A simple lightweight library for Angular which automatically updates links to indicate the currently active section in the viewport. Requires Angular Inviewport to be installed as well.

This is a simple library for Angular, implemented in the Angular Package Format v5.0.

npm i @thisissoon/{angular-scrollspy,angular-inviewport} --save

app.module.ts

import { InViewportModule } from '@thisissoon/angular-inviewport';
import { ScrollSpyModule } from '@thisissoon/angular-scrollspy';

@NgModule({
  imports: [InViewportModule, ScrollSpyModule.forRoot()],
})
export class AppModule {}

A working example can be found in the src folder.

app.component.html

<ul role="navigation" snScrollSpy id="foo">
  <li><a snScrollSpyItem for="foo" href="#section1">Section 1</a></li>
  <li><a snScrollSpyItem for="foo" href="#section2">Section 2</a></li>
  <li><a snScrollSpyItem for="foo" href="#section3">Section 3</a></li>
  <li><a snScrollSpyItem for="foo" href="#section4">Section 4</a></li>
</ul>

<sn-scroll-spy-section id="section1" for="foo">content goes here</sn-scroll-spy-section>
<sn-scroll-spy-section id="section2" for="foo">content goes here</sn-scroll-spy-section>
<sn-scroll-spy-section id="section3" for="foo">content goes here</sn-scroll-spy-section>
<sn-scroll-spy-section id="section4" for="foo">content goes here</sn-scroll-spy-section>

app.component.css

a {
  color: blue;
  transition: color 0.2s ease-in-out;
}

a.active {
  color: darkblue;
}

This library makes use of the Intersection Observer API which requires a polyfill to work on some browsers.

npm i intersection-observer

Or use yarn

yarn add intersection-observer

Add this somewhere in your src/polyfills.ts file

import 'intersection-observer';

Run ng serve for a dev server. Navigate to https://localhost:4200/. The app will automatically reload if you change any of the source files.

Run ng generate component component-name to generate a new component. You can also use ng generate directive|pipe|service|class|guard|interface|enum|module.

Run ng build to build the project. The build artifacts will be stored in the dist/ directory. Use the -prod flag for a production build.

Run ng test to execute the unit tests via Karma.

Run ng e2e to execute the end-to-end tests via Protractor.

This repo uses Commitizen CLI and Conventional Changelog to create commits and generate changelogs. Instead of running git commit run git cz and follow the prompts. Changelogs will then be generated when creating new releases by running npm run release.

Run npm run release to create a new release. This will use Standard Version to create a new release. Standard Version will generate / update the changelog based on commits generated using Commitizen CLI, update the version number following semantic versioning rules and then commit and tag the commit for the release. Simply run git push --follow-tags origin master.

To get more help on the Angular CLI use ng help or go check out the Angular CLI README.