devextreme/esm/__internal/ui/collection/m_item.js

HTML5 JavaScript Component Suite for Responsive Web Development

/**
 * DevExtreme (esm/__internal/ui/collection/m_item.js)
 * Version: 24.2.6
 * Build date: Mon Mar 17 2025
 *
 * Copyright (c) 2012 - 2025 Developer Express Inc. ALL RIGHTS RESERVED
 * Read about DevExtreme licensing here: https://js.devexpress.com/Licensing/
 */
import Class from "../../../core/class";
import $ from "../../../core/renderer";
import {
    each
} from "../../../core/utils/iterator";
import {
    attachInstanceToElement,
    getInstanceByElement
} from "../../../core/utils/public_component";
const INVISIBLE_STATE_CLASS = "dx-state-invisible";
const DISABLED_STATE_CLASS = "dx-state-disabled";
const ITEM_CONTENT_PLACEHOLDER_CLASS = "dx-item-content-placeholder";
const forcibleWatcher = (watchMethod, fn, callback) => {
    const filteredCallback = (() => {
        let oldValue;
        return value => {
            if (oldValue !== value) {
                callback(value, oldValue);
                oldValue = value
            }
        }
    })();
    return {
        dispose: watchMethod(fn, filteredCallback),
        force() {
            filteredCallback(fn())
        }
    }
};
class CollectionItem extends(Class.inherit({})) {
    ctor($element, options, rawData) {
        this._$element = $element;
        this._options = options;
        this._rawData = rawData;
        attachInstanceToElement($element, this, this._dispose);
        this._render()
    }
    _render() {
        const $placeholder = $("<div>").addClass("dx-item-content-placeholder");
        this._$element.append($placeholder);
        this._watchers = [];
        this._renderWatchers()
    }
    _renderWatchers() {
        this._startWatcher("disabled", this._renderDisabled.bind(this));
        this._startWatcher("visible", this._renderVisible.bind(this))
    }
    _startWatcher(field, render) {
        const rawData = this._rawData;
        const exprGetter = this._options.fieldGetter(field);
        const watcher = forcibleWatcher(this._options.watchMethod(), (() => exprGetter(rawData)), ((value, oldValue) => {
            this._dirty = true;
            render(value, oldValue)
        }));
        this._watchers.push(watcher)
    }
    setDataField() {
        this._dirty = false;
        each(this._watchers, ((_, watcher) => {
            watcher.force()
        }));
        return this._dirty
    }
    _renderDisabled(value, oldValue) {
        this._$element.toggleClass("dx-state-disabled", !!value);
        this._$element.attr("aria-disabled", !!value);
        this._updateOwnerFocus(value)
    }
    _updateOwnerFocus(isDisabled) {
        const ownerComponent = this._options.owner;
        if (ownerComponent && isDisabled) {
            ownerComponent._resetItemFocus(this._$element)
        }
    }
    _renderVisible(value, oldValue) {
        this._$element.toggleClass("dx-state-invisible", void 0 !== value && !value)
    }
    _dispose() {
        each(this._watchers, ((_, watcher) => {
            watcher.dispose()
        }))
    }
    static getInstance($element) {
        return getInstanceByElement($element, this)
    }
}
export default CollectionItem;