add_meta_box()

最后更新于：2021-11-25 19:21:40

add_meta_box( string$id, string$title, callable$callback, string|array|GC_Screen$screen=null, string$context=’advanced’, string$priority=’default’, array$callback_args=null)

Adds a meta box to one or more screens.

参数

$id

(string) (Required) Meta box ID (used in the ‘id’ attribute for the meta box).

$title

(string) (Required) Title of the meta box.

$callback

(callable) (Required) Function that fills the box with the desired content. The function should echo its output.

$screen

(string|array|GC_Screen) (Optional) The screen or screens on which to show the box (such as a post type, ‘link’, or ‘comment’). Accepts a single screen ID, GC_Screen object, or array of screen IDs. Default is the current screen. If you have used add_menu_page() or add_submenu_page() to create a new screen (and hence screen_id), make sure your menu slug conforms to the limits of sanitize_key() otherwise the ‘screen’ menu may not correctly render on your page.

Default value: null

$context

(string) (Optional) The context within the screen where the box should display. Available contexts vary from screen to screen. Post edit screen contexts include ‘normal’, ‘side’, and ‘advanced’. Comments screen contexts include ‘normal’ and ‘side’. Menus meta boxes (accordion sections) all use the ‘side’ context. Global

Default value: ‘advanced’

$priority

(string) (Optional) The priority within the context where the box should show. Accepts ‘high’, ‘core’, ‘default’, or ‘low’.

Default value: ‘default’

$callback_args

(array) (Optional) Data that should be set as the $args property of the box array (which is the second parameter passed to your callback).

Default value: null

源文件

文件: gc-admin/includes/template.php

function add_meta_box( $id, $title, $callback, $screen = null, $context = 'advanced', $priority = 'default', $callback_args = null ) {
	global $gc_meta_boxes;

	if ( empty( $screen ) ) {
		$screen = get_current_screen();
	} elseif ( is_string( $screen ) ) {
		$screen = convert_to_screen( $screen );
	} elseif ( is_array( $screen ) ) {
		foreach ( $screen as $single_screen ) {
			add_meta_box( $id, $title, $callback, $single_screen, $context, $priority, $callback_args );
		}
	}

	if ( ! isset( $screen->id ) ) {
		return;
	}

	$page = $screen->id;

	if ( ! isset( $gc_meta_boxes ) ) {
		$gc_meta_boxes = array();
	}
	if ( ! isset( $gc_meta_boxes[ $page ] ) ) {
		$gc_meta_boxes[ $page ] = array();
	}
	if ( ! isset( $gc_meta_boxes[ $page ][ $context ] ) ) {
		$gc_meta_boxes[ $page ][ $context ] = array();
	}

	foreach ( array_keys( $gc_meta_boxes[ $page ] ) as $a_context ) {
		foreach ( array( 'high', 'core', 'default', 'low' ) as $a_priority ) {
			if ( ! isset( $gc_meta_boxes[ $page ][ $a_context ][ $a_priority ][ $id ] ) ) {
				continue;
			}

			// If a core box was previously removed, don't add.
			if ( ( 'core' === $priority || 'sorted' === $priority )
				&& false === $gc_meta_boxes[ $page ][ $a_context ][ $a_priority ][ $id ]
			) {
				return;
			}

			// If a core box was previously added by a plugin, don't add.
			if ( 'core' === $priority ) {
				/*
				 * If the box was added with default priority, give it core priority
				 * to maintain sort order.
				 */
				if ( 'default' === $a_priority ) {
					$gc_meta_boxes[ $page ][ $a_context ]['core'][ $id ] = $gc_meta_boxes[ $page ][ $a_context ]['default'][ $id ];
					unset( $gc_meta_boxes[ $page ][ $a_context ]['default'][ $id ] );
				}
				return;
			}

			// If no priority given and ID already present, use existing priority.
			if ( empty( $priority ) ) {
				$priority = $a_priority;
				/*
				 * Else, if we're adding to the sorted priority, we don't know the title
				 * or callback. Grab them from the previously added context/priority.
				 */
			} elseif ( 'sorted' === $priority ) {
				$title         = $gc_meta_boxes[ $page ][ $a_context ][ $a_priority ][ $id ]['title'];
				$callback      = $gc_meta_boxes[ $page ][ $a_context ][ $a_priority ][ $id ]['callback'];
				$callback_args = $gc_meta_boxes[ $page ][ $a_context ][ $a_priority ][ $id ]['args'];
			}

			// An ID can be in only one priority and one context.
			if ( $priority !== $a_priority || $context !== $a_context ) {
				unset( $gc_meta_boxes[ $page ][ $a_context ][ $a_priority ][ $id ] );
			}
		}
	}

	if ( empty( $priority ) ) {
		$priority = 'low';
	}

	if ( ! isset( $gc_meta_boxes[ $page ][ $context ][ $priority ] ) ) {
		$gc_meta_boxes[ $page ][ $context ][ $priority ] = array();
	}

	$gc_meta_boxes[ $page ][ $context ][ $priority ][ $id ] = array(
		'id'       => $id,
		'title'    => $title,
		'callback' => $callback,
		'args'     => $callback_args,
	);
}

/**
 * Calls the class on the post edit screen.
 */
function call_someClass() {
	new someClass();
}

if ( is_admin() ) {
	add_action( 'load-post.php',     'call_someClass' );
	add_action( 'load-post-new.php', 'call_someClass' );
}

/**
 * The Class.
 */
class someClass {

	/**
	 * Hook into the appropriate actions when the class is constructed.
	 */
	public function __construct() {
		add_action( 'add_meta_boxes', array( $this, 'add_meta_box' ) );
		add_action( 'save_post',      array( $this, 'save'         ) );
	}

	/**
	 * Adds the meta box container.
	 */
	public function add_meta_box( $post_type ) {
		// Limit meta box to certain post types.
		$post_types = array( 'post', 'page' );

		if ( in_array( $post_type, $post_types ) ) {
			add_meta_box(
				'some_meta_box_name',
				__( 'Some Meta Box Headline', 'textdomain' ),
				array( $this, 'render_meta_box_content' ),
				$post_type,
				'advanced',
				'high'
			);
		}
	}

	/**
	 * Save the meta when the post is saved.
	 *
	 * @param int $post_id The ID of the post being saved.
	 */
	public function save( $post_id ) {

		/*
		 * We need to verify this came from the our screen and with proper authorization,
		 * because save_post can be triggered at other times.
		 */

		// Check if our nonce is set.
		if ( ! isset( $_POST['myplugin_inner_custom_box_nonce'] ) ) {
			return $post_id;
		}

		$nonce = $_POST['myplugin_inner_custom_box_nonce'];

		// Verify that the nonce is valid.
		if ( ! gc_verify_nonce( $nonce, 'myplugin_inner_custom_box' ) ) {
			return $post_id;
		}

		/*
		 * If this is an autosave, our form has not been submitted,
		 * so we don't want to do anything.
		 */
		if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
			return $post_id;
		}

		// Check the user's permissions.
		if ( 'page' == $_POST['post_type'] ) {
			if ( ! current_user_can( 'edit_page', $post_id ) ) {
				return $post_id;
			}
		} else {
			if ( ! current_user_can( 'edit_post', $post_id ) ) {
				return $post_id;
			}
		}

		/* OK, it's safe for us to save the data now. */

		// Sanitize the user input.
		$mydata = sanitize_text_field( $_POST['myplugin_new_field'] );

		// Update the meta field.
		update_post_meta( $post_id, '_my_meta_value_key', $mydata );
	}


	/**
	 * Render Meta Box content.
	 *
	 * @param GC_Post $post The post object.
	 */
	public function render_meta_box_content( $post ) {

		// Add an nonce field so we can check for it later.
		gc_nonce_field( 'myplugin_inner_custom_box', 'myplugin_inner_custom_box_nonce' );

		// Use get_post_meta to retrieve an existing value from the database.
		$value = get_post_meta( $post->ID, '_my_meta_value_key', true );

		// Display the form, using the current value.
		?>
		<label for="myplugin_new_field">
			<?php _e( 'Description for this field', 'textdomain' ); ?>
		</label>
		<input type="text" id="myplugin_new_field" name="myplugin_new_field" value="<?php echo esc_attr( $value ); ?>" size="25" />
		<?php
	}
}

/**
 * Register meta box(es).
 */
function gcdocs_register_meta_boxes() {
	add_meta_box( 'meta-box-id', __( 'My Meta Box', 'textdomain' ), 'gcdocs_my_display_callback', 'post' );
}
add_action( 'add_meta_boxes', 'gcdocs_register_meta_boxes' );

/**
 * Meta box display callback.
 *
 * @param GC_Post $post Current post object.
 */
function gcdocs_my_display_callback( $post ) {
	// Display code/markup goes here. Don't forget to include nonces!
}

/**
 * Save meta box content.
 *
 * @param int $post_id Post ID
 */
function gcdocs_save_meta_box( $post_id ) {
	// Save logic goes here. Don't forget to include nonce checks!
}
add_action( 'save_post', 'gcdocs_save_meta_box' );

/**
 * Register a meta box using a class.
 */
class GCDocs_Custom_Meta_Box {

	/**
	 * Constructor.
	 */
	public function __construct() {
		if ( is_admin() ) {
			add_action( 'load-post.php',     array( $this, 'init_metabox' ) );
			add_action( 'load-post-new.php', array( $this, 'init_metabox' ) );
		}

	}

	/**
	 * Meta box initialization.
	 */
	public function init_metabox() {
		add_action( 'add_meta_boxes', array( $this, 'add_metabox'  )        );
		add_action( 'save_post',      array( $this, 'save_metabox' ), 10, 2 );
	}

	/**
	 * Adds the meta box.
	 */
	public function add_metabox() {
		add_meta_box(
			'my-meta-box',
			__( 'My Meta Box', 'textdomain' ),
			array( $this, 'render_metabox' ),
			'post',
			'advanced',
			'default'
		);

	}

	/**
	 * Renders the meta box.
	 */
	public function render_metabox( $post ) {
		// Add nonce for security and authentication.
		gc_nonce_field( 'custom_nonce_action', 'custom_nonce' );
	}

	/**
	 * Handles saving the meta box.
	 *
	 * @param int     $post_id Post ID.
	 * @param GC_Post $post    Post object.
	 * @return null
	 */
	public function save_metabox( $post_id, $post ) {
		// Add nonce for security and authentication.
		$nonce_name   = isset( $_POST['custom_nonce'] ) ? $_POST['custom_nonce'] : '';
		$nonce_action = 'custom_nonce_action';

		// Check if nonce is valid.
		if ( ! gc_verify_nonce( $nonce_name, $nonce_action ) ) {
			return;
		}

		// Check if user has permissions to save data.
		if ( ! current_user_can( 'edit_post', $post_id ) ) {
			return;
		}

		// Check if not an autosave.
		if ( gc_is_post_autosave( $post_id ) ) {
			return;
		}

		// Check if not a revision.
		if ( gc_is_post_revision( $post_id ) ) {
			return;
		}
	}
}

new GCDocs_Custom_Meta_Box();

/**
 * This function adds a meta box with a callback function of my_metabox_callback()
 */
function add_gcdocs_meta_box() {
	$var1 = 'this';
	$var2 = 'that';
	add_meta_box(
		'metabox_id',
		__( 'Metabox Title', 'textdomain' ),
		'gcdocs_metabox_callback',
		'page',
		'normal',
		'low',
		array( 'foo' => $var1, 'bar' => $var2 )
	);
}

/**
 * Get post meta in a callback
 *
 * @param GC_Post $post    The current post.
 * @param array   $metabox With metabox id, title, callback, and args elements.
 */

function gcdocs_metabox_callback( $post, $metabox ) {
	// Output last time the post was modified.
	echo 'Last Modified: ' . $post->post_modified;

	// Output 'this'.
	echo $metabox['args']['foo'];

	// Output 'that'.
	echo $metabox['args']['bar'];

	// Output value of custom field.
	echo get_post_meta( $post->ID, 'gcdocs_custom_field', true );
}

function op_register_menu_meta_box() {
    add_meta_box(
        'op-menu-meta-box-id',
        esc_html__( 'Op Menu MetaBox Title', 'text-domain' ),
        'op_render_menu_meta_box',
        'nav-menus',
        'side',
        'core'
        );
}
add_action( 'load-nav-menus.php', 'op_register_menu_meta_box' );

function op_render_menu_meta_box() {
    // Metabox content
    echo '<strong>Hi, I am MetaBox.</strong>';
}

<?php
namespace DevWpNoteMetaBox;

add_action( 'save_post', __NAMESPACE_ . 'save_fields', 10, 3 );
function save_fields( $post_id, GC_Post $post, $update ) {
   // check nonce ...
   // check autosave ... 
   // check user capabilities ...

   // check if there was a multisite switch before
   if ( is_multisite() && ms_is_switched() ) {
      return $post_id;
   }

   // handle your meta box input ...
}

//Register Meta Box
function rm_register_meta_box() {
	add_meta_box( 'rm-meta-box-id', esc_html__( 'RM MetaBox Title', 'text-domain' ), 'rm_meta_box_callback', 'post', 'advanced', 'high' );
}
add_action( 'add_meta_boxes', 'rm_register_meta_box');

//Add field
function rm_meta_box_callback( $meta_id ) {

	$outline = '<label for="title_field" style="width:150px; display:inline-block;">'. esc_html__('Title Field', 'text-domain') .'</label>';
	$title_field = get_post_meta( $meta_id->ID, 'title_field', true );
	$outline .= '<input type="text" name="title_field" id="title_field" class="title_field" value="'. esc_attr($title_field) .'" style="width:300px;"/>';

	echo $outline;
}

//Register Meta box
add_action( 'add_meta_boxes', function() {
	add_meta_box( 'gcdocs-id', 'Social link', 'gcdocs_field_cb', 'post', 'side' );
} );

//Meta callback function
function gcdocs_field_cb( $post ) {
	$gcdocs_meta_val = get_post_meta( $post->ID, 'gcdocs-meta-name', true );
	?>
	<input type="url" name="gcdocs-meta-name" value="<?php echo esc_attr( $gcdocs_meta_val ) ?>">
	<?php
}

//save meta value with save post hook
add_action( 'save_post', function( $post_id ) {
	if ( isset( $_POST['gcdocs-meta-name'] ) ) {
		update_post_meta( $post_id, 'gcdocs-meta-name', $_POST['gcdocs-meta-name'] );
	}
} );

// show meta value after post content
add_filter( 'the_content', function( $content ) {
	$meta_val = get_post_meta( get_the_ID(), 'gcdocs-meta-name', true );
	return $content . $meta_val;
} );

function save_metabox_callback( $post_id ) {

	if ( ! isset( $_POST['nonce'] ) ) {
		return;
	}

	if ( ! gc_verify_nonce( $_POST['nonce'], 'nonce_value' ) ) {
		return;
	}

	if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
		return;
	}

	if ( ! current_user_can( 'edit_post', $post_id ) ) {
		return;
	}

	if ( isset( $_POST['post_type'] ) && 'page' === $_POST['post_type'] ) {

		// do stuff

	}

	// Check if $_POST field(s) are available

	// Sanitize

	// Save
	
}
add_action( 'save_post', 'save_metabox_callback' );

// This will NOT work
add_meta_box( 
	'my_comment_metabox_1',      // ID
	__('My comment metabox 1' ), // Title
	'prefix_comment_metabox',    // Callback
	'comment' 					 // Screen
);
// This WILL work. Same call, but with 'normal' for context instead of default 'advanced'
add_meta_box( 
	'my_comment_metabox_2', 	  // ID
	__('My comment metabox 2' ),  // Title 
	'prefix_comment_metabox', 	  // Callback
	'comment', 					  // Screen
	'normal' 					  // Context
);

class Register_Post_Type
{

    /**
     * Register_Post_Type constructor.
     */
    public function __construct() {
        add_action( "init", array( $this, "register_post_type" ) );
        add_action( "add_meta_boxes", array( $this, "add_mata_box" ) );
        add_action( "save_post", array( $this, "save_mata_date" ) );
    }

    /**
     * Register post type
     */
    public function register_post_type() {
        register_post_type( "newsletter", array(
            "labels"      => array(
                "name"               => esc_html( "Newsletter", "newsletter" ),
                "singular_name"      => esc_html( "Newsletter", "newsletter" ),
                'menu_name'          => esc_html( "Newsletter", "newsletter" ),
                'name_admin_bar'     => esc_html( "Newsletter", "newsletter" ),
                'add_new'            => esc_html( "Add Newsletter", "newsletter" ),
                'add_new_item'       => esc_html( "Add Newsletter", "newsletter" ),
                'new_item'           => esc_html( "New Newsletter", "newsletter" ),
                'edit_item'          => esc_html( "Edit Newsletter", "newsletter" ),
                'view_item'          => esc_html( "View Newsletter", "newsletter" ),
                'all_items'          => esc_html( "All Newsletter", "newsletter" ),
                'search_items'       => esc_html( "Search Newsletter", "newsletter" ),
                'not_found'          => esc_html( "No news found.", "newsletter" ),
                'featured_image'     => esc_html( "Newsletter Cover Image", "newsletter" ),
                'set_featured_image' => esc_html( "Set newsletter image", "newsletter" ),
            ),
            "public"      => true,
            "has_archive" => false,
            "rewrite"     => array(
                "slug" => "newsletter"
            ),
            'menu_icon'   => 'dashicons-book',
            //'supports'    => array( 'title', 'editor', 'author', 'thumbnail', 'excerpt', 'comments' ),
            'supports'    => array( 'title','editor','thumbnail' ),
        ) );
    }

    /**
     * Add post mata box
     */
    public function add_mata_box() {
        add_meta_box( "newsletter_main_post", esc_html( "Add article", "newsletter" ), array( $this, "add_article_html" ), "newsletter", 'advanced' );
    }

    /**
     * Add article html
     */
    public function add_article_html() {
        ?>
        
        <?php
    }

    /**
     * Save mata data
     */
    public function save_mata_date( $post_id ) {
        update_post_meta( $post_id, "add_article_main", array( "adf", "bfdf" ) );
    }
}

/**
 * The Class.
 */
class someClass {
 
    /**
     * Hook into the appropriate actions when the class is constructed.
     */
    public function __construct() {
        add_action( 'add_meta_boxes', array( $this, 'add_meta_box' ) );
        add_action( 'save_post',      array( $this, 'save'         ) );
    }
 
    /**
     * Adds the meta box container.
     */
    public function add_meta_box( $post_type ) {
        // Limit meta box to certain post types.
        $post_types = array('tabs' );
 
        if ( in_array( $post_type, $post_types ) ) {
            add_meta_box(
                'some_meta_box_name',
                __( 'Some Meta Box Headline', 'textdomain' ),
                array( $this, 'render_meta_box_content' ),
                $post_type,
                'advanced',
                'high'
            );
        }
    }
 
    /**
     * Save the meta when the post is saved.
     *
     * @param int $post_id The ID of the post being saved.
     */
    public function save( $post_id ) {
 
        /*
         * We need to verify this came from the our screen and with proper authorization,
         * because save_post can be triggered at other times.
         */
 
        // Check if our nonce is set.
        if ( ! isset( $_POST['myplugin_inner_custom_box_nonce'] ) ) {
            return $post_id;
        }
 
        $nonce = $_POST['myplugin_inner_custom_box_nonce'];
 
        // Verify that the nonce is valid.
        if ( ! gc_verify_nonce( $nonce, 'myplugin_inner_custom_box' ) ) {
            return $post_id;
        }
 
        /*
         * If this is an autosave, our form has not been submitted,
         * so we don't want to do anything.
         */
        if ( defined( 'DOING_AUTOSAVE' ) && DOING_AUTOSAVE ) {
            return $post_id;
        }
 
        // Check the user's permissions.
        if ( 'page' == $_POST['post_type'] ) {
            if ( ! current_user_can( 'edit_page', $post_id ) ) {
                return $post_id;
            }
        } else {
            if ( ! current_user_can( 'edit_post', $post_id ) ) {
                return $post_id;
            }
        }
 
        /* OK, it's safe for us to save the data now. */
 
        // Sanitize the user input.
        $mydata = sanitize_text_field( $_POST['myplugin_new_field'] );
 
        // Update the meta field.
        update_post_meta( $post_id, '_my_meta_value_key', $mydata );
    }
 
 
    /**
     * Render Meta Box content.
     *
     * @param GC_Post $post The post object.
     */
    public function render_meta_box_content( $post ) {
 
        // Add an nonce field so we can check for it later.
        gc_nonce_field( 'myplugin_inner_custom_box', 'myplugin_inner_custom_box_nonce' );
 
        // Use get_post_meta to retrieve an existing value from the database.
        $value = get_post_meta( $post->ID, '_my_meta_value_key', true );
 
        // Display the form, using the current value.
        ?>
        <label for="myplugin_new_field">
            <?php _e( 'Description for this field', 'textdomain' ); ?>
        </label>

        
        <textarea style="width:100%;min-height:200px;" type="textarea" class="form-control" name="myplugin_new_field" ><?php echo esc_attr( $value ); ?></textarea> 
        
        <?php
    }
}


class MyClass{
    
    public function __construct() {
        add_action( 'add_meta_boxes', array( &$this, 'gcdocs_register_meta_boxes' ) );
        // If static
        add_action( 'add_meta_boxes', array( __CLASS__, 'gcdocs_register_meta_boxes_static' ) );
    }
    
    // Singleton
    static function get_instance() {
        static $Inst = null;
        if( $Inst == null ) {
            $Inst = new self();
        }
        
        return $Inst;
    }
    
    public function gcdocs_register_meta_boxes() {
        add_meta_box( 'meta-box-id', __( 'My Meta Box', 'textdomain' ), 'gcdocs_my_display_callback', 'post' );
    }
    
    public function gcdocs_register_meta_boxes_static() {
        add_meta_box( 'meta-box-id', __( 'My Meta Box', 'textdomain' ), 'gcdocs_my_display_callback', 'post' );
    }
    
}

MyClass::get_instance();

function add_meta_box( $id, $title, $callback, $screen = null, $context = 'advanced', $priority = 'default', $callback_args = null ) {
    global $gc_meta_boxes;
 
    if ( empty( $screen ) ) {
        $screen = get_current_screen();
    } elseif ( is_string( $screen ) ) {
        $screen = convert_to_screen( $screen );
    } elseif ( is_array( $screen ) ) {
        foreach ( $screen as $single_screen ) {
            add_meta_box( $id, $title, $callback, $single_screen, $context, $priority, $callback_args );
        }
    }
 
    if ( ! isset( $screen->id ) ) {
        return;
    }
 
    $page = $screen->id;

…

function add_meta_box( $id, $title, $callback, $screen = null, $context = 'advanced', $priority = 'default', $callback_args = null ) {
	global $gc_meta_boxes;

	if ( $screen == null ) {
$screen = GC_Screen::get( );
} elseif ( empty( $screen ) ) {
$screen = get_current_screen();
} elseif ( is_string( $screen ) ) {
$screen = convert_to_screen( $screen );
} elseif ( is_array( $screen ) ) {
foreach ( $screen as $single_screen ) {
add_meta_box( $id, $title, $callback, $single_screen, $context, $priority, $callback_args );
}
}

$page = $screen->id;

…