta_boxes' );

Update Post Meta

function save_product_custom_fields(){
 global $post;

 if ( $post )
 {
   update_post_meta($post->ID, "short_description", @$_POST["short_description"]);
  update_post_meta($post->ID, "price", @$_POST["price"]);
  update_post_meta($post->ID, "length", @$_POST["length"]);
       update_post_meta($post->ID,'product_ship_lead_days',@$_POST['ship_lead_days']);
 update_post_meta($post->ID,'commision_broker',@$_POST['commision_broker']);
  }
}
add_action( 'save_post', 'save_product_custom_fields' );

Custom Taxonomy Code

add_action( 'init', 'product_category', 0 );
function product_category() {
$labels = array(
    'name'              => _x( 'Categories', 'taxonomy general name' ),
    'singular_name'     => _x( 'category', 'taxonomy singular name' ),
    'search_items'      => __( 'Search Categories' ),
    'all_items'         => __( 'All Categories' ),
    'parent_item'       => __( 'Parent Categories' ),
    'parent_item_colon' => __( 'Parent Categories:' ),
    'edit_item'         => __( 'Edit Categories' ),
    'update_item'       => __( 'Update Categories' ),
    'add_new_item'      => __( 'Add New Category' ),
    'new_item_name'     => __( 'New Category Name' ),
    'menu_name'         => __( 'Categories' ),
  );

   $args = array(
    'hierarchical'      => true,
    'labels'            => $labels,
    'show_ui'           => true,
    'show_admin_column' => true,
    'query_var'         => true,
    'rewrite'           => array( 'slug' => 'product_category' ),
);
register_taxonomy( 'product_category', array( 'product' ), $args );

$labels = array(
    'name'                       => _x( 'Tag', 'taxonomy general name' ),
    'singular_name'              => _x( 'tag', 'taxonomy singular name' ),
    'search_items'               => __( 'Search tag' ),
    'popular_items'              => __( 'Popular tag' ),
    'all_items'                  => __( 'All tag' ),
    'parent_item'                => null,
    'parent_item_colon'          => null,
    'edit_item'                  => __( 'Edit tag' ),
    'update_item'                => __( 'Update tag' ),
    'add_new_item'               => __( 'Add New tag' ),
    'new_item_name'              => __( 'New tag Name' ),
    'separate_items_with_commas' => __( 'Separate tag with commas' ),
    'add_or_remove_items'        => __( 'Add or remove tags' ),
    'choose_from_most_used'      => __( 'Choose from the most used tags' ),
    'not_found'                  => __( 'No tag found.' ),
    'menu_name'                  => __( 'Tags' ),
);

$args = array(
    'hierarchical'          => FALSE,
    'labels'                => $labels,
    'show_ui'               => true,
    'show_admin_column'     => true,
    'update_count_callback' => '_update_post_term_count',
    'query_var'             => true,
    'rewrite'               => array( 'slug' => 'product_tag' ),
);

register_taxonomy( 'product_tag', 'product', $args );
}