Source: jsdoc/node_modules/elements-sk/multi-select-sk/multi-select-sk.js

// Copyright 2018 Google LLC
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     https://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
/** @module elements-sk/multi-select-sk
 *
 * @description <h2><code>multi-select-sk</code></h2>
 *
 * <p>
 *   Clicking on the children will cause them to be selected.
 * </p>
 *
 * <p>
 *   The multi-select-sk elements monitors for the addition and removal of child
 *   elements and will update the 'selected' property as needed. Note that it
 *   does not monitor the 'selected' attribute of child elements, and will not
 *   update the 'selected' property if they are changed directly.
 * </p>
 *
 * @example
 *
 *   <multi-select-sk>
 *     <div></div>
 *     <div></div>
 *     <div selected></div>
 *     <div></div>
 *     <div selected></div>
 *   </multi-select-sk>
 *
 * @evt selection-changed - Sent when an item is clicked and the selection is changed.
 *   The detail of the event contains the indices of the children elements:
 *
 *   <pre>
 *     detail: {
 *       selection: [2,4],
 *     }
 *   </pre>
 *
 */
import { define } from '../define';
import { upgradeProperty } from '../upgradeProperty';
export class MultiSelectSk extends HTMLElement {
    constructor() {
        super();
        // Keep _selection up to date by monitoring DOM changes.
        this._obs = new MutationObserver(() => this._bubbleUp());
        this._selection = [];
    }
    connectedCallback() {
        upgradeProperty(this, 'selection');
        upgradeProperty(this, 'disabled');
        this.addEventListener('click', this._click);
        this._obs.observe(this, {
            childList: true,
        });
        this._bubbleUp();
    }
    disconnectedCallback() {
        this.removeEventListener('click', this._click);
        this._obs.disconnect();
    }
    /** Whether this element should respond to input. */
    get disabled() { return this.hasAttribute('disabled'); }
    set disabled(val) {
        if (val) {
            this.setAttribute('disabled', '');
            this.selection = [];
        }
        else {
            this.removeAttribute('disabled');
            this._bubbleUp();
        }
    }
    /**
     * A sorted array of indices that are selected or [] if nothing is selected.
     * If selection is set to a not sorted array, it will be sorted anyway.
     */
    get selection() { return this._selection; }
    set selection(val) {
        if (this.disabled) {
            return;
        }
        if (!val || !val.sort) {
            val = [];
        }
        val.sort();
        this._selection = val;
        this._rationalize();
    }
    _click(e) {
        if (this.disabled) {
            return;
        }
        // Look up the DOM path until we find an element that is a child of
        // 'this', and set _selection based on that.
        let target = e.target;
        while (target && target.parentElement !== this) {
            target = target.parentElement;
        }
        if (!target || target.parentElement !== this) {
            return; // not a click we care about
        }
        if (target.hasAttribute('selected')) {
            target.removeAttribute('selected');
        }
        else {
            target.setAttribute('selected', '');
        }
        this._bubbleUp();
        this.dispatchEvent(new CustomEvent('selection-changed', {
            detail: {
                selection: this._selection,
            },
            bubbles: true,
        }));
    }
    // Loop over all immediate child elements update the selected attributes
    // based on the selected property of this selement.
    _rationalize() {
        // assume this.selection is sorted when this is called.
        let s = 0;
        for (let i = 0; i < this.children.length; i++) {
            if (this.children[i].getAttribute('tabindex') == null) {
                this.children[i].setAttribute('tabindex', '0');
            }
            if (this._selection[s] === i) {
                this.children[i].setAttribute('selected', '');
                s++;
            }
            else {
                this.children[i].removeAttribute('selected');
            }
        }
    }
    // Loop over all immediate child elements and find all with the selected
    // attribute.
    _bubbleUp() {
        this._selection = [];
        if (this.disabled) {
            return;
        }
        for (let i = 0; i < this.children.length; i++) {
            if (this.children[i].hasAttribute('selected')) {
                this._selection.push(i);
            }
        }
        this._rationalize();
    }
}
;
define('multi-select-sk', MultiSelectSk);
;
//# sourceMappingURL=multi-select-sk.js.map