Incorporating the Settings API in WordPress Themes

Filed in Web DevelopmentTags: Settings API, Themes, tutorials, WordPress

Register Settings and Define Form Sections/Fields

Here, we use the Settings API to register our settings, and to define our Settings page form sections and form fields.

Register Settings

The first step is simple; we register our settings:

register_setting( 'theme_oenology_options', 'theme_oenology_options', 'oenology_options_validate' );
Function: register_setting()

Codex: register_setting()

The register_setting() function associates an option group (the $option_group argument passed to settings_fields() and do_settings_sections(), above) with a database entry and a data-validation callback function.

The register_setting( $option_group, $option_name, $sanitize_callback ) function accepts three arguments:

  • $option_group: the name of the option group. Must be the same as the $option_group defined in settings_fields(). This is the "flag" that ties everything together outside of the database (i.e. within the Settings page)
  • $option_name: the name of the option as stored in the database.
  • $sanitize_callback: the name of the function that holds the data validation and whitelisting

Since we have only one database entry, which is an array that holds all of our options, we only need to call register_setting() once. If we instead had multiple database entries, we would have to call register_setting() once for each database entry.

Note: this function call needs to be hooked into admin_init.

With this simple step out of the way, we now move on to the meat of our Settings API implementation: building out the form sections and form fields.

Define Form Sections and Fields

Separating Settings Per Tab

Our Settings page has multiple tabs, but we only defined one form. We only have one form, and therefore call settings_fields() and do_settings_sections() only once within that form. If you recall, both of these settings have arguments that tie both the database entry (via register_setting()) and the settings sections (via add_settings_section()) to the form.

We want to ensure that the form only outputs/handles the settings applicable to each tab. There are at least two ways to accomplish this separation:

  1. Assign each tab's related options to a separate $option_group and $page, and add a current-tab conditional around the settings_fields() and do_settings_sections() calls.
  2. Assign all options, regardless of tab, to the same $option_group and $page, and add a current-tab conditional around the functions that register the form sections and form fields.

Because it is what I thought of first, I went with the latter option; however, the former option might make a bit more semantic sense (assuming it works; I've not tried it).

Here's how I handled it:

global $pagenow;
if ( 'themes.php' == $pagenow && isset( $_GET['page'] ) && 'oenology-settings' == $_GET['page'] ) :
     if ( isset ( $_GET['tab'] ) ) :
          $tab = $_GET['tab'];
     else:
          $tab = 'general';
     endif;
     switch ( $tab ) :
          case 'general' :
               require( get_template_directory() . '/functions/options-register-general.php' );
               break;
          case 'varietals' :
               require( get_template_directory() . '/functions/options-register-varietals.php' );
               break;
     endswitch;
endif;

Essentially, a separate file is included, depending on which tab is displayed. Each file contains the code that registers the form sections and form fields related to each tab.

The $pagenow global is basically the URL of the current page. When we hooked our Settings page into the admin menu, the add_theme_page() function appends a parameter "page" to the URL, in the form of "page=oenology-options". Our custom function that handles tabs also adds a parameter, "tab", to the URL, in the form of "tab=general". So, if we are on the General tab of our Settings page, the URL would look something like:

http://www.domain.tld/wp-admin/themes.php?page=oenology-settings?tab=general

We take advantage of these URL parameters, via $pagenow, to build our conditional.

Defining Form Sections

Form sections are added via the add_settings_section() function.

Function: add_settings_section()

Codex: add_settings_section()

As its name implies, the add_settings_section() function defines a form section. Sections are simply groupings of (presumably similar/related) form fields. A settings form may have any number of sections. All form fields must be added to form sections.

The add_settings_section( $section, $title, $callback, $page ) function accepts four arguments:

  • $section: the name/id of the section. This argument correlates to the $section argument that is passed to each call to add_settings_field(), and is also passed as the CSS ID selector of the section's containing DIV.
  • $title: the title of the section, as output on the form.
  • $callback: function that contains markup/text to be output with the section, before associated settings fields are output (e.g. to provide explanatory text/description)
  • $page: the name of the Settings page for which to output the section. Must be the same as the $page argument passed to do_settings_sections(), which we addressed previously

We simply add one call to add_settings_section() for each form section.

General Tab

For the General tab, we will define two sections: one for Header options and one for Footer options:

// Add a form section for the Header settings
add_settings_section('oenology_settings_general_header', 'Header Options', 'oenology_settings_general_header_section_text', 'oenology');

// Add a form section for the Footer settings
add_settings_section('oenology_settings_general_footer', 'Footer Options', 'oenology_settings_general_footer_section_text', 'oenology');
Varietals Tab

For our Varietals tab, we will define only one section:

// Add a form section for the Varietal theme settings
add_settings_section('oenology_settings_varietal', 'Oenology Theme Varietals', 'oenology_settings_varietal_section_text', 'oenology');

Adding Form Fields to Sections

Form sections are added via the add_settings_field() function.

Function: add_settings_field()

Codex: add_settings_field()

As its name implies, the add_settings_field() function defines a form field.

The add_settings_field( $field, $title, $callback, $page, $section ) function accepts five arguments:

  • $field: the name/id of the field; also passed as the CSS ID selector of the field's containing DIV.
  • $title: the title of the field, as output on the form.
  • $callback: function that contains markup/text to be output
  • $page: the name of the Settings page for which to output the section. Must be the same as the $pageargument passed to do_settings_sections(), which we addressed previously
  • $section: the name of the form section to which the field is added. This argument correlates to the $section argument that is passed to each call to add_settings_section()
General Tab

For our General tab, we will define three options: two of which will belong to the Header options section, and one of which will belong to the Footer options section:

// Add Header Navigation Menu Position setting to the Header section
add_settings_field('oenology_setting_header_nav_menu_position', 'Header Nav Menu Position', 'oenology_setting_header_nav_menu_position', 'oenology', 'oenology_settings_general_header');

// Add Header Navigation Menu Depth setting to the Header section
add_settings_field('oenology_setting_header_nav_menu_depth', 'Header Nav Menu Depth', 'oenology_setting_header_nav_menu_depth', 'oenology', 'oenology_settings_general_header');

// Add Footer Credit Link setting to the Footer section
add_settings_field('oenology_setting_display_footer_credit', 'Footer Credit', 'oenology_setting_display_footer_credit', 'oenology', 'oenology_settings_general_footer');
Varietals Tab

For our Varietals tab, we will define one option, which will belong to our only defined section:

// Add Varietal setting to the Varietal section
add_settings_field('oenology_setting_varietal', 'Available Varietals', 'oenology_setting_varietal', 'oenology', 'oenology_settings_varietal');

And now that we have defined all of our form sections and fields, we move on to defining the callback functions that (finally!) contain all of the markup that gets output on the Settings page.

Feedback

Comments (Comments are closed)

47 Responses to “Incorporating the Settings API in WordPress Themes”
  1. chip_bennett says:

    Incorporating the Settings API in WordPress Themes – http://www.chipbennett.net/2011/02/17/in… #wordpress

  2. Sayontan says:

    This is an exceptionally detailed tutorial, Chip! Looks like you beat me to it – I had started writing one based on my experience.

    I have grappled with a lot of these concepts while rewriting the options for Suffusion. In my case the situation was more complex – I have 2 levels of tabs: a horizontal one similar to your General / Varietals, and a vertical one within each. So basically I have GUI settings and Back-End Settings, with the first having Header settings, footer settings, fonts etc, and the back-end having tabs for SEO, Analytics etc.

    Also, instead of using one form, I had to use one form for each tab. Otherwise with my number of options I was running into issues with PHP installations that had Suhosin enabled (that restricts the number of post variables). That pushed the complexity to a whole different label, and I had to keep track of post variables in other forms (otherwise the whole array gets rewritten to only have options from the current form). Anyway, I guess you can see what I am saying when I submit my next version for review.

    One small note – in page 3 you are retrieving “settings-updated”. That applies to WP 3.1 onwards. In WP 3.0 you get “updated” as the returned URL parameter.

  3. chip_bennett says:

    Incorporating the Settings API in WordPress Themes – http://www.chipbennett.net/2011/02/17/in… #wordpress – I don’t do this often, but: please RT

  4. chip_bennett says:

    Incorporating the Settings API in WordPress Themes – http://www.chipbennett.net/2011/02/17/in… #wordpress – I don’t do this often, but: please RT

  5. Hi Chip,

    Great (and comprehensive!) tutorial here! One thing I had to find out the hard way: if you use the Settings API, you need the ‘manage_options’ capability to update the options. Normally this works fine, as only administrators have those two capabilities, but if you give editors the ability to edit theme options, they’ll need ‘manage_options’ too. This is built into the settings api, since it’s assumed it’s going to be used for options pages.

    Cheers!
    -John

  6. Chip Bennett says:

    @John P. Bloch

    Are you 100% certain that you are unable to use the edit_theme_options capability with add_theme_page()? I can confirm that I have used it with no problems whatsoever, and edit_theme_options is the capability officially recommended by the WordPress Theme Review Team and far-more-expert-than-I Theme developers such as Justin Tadlock.

  7. jonnyjaniero says:

    huge thanks for this. shines a big beam of light on the whole process.

  8. Looks like a fantastic tutorial.
    I didn’t read it yet, since now is not a good time for me to do this and so I wanted to print out the whole tutorial which sadly didn’t work.
    Not even using the print button to print individual pages worked but cropped content on each article.
    So I have to come back another time or cut and paste each part individually.
    Nevertheless, I think it will be worth it an am very greatful for this tutorial.

  9. Chip Bennett says:

    Christian:

    Check the post pagination links at the bottom of the post. I added an “all” link, that will output the entire post on a single page – specifically so that this post could be printed. Let me know if it’s not working for you!

  10. Rilwis says:

    Hi,

    I’ve read your article, and follow most of it. But I have a problem with tabs. As you said, you haven’t tried 2 options for tabs that handle form fields which are in current tabs. Sadly, when I update the form, only fields in current tab are save, fields in other tabs are ignored.

    I’m thinking that WP don’t automatically recognize tabs and save them. We need to do it ourselves. Do you know how to make it easily?

  11. Chip Bennett says:

    @Rilwis:

    I’m sorry; I’m not exactly following your question.

    The method that I describe here separates, via PHP, the form fields on one tab from the form fields on other tabs. When viewing one tab, the form fields on other tabs are never called. They don’t currently exist on the page. So, it is true: WordPress doesn’t save any settings not on the current page, because at the current point in time, WordPress doesn’t load the fields that allow those other settings to be modified.

    To do something different, such as loading all the settings on a single page, and then separate them via tabs, you’d have to take an entirely different approach (such as using jQuery to show/hide groups of settings).

  12. Sayontan says:

    @Chip, @Rilwis,
    How I handled this is by invoking the hidden fields in the validation function itself. Basically if you have separate forms you tend to lose the settings of other forms unless you have them conveyed to the back-end. Since you are anyway constructing the forms based on information you have in the back-end, it is easy to pull up the options from other screens in the validation function without passing them at form submission.

    Moreover I prefer passing it through the validation function because that keeps your form lighter.

  13. Rilwis says:

    @Chip,
    Sorry if I didn’t say clearly. Sayontan said exactly what I meant.

    It seems that the validation function is a good solution here. I’ll try it.

  14. Tobias says:

    Thanks, very useful tutorial!

  15. newbiewpcoder says:

    how can i display a message based on which button has been clicked for example if i click reset i would like it to display a message saying “settings reset” also like Sayontan says i had to change “settings-updated” to “updated” within the form code as it didn’t show the message “settings saved” when i clicked save settings

  16. Chip Bennett says:

    @newbiewpcoder:

    I’ll get back to you on your first question.

    Regarding your second question, by some point this morning (hopefully), you’ll need to use settings-updated, rather than updated. 😉

  17. newbiewpcoder says:

    thanks for this tutorial i’m building an options page using this method and trying to move all my old options over to this but i cannot get multi-select checkboxes to save as i have some older code to grab all pages into an array created in wordpress like

    $pages_array = get_pages('hide_empty=0');

    $site_pages = array();

    foreach ($pages_array as $pagg) {
    $site_pages[$pagg->ID] = $pagg->post_title;
    $pages_ids[] = $pagg->ID;
    }

    function oenology_get_default_options() {
    $options = array(
    'header_nav_menu_position' => 'top',
    'header_nav_menu_depth' => 1,
    'display_footer_credit' => false,
    'varietal' => 'cuvee',
    'menu_pages' => $pages_ids

    );
    return $options;
    }

  18. @Chip

    (Sorry for the delayed response)
    ‘edit_theme_options’ for the theme page is fine. It’s the Settings API that requires the ‘manage_options’ capability. The settings API requires you to send form data to /wp-admin/options.php, which, on lines 30-31 has this code:

    if ( !current_user_can('manage_options') )
    wp_die(__('Cheatin’ uh?'));

    The theme options page that this code creates will work without a problem, and saving the content will work without a problem — most of the time.

    The case where it doesn’t work is when you have anybody who can edit theme options but cannot manage options.

    For example, I program clients’ sites with a non-standard ‘Admin Lite’ role which is an editor that can create, edit, and delete non-Administrator users, as well as manage theme options. Because of the way options.php handles capabilities, I cannot use the settings API to validate or save the data from my theme options page. These are very specific use cases, and it might help to know about this behavior for anybody looking up this tutorial in the future. Just trying to share some hard-won knowledge in case it’s useful. 🙂

    -John

  19. newbiewpcoder says:

    you can delete my last comment as i managed to solve it myself, i have created a function to return each option here’s the function

    function theme_get_option($name) {
    $options = get_option('theme_oenology_options');
    if (isset($options[$name])) {
    return $options[$name];
    } else {
    return false;
    }
    }

    example of usage

    of course you may not want to echo the option but you get the idea

  20. newbiewpcoder says:

    oops my code was cut off here it is

    echo theme_get_option('display_footer_credit');

  21. Thijs says:

    Thank you for this detailed tutorial, very helpful! One thing I would like to know is if it is possible to do an ajax save when using the Settings API. I know how to do this when using standard options, but I have not come across a way that shows how to do this with the settings API.

    Thanks for your help!

    Thijs.

  22. Mamaduka says:

    Hello Chip.

    Great tutorial. I followed example and created options page, but I can’t save options. Any idea what can cause this?

    Thanks

    George

  23. enchance says:

    Hi Chip, I know it’s asking too much but is it possible to make a version of this tutorial which does things from scratch instead of lifting code from the Oenology Theme? That way other developers (like myself) can easily integrate it into their own themes since the one here is a bit confusing.

  24. Chip Bennett says:

    @enchance:

    I’m not sure how I could make a more from-scratch tutorial. I added options to Oenology specifically with creating this tutorial in mind.

    What would you like to see done differently?

  25. enchance says:

    Thanks for your reply.

    It started to get pretty confusing by the 5th page and was a bit overwhelmed when a looked at options-register-general.php and options-register-varietal.php files. You’re really a master at this and I commend you for your skill.

    Maybe you can write a “Lite” version of the tutorial which people can build on? Something from the ground up would really be best, that way it’s easier to follow and can be ported to any theme.

  26. Chip Bennett says:

    A “Lite” version is a good idea. I’ve thought of doing something like that, for implementing less-complex Theme Options schemes.

    Let me see what I can do!

    (Note: I wrote the tutorial with the assumption that the reader could easily follow the files, via the GitHub repository. I setup the file structure intentionally, so that anyone using the Oenology files as an example/reference while developing a Theme could easily follow what was happening.)

  27. enchance says:

    Great! I’ll be looking forward to it.

  28. Ken Newman says:

    Hi Chip,

    John P. Bloch is correct in his comment: When using the Settings API, the form action goes to options.php which checks ‘manage_options’ (and in MultiSite also checks is super admin). The capability check in the add_*_page functions is only for whether to show the page in the menu. (This is because you can add a page and post to itself, handling the cap checks manually.) So basically, when using the Settings API, the checks are particularly strict. A user with ‘edit_theme_options’ but not ‘manage_options’ will see the page, but on submit, will get the “Cheatin’ Eh?” error message.

    This is a super tutorial, Thanks Chip, I picked up quite a bit!

    WraithKenny (Ken Newman)

  29. enchance says:

    In case you’re already writing the “Lite” version of this post, what really differentiates this from the other posts is how it shows you how to insert tabs to your theme settings using the latest Settings API.

  30. Hi! Great tutorial, thanks so much for doing it 🙂 It certainly shed some light on how the Settings API works, which was anything but obvious…

    I never managed to get checkboxes working properly until I saw this simpler tutorial. Whew, checkboxes are always a nightmare! Using the Options API I used to avoid them like the plague…

    A stupid question… when using the code for emitting the “Settings saved” banner, I got it displayed… twice. So I’ve just deleted that bit of code and tested it on a different site as well. Apparently, the Settings API already deals with this! Now my question is, if I want to personalise that banner somehow (saying, for instance, what settings have been changed…) how would I change it? Is there a registration function for this? I see there is an (undocumented) add_settings_error() function, I wonder what it does?

    Anyway, thanks so much for pointing me in the right direction!

  31. Very thorough and informative tutorial. Guided me nicely as I coded my first Theme Settings page. Thank you very much, Mr Bennett.

  32. indam says:

    Nice tutorial, I’ve tried it. Is it permissible to
    apply for my free theme?

  33. Thomas says:

    Hey Chip,

    I’ve used your tutorial for adding a reset option to my Theme Options, which works great! I just have one issue now with submitting textarea fields.

    Here is what is happening. I can add in HTML in the text field fine. But, let’s say I want to remove the HTML and then save. My code must not be quite right, because whenever I save, it reverts back to the code that was in there before. Here is what I have to validate the input:

    $validated_input['inline_header_scripts'] = ( '' != $input['inline_header_scripts'] ? trim( $input['inline_header_scripts'] ) : $validated_input['inline_header_scripts'] );

    What do I need to change to make sure I can do this?

    Thanks in advance!

    On a side note, how can I set this textarea to strip out any text that is not within an HTML tag? I haven’t figured that one out yet 🙂

  34. Jan says:

    Thanks for writing this great tutorial. It is about time the new best practise examples and tuts surface in search engines. Where is the tip jar?!
    Best, Jan

  35. Nicolas says:

    I was looking for a tutorial using add_settings_error() in the validation function. Looks like it’s not possible with the Settings API. I guess I will validate also client side to display errors in the form.

    Your tutorial is great.

  36. Boris says:

    Hello Chip,

    I am having difficulty adding image upload fields to these forms. Do you know of a tutorial that covers this?

  37. Jim W says:

    Chip,

    Thanks very much for this very in depth tutorial!

    But, I’ve been trying to find an answer to the issue that John Block mentioned about the superadmin user role and the Settings API. What wasn’t answered was what the workaround is for this issue.

    I’m trying to create a theme for multisite based off of TwentyEleven and I want users to be able to add their personal information on a theme options page, which will them populate into a page template, basically an about me page. None of my users will be superadmins.

    What would be the best way to get around this issue?

    Jim

  38. Markovich says:

    This is extremely detailed and all a bit over my head. All I want is a drop down menu on one of my navigation tabs, like you are implementing at the top of your page. Is there an easier way to go about this?

    Thanks.

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