Usage of call back function of add_meta_box()

You shouldn’t.

To get the data for the correct post you should be using the $post variable passed to the callback function. This represents the post being edited. Therefore to get the metadata for the correct post you should call get_post_meta() inside the callback function.

Related Posts:

  1. add_meta_boxes action with refresh on save
  2. Save selected item from dropdown menu in a meta box as a metadata value for a custom post type
  3. Second select list values are not saved after clicking update
  4. Saving metabox repeatable fields
  5. OOP Plugin Development. Including external object
  6. How to select the contents in the text view textrea in wp_editor?
  7. Remove metabox from WordPress menu editor page?
  8. How to make my custom widget appear within WordPress widgets? Plugin development
  9. Extend Woocommerce Widget Class – WC_Widget_Product_Categories
  10. Undefined method class::construct() when creating a plugin
  11. Cant register rest routs from class instance
  12. Using admin-post.php for admin form but it directs me to admin-post.php white screen
  13. How do I make this Metabox show current DB value?
  14. Call to “admin_notices” hook from a static method
  15. Save custom field on WP_List_Table
  16. Get value of submit button in custom post type
  17. defined (‘ABSPATH’) false after AJAX post to other PHP-file
  18. PHP calling function within a class
  19. Save data of select list after clicking save
  20. How to execute add_action() function from custom plugin to Crontrol plugin or do_action()?
  21. Issues separating my Plugin pages into different files
  22. How do I change the Go To Categories link in the term_updated_messages
  23. Trouble with WordPress Settings API: Form Submits When Fields Called Directly, Fails When Using Callbacks
  24. How can I catch WordPress custom settings page slug has already changed?
  25. Should I use spl_autoload_register() in my plugin?
  26. How can I save a multiple select array with the settings API for a plug-in options page?
  27. Using register_activation_hook in classes
  28. Does an activated plugin automatically mean its methods are available to other WP functions?
  29. Is there a way for a plugin to add an attribute to the tag of a theme?
  30. Metabox repeating fields – radio buttons not saving correctly
  31. Gutenberg Blocks doesn’t render correctly when using do_blocks
  32. Admin Media grid view images won’t load
  33. Site Title and Tagline in Pagelines DMS Options Panel
  34. My shortcode is showing up twice
  35. Database “Migration” for Plugins?
  36. Does wp-cron runs all tasks scheduled at same time together or one after other?
  37. Making Quote Plugin more efficient
  38. How do I use the Simple HTML DOM Parser in plugin when other plugin already uses it?
  39. Will simple function names in a class structure conflict with other plugins?
  40. Instantiate class to be available to all plugin functions
  41. How to test nonce with AJAX – Plugin development
  42. WP nonce invalid
  43. Custom filter in admin edit custom post type responding with invalid post type?
  44. How can i upload images in an admin page?
  45. How to access global variable $menu inside a class function
  46. Can I prevent the user from adding more than two levels deep of terms inside of a taxonomy metabox?
  47. Unreadable pagination
  48. remove wp floating submenu in wp dashboard
  49. My custom wp-admin php files stopped working
  50. Retrieve $_POST data submitted from external URL in WordPress(NOT API)
  51. How to upload a file to a folder named after the user_id via plugin
  52. Reprinting tags with all attributes
  53. Need Help Fixing My Iframes [closed]
  54. Cannot access wp-admin/wp-login.php (WordPress backend) anymore, what could be wrong?
  55. Update results, Before deleting the related category [closed]
  56. adjust section according to country?
  57. Adding function to Genesis genesis_header [closed]
  58. Trying to retrieve post meta
  59. Custom plugin settings link doesn’t append current class to menu item when visited? Why?
  60. How can I open up my administrative panel to everyone?
  61. Illegal string offset in PHP function
  62. How to hook code to show after the_content?
  63. Using and saving custom dropdown boxes on user profiles
  64. Problem with AJAX in wordpress plugin
  65. Override Admin menu icon
  66. Hooks for post saving make a post-new.php to load latest post’s data
  67. How can I display Custom Post type Custom Columns and its Content in a Dashboard Widget?
  68. custom plugin with upload files does not work
  69. What is the difference between Null vs Empty (Zero Length) string?
  70. Aspx/Rss feed – failed to open stream: Redirection limit reached
  71. send popup after wp_redirect()
  72. no_rest_route error on custom routes
  73. Checkbox doesn’t save inside metabox
  74. Adding image upload in tag section – WordPress plugin development
  75. Create ACF Checkbox to get all ACF Values from Parent Page
  76. File is executed twice if plugin is activating
  77. product_type_options get saved value [closed]
  78. Display a custom name when the user has no name settle in his account
  79. Sum All the Post Meta of Published posts of Current Logged in user
  80. How do I remove an action hook inside a class that is called by another class?
  81. Get post content inside plugin class method
  82. Autoloading Classes in Plugins
  83. Admin backend, show post from a category and exclude the posts from subcategories
  84. Right way to display the_author_meta fields?
  85. Use page-templates without creating theme
  86. Comparing Dates within plugin using PHP If statement
  87. Submit to itself don’t work
  88. Singleton plugin activation; create database
  89. custom field meta-box with dropdown/autocomplete
  90. Repeatable field within repeatable group of fields
  91. How to get WordPress Adminmenu items?
  92. How to callback custom field text
  93. How keep woocommerce users separeted in multisite install and keep admins on network
  94. Import users and custom user meta from csv
  95. Prevent users from display default wordpress login form
  96. Create custom table for wordpress custom registration flow
  97. Warning: Illegal string offset ‘post’ and ‘page’
  98. Authenticate + Authorize WP REST API request before built-in WP JSON Schema Payload Validation?
  99. WordPress wp_set_object_terms does not assign product to custom taxonomy
  100. How to Customize the Admin Sidebar Menu in WordPress Multisite Network by changing the backend code of the wp-admin code files?