vscode/extensions/markdown-language-features/preview-src/activeLineMarker.ts

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2024-11-15 06:29:18 +00:00
/*---------------------------------------------------------------------------------------------
* Copyright (c) Microsoft Corporation. All rights reserved.
* Licensed under the MIT License. See License.txt in the project root for license information.
*--------------------------------------------------------------------------------------------*/
import { getElementsForSourceLine } from './scroll-sync';
export class ActiveLineMarker {
private _current: any;
onDidChangeTextEditorSelection(line: number, documentVersion: number) {
const { previous } = getElementsForSourceLine(line, documentVersion);
this._update(previous && (previous.codeElement || previous.element));
}
private _update(before: HTMLElement | undefined) {
this._unmarkActiveElement(this._current);
this._markActiveElement(before);
this._current = before;
}
private _unmarkActiveElement(element: HTMLElement | undefined) {
if (!element) {
return;
}
element.classList.toggle('code-active-line', false);
}
private _markActiveElement(element: HTMLElement | undefined) {
if (!element) {
return;
}
element.classList.toggle('code-active-line', true);
}
}