Theme development

ContentBox Theme Development (BoxLang)

Build custom themes for ContentBox CMS using BoxLang. Themes control the visual presentation of all public-facing content — blog entries, pages, archives, search results, and error pages.

Theme Structure

A ContentBox theme is a directory under modules_app/contentbox-custom/_themes/ (custom) or modules/contentbox/themes/ (core) containing:

MyTheme/
├── Theme.bx               ← Theme metadata, settings, lifecycle callbacks
├── screenshot.png         ← Theme preview image (shown in admin)
├── layouts/
│   ├── blog.bx            ← MANDATORY: Blog entry layout
│   └── pages.bx           ← MANDATORY: Page layout
│   ├── maintenance.bx     ← Optional: Maintenance mode layout
│   └── search.bx          ← Optional: Search results layout (defaults to pages)
├── views/
│   ├── index.bx           ← MANDATORY: Home page (blog entry listing)
│   ├── entry.bx           ← MANDATORY: Single blog entry with comments
│   ├── page.bx            ← MANDATORY: Single page rendering
│   ├── archives.bx        ← MANDATORY: Blog archives view
│   ├── error.bx           ← MANDATORY: Error display
│   ├── notfound.bx        ← Optional: Entry not found view
│   └── maintenance.bx     ← Optional: Maintenance mode view
├── templates/
│   ├── entry.bx           ← Collection template for entry iterations
│   ├── category.bx        ← Collection template for category iterations
│   └── comment.bx         ← Collection template for comment iterations
├── widgets/               ← Theme-specific widget overrides
│   └── MyWidget.bx        ← Overrides core widgets of the same name
└── includes/              ← Help files, assets, etc.

Theme.bx

The Theme.bx defines metadata, settings, and lifecycle callbacks:

// Theme Metadata
this.name          = "My Custom Theme";
this.description   = "A beautiful custom theme for ContentBox";
this.version       = "1.0.0";
this.author        = "Your Name";
this.authorURL     = "https://example.com";
this.screenShotURL = "screenshot.png";

// Theme Settings — array of setting structs
this.settings = [
	{
		name         : "siteTitle",
		defaultValue : "My Site",
		type         : "text",
		label        : "Site Title:",
		required     : true,
		group        : "General"
	},
	{
		name         : "primaryColor",
		defaultValue : "#3b82f6",
		type         : "color",
		label        : "Primary Color:",
		group        : "Colors"
	},
	{
		name         : "showSidebar",
		defaultValue : true,
		type         : "boolean",
		label        : "Show Sidebar:",
		group        : "Layout"
	},
	{
		name         : "layoutStyle",
		defaultValue : "grid",
		type         : "select",
		label        : "Entry Layout:",
		options      : "grid,list,masonry",
		group        : "Layout"
	},
	{
		name         : "footerText",
		defaultValue : "",
		type         : "textarea",
		label        : "Footer Text:",
		group        : "General"
	}
];

/**
 * Called when the theme is activated
 */
function onActivation(){
	// Run setup logic, create default content, etc.
}

/**
 * Called when the theme is deactivated
 */
function onDeactivation(){
	// Cleanup logic
}

/**
 * Called when the theme is deleted
 */
function onDelete(){
	// Cleanup logic
}

Setting Types

Type	Description
text	Single-line text input (default)
textarea	Multi-line text area
boolean	Checkbox toggle
select	Dropdown select box
color	Color picker

Setting Struct Keys

Key	Required	Description
name	Yes	Setting name (saved as cb_themeName_settingName)
defaultValue	Yes	Default value
type	No	HTML control type (default: text)
label	No	HTML label (defaults to name)
required	No	Whether the setting is required (default: false)
title	No	HTML title attribute
options	No	For select: comma-separated list or array of values, or array of {name, value} structs
optionsUDF	No	UDF name (no parentheses) that returns options, e.g., getColors
group	No	Group name for organizing settings
groupIntro	No	Description text for a group
fieldDescription	No	Description for an individual field
fieldHelp	No	HTML for a modal help popup (use loadHelpFile() helper)

Accessing Theme Settings in Views

Theme settings are available via the cb helper:

// Get a theme setting
cb.getThemeSetting( "siteTitle" )
cb.getThemeSetting( "primaryColor" )

// With fallback default
cb.getThemeSetting( "showSidebar", true )

Layout Files

blog.bx — Blog Entry Layout

<!DOCTYPE html>
<html lang="en">
<head>
	<meta charset="UTF-8">
	<meta name="viewport" content="width=device-width, initial-scale=1.0">
	<title>#{cb.getContent().getTitle()}# — #{cb.getThemeSetting( "siteTitle" )}#</title>
	#{renderView( view = "_assets/head" )}#
</head>
<body>
	#{renderView( view = "_assets/header" )}#

	<main class="container">
		#{renderView()}#
	</main>

	#{renderView( view = "_assets/footer" )}#
</body>
</html>

pages.bx — Page Layout

Similar structure to blog.bx, used for rendering static pages.

View Files

index.bx — Home Page

// Render entries using collection template
cb.renderCollection(
	template   : "entry",
	collection : prc.entries,
	counter    : prc.start,
	totalItems : prc.totalRecords
)

// Pagination
cb.paginator(
	totalRecords : prc.totalRecords,
	maxRows      : prc.maxRows,
	page         : prc.page,
	pageLink     : cb.siteURL() & "/page/{page}",
	align        : "center"
)

entry.bx — Single Blog Entry

entry = cb.getContent()

<article class="entry">
	<header>
		<h1>#{entry.getTitle()}#</h1>
		<div class="meta">
			By #{entry.getAuthor().getFullName()}#
			on #{dateFormat( entry.getCreatedDate(), "mmmm d, yyyy" )}#
		</div>
	</header>

	<div class="content">
		#{entry.getHTMLContent()}#
	</div>

	// Categories
	if( entry.getCategories().recordCount ){
		writeOutput( '
			<div class="categories">
				#{cb.renderCollection(
					template   : "category",
					collection : entry.getCategories()
				)}#
			</div>
		' )
	}

	// Comments
	cb.widget( "CommentForm" )
</article>

page.bx — Single Page

page = cb.getContent()

<article class="page">
	<h1>#{page.getTitle()}#</h1>
	<div class="content">
		#{page.getHTMLContent()}#
	</div>
</article>

archives.bx — Archives View

<h1>Archives</h1>

// Monthly archives
<div class="archives-by-month">
	#{cb.renderCollection(
		template   : "entry",
		collection : prc.entries
	)}#
</div>

// Pagination
#{cb.paginator(
	totalRecords : prc.totalRecords,
	maxRows      : prc.maxRows,
	page         : prc.page
)}#

error.bx — Error Display

<div class="error-page">
	<h1>Error</h1>
	<p>#{prc.errorMessage ?: "An unexpected error occurred."}#</p>
	<a href="#{cb.siteURL()}#" class="btn">Return Home</a>
</div>

Collection Templates

Templates in templates/ are used with cb.renderCollection(). Each template receives:

• _counter — Current iteration index (1-based)
• _items — Total number of items in the collection
• {templateName} — The object being rendered (e.g., entry, category, comment)

templates/entry.bx

<article class="entry-preview">
	<h2>
		<a href="#{cb.entryURL( entry )}#">#{entry.getTitle()}#</a>
	</h2>
	<div class="meta">
		#{dateFormat( entry.getCreatedDate(), "mmmm d, yyyy" )}#
		by #{entry.getAuthor().getFullName()}#
	</div>
	<div class="excerpt">
		#{entry.getHTMLContentExcerpt()}#
	</div>
</article>

templates/category.bx

<a href="#{cb.categoryURL( category )}#" class="category-tag">
	#{category.getCategory()}#
</a>

templates/comment.bx

<div class="comment">
	<div class="comment-author">#{comment.getAuthor()}#</div>
	<div class="comment-date">#{dateFormat( comment.getCreatedDate(), "mmmm d, yyyy" )}#</div>
	<div class="comment-body">#{comment.getComment()}#</div>
</div>

Widget Overrides

Place widgets in widgets/ to override core widgets of the same name:

// widgets/Menu.bx — overrides the core Menu widget
component extends="contentbox.models.ui.BaseWidget" singleton {

	function init(){
		setName( "Menu" )
		setVersion( "1.0.0" )
		setDescription( "Custom menu widget override" )
	}

	any function renderIt( string menuName = "main" ){
		// Custom menu rendering
	}

}

The CB Helper

The cb helper (CBHelper@contentbox) is the primary API for theme development:

// Site info
cb.site()                    // Current site entity
cb.siteURL()                 // Site base URL
cb.siteName()                // Site name

// Content
cb.getContent()              // Current content (entry/page)
cb.entryURL( entry )         // Entry permalink
cb.pageURL( page )           // Page URL
cb.categoryURL( category )   // Category URL

// Theme settings
cb.getThemeSetting( "name" )

// Widgets
cb.widget( "WidgetName", { arg1 : "value" } )

// Rendering
cb.renderCollection( template : "entry", collection : query )
cb.renderView( view = "partial" )

// Menus
cb.menu( "main" )

// RSS feeds
cb.rssURL()
cb.rssCommentsURL()

// Search
cb.searchURL()
cb.searchURL( "query" )

// Subscriptions
cb.subscribeURL()
cb.unsubscribeURL()

Theme Discovery and Registration

ContentBox discovers themes from two locations:

1. Core themes: modules/contentbox/themes/
2. Custom themes: modules_app/contentbox-custom/_themes/

The ThemeService@contentbox builds the theme registry at startup. Custom themes override core themes of the same name.

Theme Switching

Themes can be switched per-site via admin settings. The active theme is resolved at runtime:

// In a handler or service
property name="themeService" inject="themeService@contentbox"

activeTheme = themeService.getActiveTheme()
themePath   = themeService.getThemePath( activeTheme )

Best Practices

1. Always include mandatory files: Theme.bx, blog.bx, pages.bx, index.bx, entry.bx, page.bx, archives.bx, error.bx
2. Use cb helper for all URL generation — never hardcode paths
3. Use collection templates for iterating over entries, categories, comments
4. Group theme settings logically using the group key
5. Provide screenshot.png for admin theme preview
6. Use loadHelpFile() for field help that reads from includes/help/
7. Keep theme-specific widgets in the theme's widgets/ folder
8. Test with multiple content types — entries, pages, categories, search results
9. Use prc scope for handler-passed data in views
10. Leverage BoxLang features — null coalescing (?:), Elvis operator, modern syntax

Engine Compatibility

This skill targets BoxLang engine. For CFML-specific syntax (Lucee 5+, Adobe ColdFusion 2018+), see the CFML variant of this skill.

Key BoxLang advantages:

• Use #{...}# for inline expression output in .bx templates
• No <cfoutput> wrapper needed
• Modern syntax: ?: null coalescing, ?. safe navigation
• Cleaner function calls without parentheses when no arguments
• Native support for modern data structures