| // Copyright 2017 The Chromium Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| /** |
| * @fileoverview APIs used for the scroll workaround. See crbug.com/554257. |
| */ |
| |
| goog.provide('__crWeb.scrollHelper'); |
| |
| /** Beginning of anonymous object */ |
| (function() { |
| |
| /** @private */ |
| var webViewScrollViewIsDragging_ = false; |
| |
| /** |
| * Tracks whether user is in the middle of scrolling/dragging. If user is |
| * scrolling, ignore window.scrollTo() until user stops scrolling. |
| */ |
| __gCrWeb['setWebViewScrollViewIsDragging'] = function(state) { |
| webViewScrollViewIsDragging_ = state; |
| }; |
| |
| /** @private */ |
| var originalWindowScrollTo_ = window.scrollTo; |
| |
| /** |
| * Wraps the original window.scrollTo() to suppress it as long as |
| * webViewScrollViewIsDragging is true. Use apply() with called |
| * arguments since there are two variants of window.scrollTo: |
| * scrollTo(x, y) and scrollTo(options). |
| */ |
| window.scrollTo = function() { |
| if (webViewScrollViewIsDragging_) return; |
| originalWindowScrollTo_.apply(null, arguments); |
| }; |
| |
| }()); // End of anonymous object |
