lion/packages/form-core/src/FormControlMixin.js

949 lines
32 KiB
JavaScript

import { css, dedupeMixin, html, nothing, SlotMixin, DisabledMixin } from '@lion/core';
import { getAriaElementsInRightDomOrder } from './utils/getAriaElementsInRightDomOrder.js';
import { Unparseable } from './validate/Unparseable.js';
import { FormRegisteringMixin } from './registration/FormRegisteringMixin.js';
/**
* @typedef {import('@lion/core').TemplateResult} TemplateResult
* @typedef {import('@lion/core').CSSResult} CSSResult
* @typedef {import('@lion/core').CSSResultArray} CSSResultArray
* @typedef {import('@lion/core').nothing} nothing
* @typedef {import('@lion/core/types/SlotMixinTypes').SlotsMap} SlotsMap
* @typedef {import('./validate/LionValidationFeedback').LionValidationFeedback} LionValidationFeedback
* @typedef {import('../types/choice-group/ChoiceInputMixinTypes').ChoiceInputHost} ChoiceInputHost
* @typedef {import('../types/FormControlMixinTypes.js').FormControlHost} FormControlHost
* @typedef {import('../types/FormControlMixinTypes.js').HTMLElementWithValue} HTMLElementWithValue
* @typedef {import('../types/FormControlMixinTypes.js').FormControlMixin} FormControlMixin
* @typedef {import('../types/FormControlMixinTypes.js').ModelValueEventDetails} ModelValueEventDetails
*/
/**
* Generates random unique identifier (for dom elements)
* @param {string} prefix
*/
function uuid(prefix) {
return `${prefix}-${Math.random().toString(36).substr(2, 10)}`;
}
/**
* #FormControlMixin :
*
* This Mixin is a shared fundament for all form components, it's applied on:
* - LionField (which is extended to LionInput, LionTextarea, LionSelect etc. etc.)
* - LionFieldset (which is extended to LionRadioGroup, LionCheckboxGroup, LionForm)
* @param {import('@open-wc/dedupe-mixin').Constructor<import('@lion/core').LitElement>} superclass
* @type {FormControlMixin}
*/
const FormControlMixinImplementation = superclass =>
// eslint-disable-next-line no-shadow, no-unused-vars
class FormControlMixin extends FormRegisteringMixin(DisabledMixin(SlotMixin(superclass))) {
/** @type {any} */
static get properties() {
return {
name: { type: String, reflect: true },
readOnly: { type: Boolean, attribute: 'readonly', reflect: true },
label: String, // FIXME: { attribute: false } breaks a bunch of tests, but shouldn't...
helpText: { type: String, attribute: 'help-text' },
modelValue: { attribute: false },
_ariaLabelledNodes: { attribute: false },
_ariaDescribedNodes: { attribute: false },
_repropagationRole: { attribute: false },
_isRepropagationEndpoint: { attribute: false },
};
}
/**
* The label text for the input node.
* When no light dom defined via [slot=label], this value will be used.
* @type {string}
*/
get label() {
return this.__label || (this._labelNode && this._labelNode.textContent) || '';
}
/**
* @param {string} newValue
*/
set label(newValue) {
const oldValue = this.label;
/** @type {string} */
this.__label = newValue;
this.requestUpdate('label', oldValue);
}
/**
* The helpt text for the input node.
* When no light dom defined via [slot=help-text], this value will be used
* @type {string}
*/
get helpText() {
return this.__helpText || (this._helpTextNode && this._helpTextNode.textContent) || '';
}
/**
* @param {string} newValue
*/
set helpText(newValue) {
const oldValue = this.helpText;
/** @type {string} */
this.__helpText = newValue;
this.requestUpdate('helpText', oldValue);
}
/**
* Will be used in validation messages to refer to the current field
* @type {string}
*/
get fieldName() {
return this.__fieldName || this.label || this.name || '';
}
/**
* @param {string} value
*/
set fieldName(value) {
/** @type {string} */
this.__fieldName = value;
}
/**
* @configure SlotMixin
*/
get slots() {
return {
...super.slots,
label: () => {
const label = document.createElement('label');
label.textContent = this.label;
return label;
},
'help-text': () => {
const helpText = document.createElement('div');
helpText.textContent = this.helpText;
return helpText;
},
};
}
/**
* The interactive (form) element. Can be a native element like input/textarea/select or
* an element with tabindex > -1
* @protected
*/
get _inputNode() {
return /** @type {HTMLElementWithValue} */ (this.__getDirectSlotChild('input'));
}
/**
* Element where label will be rendered to
* @protected
*/
get _labelNode() {
return /** @type {HTMLElement} */ (this.__getDirectSlotChild('label'));
}
/**
* Element where help text will be rendered to
* @protected
*/
get _helpTextNode() {
return /** @type {HTMLElement} */ (this.__getDirectSlotChild('help-text'));
}
/**
* Element where validation feedback will be rendered to
* @protected
*/
get _feedbackNode() {
return /** @type {LionValidationFeedback} */ (this.__getDirectSlotChild('feedback'));
}
constructor() {
super();
/**
* The name the element will be registered with to the .formElements collection
* of the parent. Also, it serves as the key of key/value pairs in
* modelValue/serializedValue objects
* @type {string}
*/
this.name = '';
/**
* A Boolean attribute which, if present, indicates that the user should not be able to edit
* the value of the input. The difference between disabled and readonly is that read-only
* controls can still function, whereas disabled controls generally do not function as
* controls until they are enabled.
* (From: https://developer.mozilla.org/en-US/docs/Web/HTML/Element/input#attr-readonly)
* @type {boolean}
*/
this.readOnly = false;
/**
* The label text for the input node.
* When no value is defined, textContent of [slot=label] will be used
* @type {string}
*/
this.label = '';
/**
* The helpt text for the input node.
* When no value is defined, textContent of [slot=help-text] will be used
* @type {string}
*/
this.helpText = '';
/**
* The model value is the result of the parser function(when available).
* It should be considered as the internal value used for validation and reasoning/logic.
* The model value is 'ready for consumption' by the outside world (think of a Date
* object or a float). The modelValue can(and is recommended to) be used as both input
* value and output value of the `LionField`.
*
* Examples:
* - For a date input: a String '20/01/1999' will be converted to new Date('1999/01/20')
* - For a number input: a formatted String '1.234,56' will be converted to a Number:
* 1234.56
*/
// TODO: we can probably set this up properly once propert effects run from firstUpdated
// this.modelValue = undefined;
/**
* Unique id that can be used in all light dom
* @type {string}
* @protected
*/
this._inputId = uuid(this.localName);
/**
* Contains all elements that should end up in aria-labelledby of `._inputNode`
* @type {HTMLElement[]}
*/
this._ariaLabelledNodes = [];
/**
* Contains all elements that should end up in aria-describedby of `._inputNode`
* @type {HTMLElement[]}
*/
this._ariaDescribedNodes = [];
/**
* Based on the role, details of handling model-value-changed repropagation differ.
* @type {'child'|'choice-group'|'fieldset'}
*/
this._repropagationRole = 'child';
/**
* By default, a field with _repropagationRole 'choice-group' will act as an
* 'endpoint'. This means it will be considered as an individual field: for
* a select, individual options will not be part of the formPath. They
* will.
* Similarly, components that (a11y wise) need to be fieldsets, but 'interaction wise'
* (from Application Developer perspective) need to be more like fields
* (think of an amount-input with a currency select box next to it), can set this
* to true to hide private internals in the formPath.
* @type {boolean}
*/
this._isRepropagationEndpoint = false;
this.addEventListener(
'model-value-changed',
/** @type {EventListenerOrEventListenerObject} */ (this.__repropagateChildrenValues),
);
/** @type {EventListener} */
this._onLabelClick = this._onLabelClick.bind(this);
}
connectedCallback() {
super.connectedCallback();
this._enhanceLightDomClasses();
this._enhanceLightDomA11y();
this._triggerInitialModelValueChangedEvent();
if (this._labelNode) {
this._labelNode.addEventListener('click', this._onLabelClick);
}
}
disconnectedCallback() {
super.disconnectedCallback();
if (this._labelNode) {
this._labelNode.removeEventListener('click', this._onLabelClick);
}
}
/** @param {import('@lion/core').PropertyValues } changedProperties */
updated(changedProperties) {
super.updated(changedProperties);
if (changedProperties.has('_ariaLabelledNodes')) {
this.__reflectAriaAttr(
'aria-labelledby',
this._ariaLabelledNodes,
this.__reorderAriaLabelledNodes,
);
}
if (changedProperties.has('_ariaDescribedNodes')) {
this.__reflectAriaAttr(
'aria-describedby',
this._ariaDescribedNodes,
this.__reorderAriaDescribedNodes,
);
}
if (changedProperties.has('label') && this._labelNode) {
this._labelNode.textContent = this.label;
}
if (changedProperties.has('helpText') && this._helpTextNode) {
this._helpTextNode.textContent = this.helpText;
}
if (changedProperties.has('name')) {
this.dispatchEvent(
/** @privateEvent */
new CustomEvent('form-element-name-changed', {
detail: { oldName: changedProperties.get('name'), newName: this.name },
bubbles: true,
}),
);
}
}
/** @protected */
_triggerInitialModelValueChangedEvent() {
this._dispatchInitialModelValueChangedEvent();
}
/** @protected */
_enhanceLightDomClasses() {
if (this._inputNode) {
this._inputNode.classList.add('form-control');
}
}
/** @protected */
_enhanceLightDomA11y() {
const { _inputNode, _labelNode, _helpTextNode, _feedbackNode } = this;
if (_inputNode) {
_inputNode.id = _inputNode.id || this._inputId;
}
if (_labelNode) {
_labelNode.setAttribute('for', this._inputId);
this.addToAriaLabelledBy(_labelNode, { idPrefix: 'label' });
}
if (_helpTextNode) {
this.addToAriaDescribedBy(_helpTextNode, { idPrefix: 'help-text' });
}
if (_feedbackNode) {
// Generic focus/blur handling that works for both Fields/FormGroups
this.addEventListener('focusin', () => {
_feedbackNode.setAttribute('aria-live', 'polite');
});
this.addEventListener('focusout', () => {
_feedbackNode.setAttribute('aria-live', 'assertive');
});
this.addToAriaDescribedBy(_feedbackNode, { idPrefix: 'feedback' });
}
this._enhanceLightDomA11yForAdditionalSlots();
}
/**
* Enhances additional slots(prefix, suffix, before, after) defined by developer.
*
* When boolean attribute data-label or data-description is found,
* the slot element will be connected to the input via aria-labelledby or aria-describedby
* @param {string[]} additionalSlots
* @protected
*/
_enhanceLightDomA11yForAdditionalSlots(
additionalSlots = ['prefix', 'suffix', 'before', 'after'],
) {
additionalSlots.forEach(additionalSlot => {
const element = this.__getDirectSlotChild(additionalSlot);
if (element) {
if (element.hasAttribute('data-label')) {
this.addToAriaLabelledBy(element, { idPrefix: additionalSlot });
}
if (element.hasAttribute('data-description')) {
this.addToAriaDescribedBy(element, { idPrefix: additionalSlot });
}
}
});
}
/**
* Will handle help text, validation feedback and character counter,
* prefix/suffix/before/after (if they contain data-description flag attr).
* Also, contents of id references that will be put in the <lion-field>._ariaDescribedby property
* from an external context, will be read by a screen reader.
* @param {string} attrName
* @param {HTMLElement[]} nodes
* @param {boolean|undefined} reorder
*/
__reflectAriaAttr(attrName, nodes, reorder) {
if (this._inputNode) {
if (reorder) {
const insideNodes = nodes.filter(n => this.contains(n));
const outsideNodes = nodes.filter(n => !this.contains(n));
// eslint-disable-next-line no-param-reassign
nodes = [...getAriaElementsInRightDomOrder(insideNodes), ...outsideNodes];
}
const string = nodes.map(n => n.id).join(' ');
this._inputNode.setAttribute(attrName, string);
}
}
/**
* Default Render Result:
* <div class="form-field__group-one">
* <div class="form-field__label">
* <slot name="label"></slot>
* </div>
* <small class="form-field__help-text">
* <slot name="help-text"></slot>
* </small>
* </div>
* <div class="form-field__group-two">
* <div class="input-group">
* <div class="input-group__before">
* <slot name="before"></slot>
* </div>
* <div class="input-group__container">
* <div class="input-group__prefix">
* <slot name="prefix"></slot>
* </div>
* <div class="input-group__input">
* <slot name="input"></slot>
* </div>
* <div class="input-group__suffix">
* <slot name="suffix"></slot>
* </div>
* </div>
* <div class="input-group__after">
* <slot name="after"></slot>
* </div>
* </div>
* <div class="form-field__feedback">
* <slot name="feedback"></slot>
* </div>
* </div>
*/
render() {
return html`
<div class="form-field__group-one">${this._groupOneTemplate()}</div>
<div class="form-field__group-two">${this._groupTwoTemplate()}</div>
`;
}
/**
* @return {TemplateResult}
* @protected
*/
_groupOneTemplate() {
return html` ${this._labelTemplate()} ${this._helpTextTemplate()} `;
}
/**
* @return {TemplateResult}
* @protected
*/
_groupTwoTemplate() {
return html` ${this._inputGroupTemplate()} ${this._feedbackTemplate()} `;
}
/**
* @return {TemplateResult}
* @protected
*/
// eslint-disable-next-line class-methods-use-this
_labelTemplate() {
return html`
<div class="form-field__label">
<slot name="label"></slot>
</div>
`;
}
/**
* @return {TemplateResult}
* @protected
*/
// eslint-disable-next-line class-methods-use-this
_helpTextTemplate() {
return html`
<small class="form-field__help-text">
<slot name="help-text"></slot>
</small>
`;
}
/**
* @return {TemplateResult}
* @protected
*/
_inputGroupTemplate() {
return html`
<div class="input-group">
${this._inputGroupBeforeTemplate()}
<div class="input-group__container">
${this._inputGroupPrefixTemplate()} ${this._inputGroupInputTemplate()}
${this._inputGroupSuffixTemplate()}
</div>
${this._inputGroupAfterTemplate()}
</div>
`;
}
/**
* @return {TemplateResult}
* @protected
*/
// eslint-disable-next-line class-methods-use-this
_inputGroupBeforeTemplate() {
return html`
<div class="input-group__before">
<slot name="before"></slot>
</div>
`;
}
/**
* @return {TemplateResult | nothing}
* @protected
*/
_inputGroupPrefixTemplate() {
return !Array.from(this.children).find(child => child.slot === 'prefix')
? nothing
: html`
<div class="input-group__prefix">
<slot name="prefix"></slot>
</div>
`;
}
/**
* @return {TemplateResult}
* @protected
*/
// eslint-disable-next-line class-methods-use-this
_inputGroupInputTemplate() {
return html`
<div class="input-group__input">
<slot name="input"></slot>
</div>
`;
}
/**
* @return {TemplateResult | nothing}
* @protected
*/
_inputGroupSuffixTemplate() {
return !Array.from(this.children).find(child => child.slot === 'suffix')
? nothing
: html`
<div class="input-group__suffix">
<slot name="suffix"></slot>
</div>
`;
}
/**
* @return {TemplateResult}
* @protected
*/
// eslint-disable-next-line class-methods-use-this
_inputGroupAfterTemplate() {
return html`
<div class="input-group__after">
<slot name="after"></slot>
</div>
`;
}
/**
* @return {TemplateResult}
* @protected
*/
// eslint-disable-next-line class-methods-use-this
_feedbackTemplate() {
return html`
<div class="form-field__feedback">
<slot name="feedback"></slot>
</div>
`;
}
/**
* Used for Required validation and computation of interaction states
* @param {any} modelValue
* @return {boolean}
* @protected
*/
_isEmpty(modelValue = /** @type {any} */ (this).modelValue) {
let value = modelValue;
if (/** @type {any} */ (this).modelValue instanceof Unparseable) {
value = /** @type {any} */ (this).modelValue.viewValue;
}
// Checks for empty platform types: Objects, Arrays, Dates
if (typeof value === 'object' && value !== null && !(value instanceof Date)) {
return !Object.keys(value).length;
}
// eslint-disable-next-line no-mixed-operators
// Checks for empty platform types: Numbers, Booleans
const isNumberValue = typeof value === 'number' && (value === 0 || Number.isNaN(value));
const isBooleanValue = typeof value === 'boolean' && value === false;
return !value && !isNumberValue && !isBooleanValue;
}
/**
* All CSS below is written from a generic mindset, following BEM conventions:
* https://en.bem.info/methodology/
* Although the CSS and HTML are implemented by the component, they should be regarded as
* totally decoupled.
*
* Not only does this force us to write better structured css, it also allows for future
* reusability in many different ways like:
* - disabling shadow DOM for a component (for water proof encapsulation can be combined with
* a build step)
* - easier translation to more flexible, WebComponents agnostic solutions like JSS
* (allowing extends, mixins, reasoning, IDE integration, tree shaking etc.)
* - export to a CSS module for reuse in an outer context
*
*
* Please note that the HTML structure is purposely 'loose', allowing multiple design systems
* to be compatible
* with the CSS component.
* Note that every occurence of '::slotted(*)' can be rewritten to '> *' for use in an other
* context
*/
/**
* {block} .form-field
*
* Structure:
* - {element} .form-field__label : a wrapper element around the projected label
* - {element} .form-field__help-text (optional) : a wrapper element around the projected
* help-text
* - {block} .input-group : a container around the input element, including prefixes and
* suffixes
* - {element} .form-field__feedback (optional) : a wrapper element around the projected
* (validation) feedback message
*
* Modifiers:
* - {state} [disabled] when .form-control (<input>, <textarea> etc.) has disabled set
* to true
* - {state} [filled] whether <input> has a value
* - {state} [touched] whether the user had blurred the field once
* - {state} [dirty] whether the value has changed since initial value
*
* TODO: update states below
* These classes are now attributes. Check them agains the new attribute names inside ValidateMixin
* and InteractionStateMixin. Some states got renamed. Make sure to use the correct ones!
* - {state} .state-focused: when .form-control (<input>, <textarea> etc.) <input> has focus
* - {state} .state-invalid: when input has error(s) (regardless of whether they should be
* shown to the user)
* - {state} .state-error: when input has error(s) and this/these should be shown to the user
* - {state} .state-warning: when input has warning(s) and this/these should be shown to the
* user
* - {state} .state-info: when input has info feedback message(s) and this/these should be shown
* to the user
* - {state} .state-success: when input has success feedback message(s) and this/these should be
* shown to the user
*/
/**
* {block} .input-group
*
* Structure:
* - {element} .input-group__before (optional) : a prefix that resides outside the container
* - {element} .input-group__container : an inner container: this element contains all styling
* - {element} .input-group__prefix (optional) : a prefix that resides in the container,
* allowing it to be detectable as a :first-child
* - {element} .input-group__input : a wrapper around the form-control component
* - {block} .form-control : the actual input element (input/select/textarea)
* - {element} .input-group__suffix (optional) : a suffix that resides inside the container,
* allowing it to be detectable as a :last-child
* - {element} .input-group__bottom (optional) : placeholder element for additional styling
* (like an animated line for material design input)
* - {element} .input-group__after (optional) : a suffix that resides outside the container
*/
static get styles() {
return [
css`
/**********************
{block} .form-field
********************/
:host {
display: block;
}
:host([hidden]) {
display: none;
}
:host([disabled]) {
pointer-events: none;
}
:host([disabled]) .form-field__label ::slotted(*),
:host([disabled]) .form-field__help-text ::slotted(*) {
color: var(--disabled-text-color, #767676);
}
/***********************
{block} .input-group
*********************/
.input-group__container {
display: flex;
}
.input-group__input {
flex: 1;
display: flex;
}
/***** {state} :disabled *****/
:host([disabled]) .input-group ::slotted([slot='input']) {
color: var(--disabled-text-color, #767676);
}
/***********************
{block} .form-control
**********************/
.input-group__container > .input-group__input ::slotted(.form-control) {
flex: 1 1 auto;
margin: 0; /* remove input margin in Safari */
font-size: 100%; /* normalize default input font-size */
}
`,
];
}
/**
* This function exposes descripion elements that a FormGroup should expose to its
* children. See FormGroupMixin.__getAllDescriptionElementsInParentChain()
* @return {Array.<HTMLElement>}
* @protected
*/
// Returns dom references to all elements that should be referred to by field(s)
_getAriaDescriptionElements() {
return [this._helpTextNode, this._feedbackNode];
}
/**
* Allows to add extra element references to aria-labelledby attribute.
* @param {HTMLElement} element
* @param {{idPrefix?:string; reorder?: boolean}} customConfig
*/
addToAriaLabelledBy(element, { idPrefix = '', reorder = true } = {}) {
// eslint-disable-next-line no-param-reassign
element.id = element.id || `${idPrefix}-${this._inputId}`;
if (!this._ariaLabelledNodes.includes(element)) {
this._ariaLabelledNodes = [...this._ariaLabelledNodes, element];
// This value will be read when we need to reflect to attr
/** @type {boolean} */
this.__reorderAriaLabelledNodes = Boolean(reorder);
}
}
/**
* Allows to remove element references from aria-labelledby attribute.
* @param {HTMLElement} element
*/
removeFromAriaLabelledBy(element) {
if (this._ariaLabelledNodes.includes(element)) {
this._ariaLabelledNodes.splice(this._ariaLabelledNodes.indexOf(element), 1);
this._ariaLabelledNodes = [...this._ariaLabelledNodes];
// This value will be read when we need to reflect to attr
/** @type {boolean} */
this.__reorderAriaLabelledNodes = false;
}
}
/**
* Allows to add element references to aria-describedby attribute.
* @param {HTMLElement} element
* @param {{idPrefix?:string; reorder?: boolean}} customConfig
*/
addToAriaDescribedBy(element, { idPrefix = '', reorder = true } = {}) {
// eslint-disable-next-line no-param-reassign
element.id = element.id || `${idPrefix}-${this._inputId}`;
if (!this._ariaDescribedNodes.includes(element)) {
this._ariaDescribedNodes = [...this._ariaDescribedNodes, element];
// This value will be read when we need to reflect to attr
/** @type {boolean} */
this.__reorderAriaDescribedNodes = Boolean(reorder);
}
}
/**
* Allows to remove element references from aria-describedby attribute.
* @param {HTMLElement} element
*/
removeFromAriaDescribedBy(element) {
if (this._ariaDescribedNodes.includes(element)) {
this._ariaDescribedNodes.splice(this._ariaDescribedNodes.indexOf(element), 1);
this._ariaDescribedNodes = [...this._ariaDescribedNodes];
// This value will be read when we need to reflect to attr
/** @type {boolean} */
this.__reorderAriaLabelledNodes = false;
}
}
/**
* @param {string} slotName
* @return {HTMLElement | undefined}
*/
__getDirectSlotChild(slotName) {
return /** @type {HTMLElement[]} */ (Array.from(this.children)).find(
el => el.slot === slotName,
);
}
_dispatchInitialModelValueChangedEvent() {
// When we are not a fieldset / choice-group, we don't need to wait for our children
// to send a unified event
if (this._repropagationRole === 'child') {
return;
}
// Initially we don't repropagate model-value-changed events coming
// from children. On firstUpdated we re-dispatch this event to maintain
// 'count consistency' (to not confuse the application developer with a
// large number of initial events). Initially the source field will not
// be part of the formPath but afterwards it will.
/** @type {boolean} */
this.__repropagateChildrenInitialized = true;
this.dispatchEvent(
new CustomEvent('model-value-changed', {
bubbles: true,
detail: /** @type {ModelValueEventDetails} */ ({
formPath: [this],
initialize: true,
isTriggeredByUser: false,
}),
}),
);
}
/**
* Hook for Subclassers to add logic before repropagation
* @configurable
* @param {CustomEvent} ev
* @protected
*/
// eslint-disable-next-line class-methods-use-this, no-unused-vars
_onBeforeRepropagateChildrenValues(ev) {}
/**
* @param {CustomEvent} ev
*/
__repropagateChildrenValues(ev) {
// Allows sub classes to internally listen to the children change events
// (before stopImmediatePropagation is called below).
this._onBeforeRepropagateChildrenValues(ev);
// Normalize target, we also might get it from 'portals' (rich select)
const target = (ev.detail && ev.detail.element) || ev.target;
const isEndpoint =
this._isRepropagationEndpoint || this._repropagationRole === 'choice-group';
// Prevent eternal loops after we sent the event below.
if (target === this) {
return;
}
// A. Stop sibling handlers
//
// Make sure our sibling event listeners (added by Application developers) will not get
// the child model-value-changed event, but the repropagated one at the bottom of this
// method
ev.stopImmediatePropagation();
// B1. Are we still initializing? If so, halt...
//
// Stop repropagating children events before firstUpdated and make sure we de not
// repropagate init events of our children (we already sent our own
// initial model-value-change event in firstUpdated)
const isGroup = this._repropagationRole !== 'child'; // => fieldset or choice-group
const isSelfInitializing = isGroup && !this.__repropagateChildrenInitialized;
const isChildGroupInitializing = ev.detail && ev.detail.initialize;
if (isSelfInitializing || isChildGroupInitializing) {
return;
}
// B2. Are we a single choice choice-group? If so, halt when target unchecked
// and something else is checked, meaning we will get
// another model-value-changed dispatch for the checked target
//
// We only send the checked changed up (not the unchecked). In this way a choice group
// (radio-group, checkbox-group, select/listbox) acts as an 'endpoint' (a single Field)
// just like the native <select>
if (!this._repropagationCondition(target)) {
return;
}
// C1. We are ready to dispatch. Create a formPath
//
// Compute the formPath. Choice groups are regarded 'end points'
let parentFormPath = [];
if (!isEndpoint) {
parentFormPath = (ev.detail && ev.detail.formPath) || [target];
}
const formPath = [...parentFormPath, this];
// C2. Finally, redispatch a fresh model-value-changed event from our host, consumable
// for an Application Developer
//
// Since for a11y everything needs to be in lightdom, we don't add 'composed:true'
this.dispatchEvent(
new CustomEvent('model-value-changed', {
bubbles: true,
detail: /** @type {ModelValueEventDetails} */ ({
formPath,
isTriggeredByUser: Boolean(ev.detail?.isTriggeredByUser),
}),
}),
);
}
/**
* Based on provided target, this condition determines whether received model-value-changed
* event should be repropagated
* @param {FormControlHost} target
* @protected
* @overridable
*/
// eslint-disable-next-line class-methods-use-this
_repropagationCondition(target) {
return Boolean(target);
}
/**
* @overridable
* A Subclasser should only override this method if the interactive element
* ([slot=input]) is not a native element(like input, textarea, select)
* that already receives focus on label click.
*
* @example
* _onLabelClick() {
* this._invokerNode.focus();
* }
* @protected
*/
// eslint-disable-next-line class-methods-use-this
_onLabelClick() {}
};
export const FormControlMixin = dedupeMixin(FormControlMixinImplementation);