| 1 | /*
|
| 2 | * Copyright 2020 Adobe. All rights reserved.
|
| 3 | * This file is licensed to you under the Apache License, Version 2.0 (the "License");
|
| 4 | * you may not use this file except in compliance with the License. You may obtain a copy
|
| 5 | * of the License at http://www.apache.org/licenses/LICENSE-2.0
|
| 6 | *
|
| 7 | * Unless required by applicable law or agreed to in writing, software distributed under
|
| 8 | * the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR REPRESENTATIONS
|
| 9 | * OF ANY KIND, either express or implied. See the License for the specific language
|
| 10 | * governing permissions and limitations under the License.
|
| 11 | */
|
| 12 |
|
| 13 | export function getScrollParent(node: Element): Element {
|
| 14 | if (isScrollable(node)) {
|
| 15 | node = node.parentElement;
|
| 16 | }
|
| 17 |
|
| 18 | while (node && !isScrollable(node)) {
|
| 19 | node = node.parentElement;
|
| 20 | }
|
| 21 |
|
| 22 | return node || document.scrollingElement || document.documentElement;
|
| 23 | }
|
| 24 |
|
| 25 | export function isScrollable(node: Element): boolean {
|
| 26 | let style = window.getComputedStyle(node);
|
| 27 | return /(auto|scroll)/.test(style.overflow + style.overflowX + style.overflowY);
|
| 28 | }
|