Customizer Theme Switcher Feature Plugin Merge Proposal

Ticketticket Created for both bug reports and feature development on the bug tracker.: #31303

Customizer Theme Switcher brings theme-browsing and theme-switching functionality into the CustomizerCustomizer Tool built into WordPress core that hooks into most modern themes. You can use it to preview and modify many of your site’s appearance settings.. By integrating themes directly into the Customizer, live-previewing workflows are greatly simplified, and the relationship between themes and theme/site options is clarified for the user.

This pluginPlugin A plugin is a piece of software containing a group of functions that can be added to a WordPress website. They can extend functionality or add new features to your WordPress websites. WordPress plugins are written in the PHP programming language and integrate seamlessly with WordPress. These can be free in the WordPress.org Plugin Directory https://wordpress.org/plugins/ or can be cost-based plugin from a third-party represents a significant step in moving all “Appearance” functionality into the Customizer, following Widgets. The future roadmap includes Menus, Theme-Install, and iterations on widgets that would allow the Customizer to entirely replace those adminadmin (and super admin) screens for most users. Because the Customizer Theme Switcher plugin does not address theme-install, the admin page (themes.php) is fully intended to remain in use for now. We are proposing to redirect the front-end “Themes” link (in the admin bar) to the Customizer, as was done for widgets in 4.1.

Technical Overview

Customizer Theme Switcher is primarily about adding new UIUI User interface for existing functionality using existing APIs, rather than introducing new functionality. The plugin operates entirely off of the WordPress 4.1 Customizer APIAPI An API or Application Programming Interface is a software intermediary that allows programs to interact with each other and share data in limited, clearly defined ways., leveraging the new JavaScriptJavaScript JavaScript or JS is an object-oriented computer programming language commonly used to create interactive effects within web browsers. WordPress makes extensive use of JS for a better user experience. While PHP is executed on the server, JS executes within a user’s browser. https://www.javascript.com/. API in particular. Themes is a custom section (that acts kind of like a panel). Each theme is a custom Customizer control.

The code is heavily Backbone.js-inspired, leveraging JSJS JavaScript, a web scripting language typically executed in the browser. Often used for advanced user interfaces and behaviors.-heavy portions of the Customizer API to do things like underscore JS templates for rendering theme data. Most of the code is directly adapted from the Backbone-driven themes.php system (and the theme data is retrieved with existing functions), but things like the search/filterFilter Filters are one of the two types of Hooks https://codex.wordpress.org/Plugin_API/Hooks. They provide a way for functions to modify data of other functions. They are the counterpart to Actions. Unlike Actions, filters are meant to work in an isolated manner, and should never have side effects such as affecting global variables and output. are written from the ground up to leverage the Customizer API (in that case, conditionally activating/deactivating controls).

In keeping with the goal to avoid back-end functionality changes, theme-switches are accomplished simply by leveraging the existing ability to pass a theme as a URLURL A specific web address of a website or web page on the Internet, such as a website’s URL www.wordpress.org query arg when loading the Customizer; ie, the Customizer is simply reloaded to preview a different theme. Loading overlays are leveraged to make this process seem more instant. Unrelated 4.2 coreCore Core is the set of software required to run WordPress. The Core Development Team builds WordPress. work around Customizer Transactions could potentially improve how this works.

Core Changes & Merge Implementation Details

As outlined in the plugin’s readme there are several proposed technical and user-oriented changes that are best done as core patches (mostly in the merge patchpatch A special text file that describes changes to code, by identifying the files and lines which are added, removed, and altered. It may also be referred to as a diff. A patch can be applied to a codebase for testing.):

UXUX User experience

  • Remove #customize-info for theme previews.
  • Change front-end admin bar Themes link to point to themes in the Customizer (deep-linked).
  • When a new theme is activated, go to the home page (front end), not the themes admin.
  • If user doesn’t confirm that they want to leave unsaved changes, remove the customize-loading body class (requires core patch).

Code

  • Move custom section and control to class-wp-customize-control|section.php in wp-includes.
  • Merge all CSSCSS Cascading Style Sheets. into customize-controls.css, scope to .wp-customizer.
  • Move .themes-panel-back to the Customizer headerHeader The header of your site is typically the first thing people will experience. The masthead or header art located across the top of your page is part of the look and feel of your website. It can influence a visitor’s opinion about your content and you/ your organization’s brand. It may also look different on different screen sizes., adjust JS accordingly.
  • Merge JS into customizer-controls.js, after the respective object types.
  • Merge customize_themes_template() into wp-admin/includes/theme.php, at the very end. Make sure that this file is included at the appropriate time as needed when adding the Customizer controls.
  • Merge remaining PHPPHP The web scripting language in which WordPress is primarily architected. WordPress requires PHP 5.6.20 (all in Customize Register callback) into register_controls() in class-wp-customize-manager.php.

User Testing

@designsimply has run four usertesting.com tests (see links in #core-customize), and we haven’t really seen any ongoing issues with the actual theme switcher. It has been difficult to get users to follow our instructions, but when they have used the themes-in-Customizer UI, the interactions have been fairly seamless and as-intended. Further testing could be beneficial after merge, but we think that in-person testing and feedback is generally going to be more effective for this particular plugin.

Outstanding Issues

The exact handling of the themes header display still needs some work – the backwards-sliding works well but the arrows to indicate it don’t. @folletto opened a ticket on core tracTrac An open source project by Edgewall Software that serves as a bug tracker and project management tool for WordPress. to work through some alternative options. Most of the accessibilityAccessibility Accessibility (commonly shortened to a11y) refers to the design of products, devices, services, or environments for people with disabilities. The concept of accessible design ensures both “direct access” (i.e. unassisted) and “indirect access” meaning compatibility with a person’s assistive technology (for example, computer screen readers). (https://en.wikipedia.org/wiki/Accessibility) issues have been fixed as well (@afercia please let me know if I’ve missed any), with the exception of the Themes section header, which will happen along with the UI changes there for everyone.

Future Plans

A future phase of this project will explore integrating theme-install in the Customizer and minimizing the distinction between installed and available themes. Due to the larger UI and UX changes proposed with that effort, we’ve decided to hold off on theme-install for now so that the basic theme-switching functionality could be built on a reasonable timeline for 4.2. This is similar to the manner in which the “THXfeature pluginFeature Plugin A plugin that was created with the intention of eventually being proposed for inclusion in WordPress Core. See Features as Plugins. team re-did themes in 3.8 and theme-install in 3.9.

#4-2, #customize, #feature-plugins, #merge, #proposal, #theme-switcher, #themes