src/app/services/document/document.service.ts
// SPDX-License-Identifier: Apache-2.0
// Copyright (c) 2018 Georgi Marinov
//
// 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
//
// http://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.
//
import { Injectable } from '@angular/core';
/**
* Document service.
*/
@Injectable({
providedIn: 'root'
})
export class DocumentService {
/** Scroll to top button scroll threshold. */
private readonly scrollTopThreshold: number = 20;
/** Show scroll to top button when told so. */
public scrollFunction() {
const button = document.getElementById('goToTopBtn');
if (button) {
button.style.display =
(document.body.scrollTop > this.scrollTopThreshold
|| document.documentElement.scrollTop > this.scrollTopThreshold)
? 'block' : 'none';
}
}
/** Scroll to top. */
public goToTop() {
document.body.scrollTop = 0; // For Safari
document.documentElement.scrollTop = 0; // For Chrome, Firefox, IE and Opera
}
}