Hyvä CMS Custom Field Type Creator

Overview

This skill guides the creation of custom field types and field handlers for Hyvä CMS components. Custom field types extend the built-in field types (text, textarea, select, etc.) with specialized input controls for the CMS editor interface.

Two types of custom fields:

1. Basic Custom Field Type: Custom input control with direct data entry (e.g., date range, color picker, custom validation)
2. Field Handler: Enhanced UI with complex interactions (e.g., product selector with images, searchable dropdown, link configuration modal)

Command execution: For commands that need to run inside the development environment (e.g., bin/magento), use the hyva-exec-shell-cmd skill to detect the environment and determine the appropriate command wrapper.

Workflow

Step 1: Module Selection

If not already specified in the prompt, determine where to create the custom field type:

Option A: New Module

Use the hyva-create-module skill with:

• dependencies: ["Hyva_CmsBase", "Hyva_CmsLiveviewEditor"]
• composer_require: {"hyva-themes/commerce-module-cms": "^1.0"}

Option B: Existing Module

Verify the module has required dependencies:

• Hyva_CmsBase and Hyva_CmsLiveviewEditor in etc/module.xml
• hyva-themes/commerce-module-cms in composer.json

Add missing dependencies if needed.

Step 2: Field Type Details

Gather information about the custom field type:

1. Field type name (lowercase identifier, e.g., date_range, product_selector, color_picker)
2. Purpose (what data does it collect?)
3. UI pattern:
   • Basic field: Simple input with validation (date picker, pattern input, enhanced text field)
   • Inline handler: Enhanced control in field area (searchable dropdown, color picker)
   • Modal handler: Separate dialog for complex selection (product selector, link builder, media gallery)
4. Data structure (simple string, JSON object, array?)
5. Validation requirements (pattern, required, custom rules?)

Step 3: Implementation Pattern Selection

Based on the UI pattern identified in Step 2:

Pattern A: Basic Custom Field Type

For simple inputs with custom HTML5 validation or specialized input controls:

• Single template file for the field
• No separate handler modal
• Example: Date range selector, custom pattern validation, slider input

Pattern B: Inline Field Handler

For enhanced controls that remain in the field area:

• Single template file with Alpine.js component
• No separate handler modal
• Example: Searchable select dropdown, color picker with swatches

Pattern C: Modal-Based Field Handler

For complex selection interfaces requiring more space:

• Field template (displays selection + trigger button)
• Handler modal template (separate dialog with full UI)
• Layout XML registration for the handler
• Example: Product selector, link configuration, media gallery

See references/handler-patterns.md for detailed implementation patterns and code examples for each type.

Step 4: Generate Field Template

Create the field template at view/adminhtml/templates/field-types/[field-type-name].phtml.

Required template elements:

1. Field container with proper ID: field-container-{uid}_{fieldName}
2. Input element(s) with name: {uid}_{fieldName}
3. Validation messages container: validation-messages-{uid}_{fieldName}
4. updateWireField() or updateField() call on value change
5. Error state handling via $magewire->errors
6. IMPORTANT: Use null coalescing for field value: $block->getData('value') ?? '' (NOT type casting)

Use the appropriate template from assets/templates/:

• basic-field.phtml.tpl - Basic custom field type
• inline-handler.phtml.tpl - Inline enhanced control
• modal-field.phtml.tpl - Modal handler field template

See references/template-requirements.md for detailed template requirements and patterns.

Step 5: Generate Handler Modal (if needed)

For modal-based handlers only, create the handler template at view/adminhtml/templates/handlers/[handler-name]-handler.phtml.

Handler modal structure:

1. <dialog> element with Alpine.js component and open:flex class (NOT static flex)
2. Listen for initialization event from field template
3. Implement selection UI (search, filters, grid, etc.)
4. Dispatch editor-change event on save

Use assets/templates/modal-handler.phtml.tpl as the starting point.

See references/handler-communication.md for event protocols and data exchange patterns.

Step 6: Register Field Type

Add registration to etc/adminhtml/di.xml:

<type name="Hyva\CmsLiveviewEditor\Model\CustomField">
    <arguments>
        <argument name="customTypes" xsi:type="array">
            <item name="[field_type_name]" xsi:type="string">
                [Vendor]_[Module]::field-types/[field-type-name].phtml
            </item>
        </argument>
    </arguments>
</type>

Step 7: Register Handler Modal (if needed)

For modal-based handlers only, create or update view/adminhtml/layout/liveview_editor.xml:

<?xml version="1.0"?>
<page xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
      xsi:noNamespaceSchemaLocation="urn:magento:framework:View/Layout/etc/page_configuration.xsd">
    <body>
        <referenceContainer name="before.body.end">
            <block name="[handler_name]_handler"
                   template="[Vendor]_[Module]::handlers/[handler-name]-handler.phtml"/>
        </referenceContainer>
    </body>
</page>

Note: Inline handlers do NOT require layout XML registration.

Step 8: Usage Example

Provide an example of using the custom field type in components.json:

{
    "my_component": {
        "label": "My Component",
        "content": {
            "[field_name]": {
                "type": "custom_type",
                "custom_type": "[field_type_name]",
                "label": "Field Label",
                "attributes": {
                    "required": true,
                    "pattern": ".*"
                }
            }
        }
    }
}

Resources

references/template-requirements.md

Complete reference for custom field type template requirements:

• Required markup patterns and element IDs
• Field container structure
• Validation message containers
• Field value update methods (updateWireField vs updateField)
• HTML5 validation attributes
• Error state handling

Read this file when implementing the field template to ensure proper integration with the CMS editor.

references/handler-patterns.md

Implementation patterns for all three custom field types:

• Basic custom field type (simple input)
• Inline field handler (enhanced control)
• Modal-based field handler (dialog selection)

Each pattern includes:

• Complete code examples
• When to use each pattern
• Alpine.js component structure
• Data flow and state management

Read this file when selecting the implementation pattern and writing the template code.

references/handler-communication.md

Event protocols and data exchange for field handlers:

• Initialization event structure
• Save event structure
• Field value encoding/decoding
• Error handling patterns
• Common pitfalls and solutions

Read this file when implementing handler modals to understand the communication protocol.

references/built-in-handlers.md

Reference for Hyvä CMS built-in field handlers:

• Product Handler (modal-based, image grid selection)
• Link Handler (modal-based, multi-type link config)
• Searchable Select (inline enhanced dropdown)

Each includes:

• Location in Hyvä CMS module
• Key features and patterns
• Usage examples
• Code to examine for patterns

Read this file when looking for implementation examples or patterns to copy.

assets/templates/basic-field.phtml.tpl

Template for basic custom field types with custom validation or input controls.

Placeholders:

• {{FIELD_TYPE_NAME}} - Custom field type identifier
• {{FIELD_INPUTS}} - Input element(s) HTML
• {{VALIDATION_LOGIC}} - Custom validation JavaScript (optional)

assets/templates/inline-handler.phtml.tpl

Template for inline enhanced controls (searchable dropdown, color picker, etc.).

Placeholders:

• {{HANDLER_NAME}} - Alpine.js component name
• {{HANDLER_LOGIC}} - Alpine.js component implementation
• {{HANDLER_UI}} - Enhanced control HTML

assets/templates/modal-field.phtml.tpl

Field template for modal-based handlers (trigger button + hidden input).

Placeholders:

• {{EVENT_NAME}} - Custom event name to dispatch
• {{BUTTON_LABEL}} - Button text
• {{DISPLAY_VALUE}} - Current selection display

assets/templates/modal-handler.phtml.tpl

Handler modal template for modal-based selection interfaces.

Placeholders:

• {{HANDLER_NAME}} - Alpine.js component name
• {{MODAL_TITLE}} - Dialog header text
• {{SELECTION_UI}} - Selection interface HTML
• {{SAVE_LOGIC}} - Save button logic

Important Guidelines

Core Requirements

1. Template Requirements: All custom field types must follow required markup patterns (container ID, input name, validation messages)
2. Handler Registration: Modal handlers need layout XML registration; inline handlers do not
3. Validation: Apply HTML5 validation attributes via $filteredAttributes for automatic validation
4. Alpine Components: If using custom Alpine components, keep input fields outside the component and update via vanilla JS
5. Built-In Examples: Reference built-in handlers in Hyva_CmsLiveviewEditor::page/js/ for proven patterns

Accurate Patterns from Codebase

Based on built-in Hyvä CMS handler implementations:

1. Event Naming Convention: Use toggle-{type}-select pattern

   • ✅ Correct: toggle-product-select, toggle-link-select, toggle-category-select
   • ❌ Incorrect: toggle-product-handler, toggle-link-handler

2. Handler Function Naming: Use init{Type}Select() pattern

   • ✅ Examples: initProductSelect(), initLinkSelect(), initCategorySelect()

3. Field Value Update Methods:

   • Use updateWireField (default): Products, Link, Category handlers
     • Triggers immediate server-side validation via Magewire
     • Keeps component state synchronized
   • Use updateField (specialized): Image handler, debounced inputs (color, range)
     • Updates preview without server round-trip
     • Defers validation until save

4. JSON Encoding Pattern: All complex data (arrays, objects) must be JSON-encoded

   // Field template
   value="<?= $escaper->escapeHtmlAttr(json_encode($fieldValue)) ?>"
   
   // Handler initialization
   const data = JSON.parse(fieldValue);
   
   // @change handler
   @change="updateWireField(..., JSON.parse($event.target.value))"
   

5. wire:ignore for Livewire Compatibility: Searchable select uses wire:ignore wrapper

   <div wire:ignore>
       <div x-data="initSearchableSelect(...)">
           <!-- Alpine component -->
       </div>
   </div>
   

6. Separate Handler Files: Even inline handlers may have separate function files

   • Field template: liveview/field-types/searchable_select.phtml
   • Handler function: page/js/searchable-select-handler.phtml

7. Icons View Model: Use for UI elements

   /** @var Icons $icons */
   $icons = $viewModels->require(Icons::class);
   <?= /** @noEscape */ $icons->trashHtml('', 22, 22) ?>
   

8. FieldTypes View Model: Use for attribute filtering

   /** @var FieldTypes $fieldTypes */
   $fieldTypes = $viewModels->require(FieldTypes::class);
   $filteredAttributes = $fieldTypes->getDefinedFieldAttributes($attributes);
   // Or for specific attributes:
   $filteredAttributes = $fieldTypes->getAttributesByKeys($attributes, ['required', 'data-required']);
   

9. CRITICAL: Layout XML referenceContainer: Handler modals MUST use before.body.end container

   • ✅ Correct: <referenceContainer name="before.body.end">
   • ❌ Incorrect: <referenceContainer name="content">
   • The before.body.end container ensures the handler modal is loaded at the end of the page body, which is required for proper Alpine.js initialization and modal functionality

10. CRITICAL: Field Value Type Handling: NEVER use type casting for field values, always use null coalescing operator

• ✅ Correct: $fieldValue = $block->getData('value') ?? '';
• ❌ Incorrect: $fieldValue = (string) $block->getData('value');
• Type casting (string) will fail when value is null, causing PHP errors
• Use ?? '' for string values, ?? [] for array values, or appropriate default for your data type
• Reference: See built-in field types like category.phtml which use ?? [] pattern

11. CRITICAL: Dialog Modal Classes: Handler modals must use open:flex not static flex class

• ✅ Correct: <dialog class="... open:flex flex-col">
• ❌ Incorrect: <dialog class="... flex flex-col"> (modal always visible)
• The open: prefix applies styles only when dialog is open (native HTML dialog state)
• Reference: See built-in handlers like category-handler.phtml which use open:flex flex-col

12. CRITICAL: Complex Data Type Handling: For fields storing JSON/array data, handle BOTH array and string types

• Field values may be returned as already-decoded arrays OR as JSON strings (depends on storage/context)
• ✅ Correct pattern:

  $data = ['default' => 'structure'];
  if ($fieldValue) {
      if (is_array($fieldValue)) {
          $data = $fieldValue;  // Already decoded
      } elseif (is_string($fieldValue)) {
          $decoded = json_decode($fieldValue, true);
          if (is_array($decoded)) {
              $data = $decoded;
          }
      }
  }
  
  // When outputting to hidden input, ALWAYS ensure it's a JSON string
  $fieldValueJson = is_array($fieldValue) ? json_encode($fieldValue) : $fieldValue;
  

• ❌ Incorrect: json_decode($fieldValue) without type checking (fails if value is already an array)
• ❌ Incorrect: Using array directly in value attribute without JSON-encoding first