Reputation: 245
I am trying to use links in my header to scroll to different parts of my App with scrollIntoView. The header is a child of App. I am getting a TypeError saying the variable I am trying to save the id to is undefined. Can someone please help me to determine what I am doing wrong? I think I may have to use ComponentDidMount, but I'm not sure how to do it, if that is even the fix. I am going to have to do this with all my header links.
//ERROR bundle.js:152 Uncaught TypeError: Cannot read property 'scrollIntoView' of null at App.getScrollLocations (bundle.js:152) at onClick (bundle.js:19957) at Object.ReactErrorUtils.invokeGuardedCallback (bundle.js:4660) at executeDispatch (bundle.js:4460) at Object.executeDispatchesInOrder (bundle.js:4483) at executeDispatchesAndRelease (bundle.js:3913) at executeDispatchesAndReleaseTopLevel (bundle.js:3924) at Array.forEach () at forEachAccumulated (bundle.js:4760) at Object.processEventQueue (bundle.js:4129) ///////
//App
class App extends Component {
constructor(props) {
super(props);
this.closeModal = this.closeModal.bind(this);
this.openModal = this.openModal.bind(this);
this.getScrollLocations = this.getScrollLocations.bind(this);
this.state = {
open: false,
projects: Service,
selectedProject: Service[0]
}
}
closeModal(event) {
this.setState({open: false});
}
openModal(project) {
this.setState({
open: true,
selectedProject: project
});
}
///////////// scroll function //////////////
getScrollLocations() {
const whatIDo = document.getElementById('.whatIdo');
console.log(whatIDo)
whatIDo.scrollIntoView();
}
render() {
const show = {
display: 'block'
};
const hide = {
display: 'none'
};
return (
<div>
<div style={this.state.open === false ? hide : show}>
<Modal
value={this.state.open}
closeModal={this.closeModal}
project={this.state.selectedProject}
/>
</div>
<Header
//////////// FUNCTION PASSED TO HEADER ///////////////
getScrollLocations={this.getScrollLocations}
/>
<Intro />
/////////////// ELEMENT I AM TARGETING /////////////////
<WhatIDo id="whatIDo" />
<WhoIAm />
<Gallery
value={this.state.open}
projects={this.state.projects}
openModal={this.openModal}
/>
<Contact />
<Footer />
</div>
);
}
}
//Header
const header = (props) => {
console.log(props);
return (
<div className="header">
<div className="header-name">
XXXXXXX XXXXXXX
</div>
<div className="header-links">
<ul>
<li>Intro</li>
<li
///////////// FUNCTION CALL ON CLICK /////////////////
onClick={() => props.getScrollLocations()}
>What I do</li>
<li>Who I am</li>
<li>My Work</li>
<li>Contact</li>
</ul>
</div>
</div>
)
}
Upvotes: 18
Views: 32264
Reputation: 983
I used the following module to achieve this in react:
https://www.npmjs.com/package/scroll-into-view-if-needed
It works much as you'd expect using in-page anchor links and can be used with react-router without problems.
import React from 'react';
import PropTypes from 'prop-types';
import scrollIntoViewIfNeeded from 'scroll-into-view-if-needed';
/*
SCROLL INTO VIEW
Purpose:
This modular component enables hash links
eg. (www.xyz.com/somepage#someID)
and plays nice with react router 4
Usage:
Wrap this component around a single div with an ID
Example:
<ScrollIntoView id={this.props.location.hash}>
<div id="someID">
... loads of content...
</div>
</ScrollIntoView>
<a href="/somepage#someID"> IN-PAGE ANCHOR </a>
*/
class ScrollIntoView extends React.Component {
componentDidMount() {
this.scroll();
}
componentDidUpdate() {
this.scroll();
}
scroll() {
const { id } = this.props;
//console.log('ID is: '+id);
if (!id) {
return;
}
const element = document.querySelector(id);
if (element) {
// this just jumps to the element
// see support:
//element.scrollIntoView({block: "end", behavior: "smooth"});
//If Firefox...
if (navigator.userAgent.indexOf("Firefox") > 0) {
//...use native smooth scrolling.
element.scrollIntoView({block: "end", behavior: "smooth"});
// If its any other browser, use custom polyfill...
}else{
//... luckily I have this handy polyfill...
scrollIntoViewIfNeeded(element, false, {
duration: 150
});
// (⌐■_■
}
}
}
render() {
return this.props.children;
}
}
ScrollIntoView.propTypes = {
id: PropTypes.string.isRequired,
children: PropTypes.oneOfType([
PropTypes.array.isRequired,
PropTypes.object.isRequired
])
};
export default ScrollIntoView;
Here is an example of that in action: https://anthonycregan.co.uk/portfolio
Upvotes: 5