Transition does not work with height: auto.
So I need to calculate and set the block's dynamic height with JavaScript to make the transition property work.
This is an example of my code:
<div class="accordion__item">
<div class="accordion__icon">
<div class="accordion__content">
</div>
</div>
</div>
const accItems = document.querySelectorAll('.accordion__item');
accItems.forEach((item) => {
const icon = item.querySelector('.accordion__icon');
const content = item.querySelector('.accordion__content');
item.addEventListener("click", () => {
if (item.classList.contains('open')) {
item.classList.remove('open');
icon.classList.remove('open');
content.classList.remove('open');
} else {
const accOpen = document.querySelectorAll('.open');
accOpen.forEach((open) => {
open.classList.remove('open');
});
item.classList.add('open');
icon.classList.add('open');
content.classList.add('open');
}
});
});
How can I do this?
It's not ideal but there is not much we can do with transitioning height.
For a workaround, give your open class a max-height property that is larger than your expect the largest open element to get. From there you can transition the max-height property.
There are also some optimizations you can make to your event listener callback. I don't believe you need to add open to all the elements in the accordion, just the item itself.
Try something like this:
const accItems = document.querySelectorAll('.accordion__item');
accItems.forEach((item) => {
item.addEventListener("click", () => {
const openItems = document.querySelectorAll(".open")
openItems.forEach(open => open.classList.toggle("open"))
item.classList.toggle("open")
}
});
Then in your css:
.open {
max-height: 200px
}
.accordion__item {
max-height: 0;
transition: max-height 200ms ease;
}
Related
Hello I am trying to make sections animate on scroll using IntersectionObserver.
To do this i am trying to use javascript
code for css:
.hidden{
opacity: 0;
filter:blur(5px);
transform: translateX(-100%);
transition: all 1s;
}
.show {
opacity: 1;
filter:blur(0px);
transform: translateX(0);
}
code for js
const observer = new IntersectionObserver((entries) => {
entries.forEach((entry) => {
console.log(entry)
if (entry.isIntersecting) {
entry.target.classlist.add('show');
} else {
entry.target.classList.remove('show');
}
});
});
const hiddenElements = document.querySelectorAll('.hidden');
hiddenElements.forEach((el) => observer.observe(el));
code for html:
<section class="hidden"> <h1> heading </h1> </section>
after linking all the files together in html, my class hidden sections stay hidden and do not change to show
Error Message:
animater.js:5
Uncaught TypeError: Cannot read properties of undefined (reading 'add')
at animater.js:5:36
at Array.forEach (<anonymous>)
at IntersectionObserver.<anonymous> (animater.js:
2:13)
I want my code to change the sections in html with the class hidden to class show so that they animate on scrolling the page / viewing the section. Currently the code gives me the above specified error and the sections with class hidden stay with their hidden class.
you are getting error on line number 5
const observer = new IntersectionObserver((entries) => {
entries.forEach((entry) => {
console.log(entry)
if (entry.isIntersecting) {
- entry.target.classlist.add('show');
+ entry.target.classList.add('show');
} else {
entry.target.classList.remove('show');
}
});
});
const hiddenElements = document.querySelectorAll('.hidden');
hiddenElements.forEach((el) => observer.observe(el));
I've been stuck on this for a few days. I've tried different selectors and unwrapping the img in the div if that was the problem but no luck. I've been trying to make an accordion.
I'm trying to add a class of "rotate" to the img with the class of "arrow". So that when the question tag is clicked, the arrow img will also rotate.
const questionTag = document.querySelectorAll('.question')
questionTag.forEach(questionTag => {
questionTag.addEventListener('click', () => {
if (questionTag.classList.contains('open')) {
questionTag.classList.remove('open');
} else {
const questionTagOpen = document.querySelectorAll('.open');
questionTagOpen.forEach((questionTagOpen) => {
questionTagOpen.classList.remove('open');
});
questionTag.classList.add('open');
}
});
});
.question + .answer {
display: none;
overflow: hidden;
transition: all ease 1s;
}
.question.open + .answer {
display: block;
}
.arrow.rotate {
transform: rotate(180deg);
}
<div class="container">
<div class="question">How many team members can I invite?
<img class="arrow" src="./images/icon-arrow-down.svg">
</div>
<div class="answer">You can invite up to 2 additional users on the Free plan. There is no limit on
team members for the Premium plan.</div>
</div>
You're missing [0] in your code.
The arrowTag comes from document.querySelectorAll(), which returns a NodeList, you need to specify the element from that NodeList:
var questionTag = document.querySelectorAll('.question')
questionTag.forEach(questionTag => {
questionTag.addEventListener('click', () => {
if (questionTag.classList.contains('open')) {
questionTag.classList.remove('open');
} else {
const questionTagOpen = document.querySelectorAll('.open');
questionTagOpen.forEach((questionTagOpen) => {
questionTagOpen.classList.remove('open');
});
questionTag.classList.add('open');
}
});
var arrowTag = document.querySelectorAll('img.arrow')
questionTag.addEventListener('click', () => {
arrowTag[0].classList.toggle('rotate'); // missing [0] added here
});
});
The addEventListener function is applied to an event target.
Thus, you cannot apply it to the NodeList, which is stored in your arrowTag:
I want an overlay to show up when I click a search icon.
I managed to get it working using jQuery. But can't seem to get it working with javascript.
The click event does not seem to be registering and I don't know why.
I've checked all the class names so they match in the same in both the HTML and javascript
Here is the jQuery code that works:
import $ from 'jquery';
class Search {
constructor() {
this.openButton = $('.js-search-trigger');
this.closeButton = $('.search-overlay__close');
this.searchOverlay = $(".search-overlay");
this.events();
}
events() {
this.openButton.on('click', this.openOverlay.bind(this));
this.closeButton.on('click', this.closeOverlay.bind(this));
}
openOverlay() {
this.searchOverlay.addClass("search-overlay--active");
}
closeOverlay() {
this.searchOverlay.removeClass("search-overlay--active");
}
}
export default Search;
Here is the javascript code that does not work:
class Search {
constructor() {
this.openButton = document.querySelector('.js-search-trigger');
this.closeButton = document.querySelector('.search-overlay__close');
this.searchOverlay = document.querySelector('.search-overlay');
this.events();
}
events() {
this.openButton.addEventListener('click', function() {
this.openOverlay.bind(this);
});
this.closeButton.addEventListener('click', function() {
this.closeOverlay.bind(this);
});
}
openOverlay() {
this.searchOverlay.classList.add('search-overlay--active');
}
closeOverlay() {
this.searchOverlay.classList.remove('search-overlay--active');
}
}
export default Search;
No errors were shown in the javascript where the overlay was not showing.
You'll probably want to change your event listeners to use the correct this binding:
this.openButton.addEventListener("click", this.openOverlay.bind(this));
Or use an arrow function to go with your approach - but make sure you actually call the resulting function, as in the above approach the function is passed as a reference and is called. If you removed the additional () from the code below, it would be the same as writing a function out in your code normally - it would be defined, but nothing would happen.
this.openButton.addEventListener("click", () => {
this.openOverlay.bind(this)();
});
jQuery also uses collections of elements rather than single elements, so if you have multiple elements, querySelectorAll and forEach might be in order.
If we are speaking of ecmascript-6 (I see the tag), I would recommend to use arrow function to have this inherited from the above scope, and no bind is needed:
this.openButton.addEventListener('click', () =>
this.openOverlay()
);
The problems with your code are that a) the function creates new scope with its own this; b) bound methods are not being invoked.
Why Search? You're creating an Overlay. Stick with the plan.
No need to bind anything. Use Event.currentTarget if you want to.
No need to handle .open/.close if all you need is a toggle.
And the below should work (as-is) for multiple Overlays. The overlay content is up to you.
class Overlay {
constructor() {
this.toggleButtons = document.querySelectorAll('[data-overlay]');
if (this.toggleButtons.length) this.events();
}
events() {
this.toggleButtons.forEach(el => el.addEventListener('click', this.toggleOverlay));
}
toggleOverlay(ev) {
const btn = ev.currentTarget;
const sel = btn.getAttribute('data-overlay');
const overlay = sel ? document.querySelector(sel) : btn.closest('.overlay');
overlay.classList.toggle('is-active');
}
}
new Overlay();
*{margin:0; box-sizing:border-box;} html,body {height:100%; font:14px/1.4 sans-serif;}
.overlay {
background: rgba(0,0,0,0.8);
color: #fff;
position: fixed;
top: 0;
left: 0;
width: 100vw;
height: 100vh;
padding: 5vw;
transition: opacity 0.4s, visibility 0.4s;
visibility: hidden;
opacity: 0;
}
.overlay.is-active {
opacity: 1;
visibility: visible;
}
<button type="button" data-overlay="#search">OPEN #search</button>
<button type="button" data-overlay="#qa">OPEN #qa</button>
<div class="overlay" id="search">
<button type="button" data-overlay>CLOSE</button>
<h2>SEARCH</h2>
<input type="text" placeholder="Search…">
</div>
<div class="overlay" id="qa">
<button type="button" data-overlay>CLOSE</button>
<h2>Q&A</h2>
<ul><li>Lorem ipsum</li></ul>
</div>
The above is still not perfect, still misses a way to "destroy" events and not re-attach duplicate events to already initialised buttons when trying to target dynamically created ones.
Also, the use of Classes for the above task is absolutely misleading and unnecessary.
I want the div element to get the class of "showtext" when you scroll 100 pixels or less above the element. When you're 100 pixels or more above it, it has the class of "hidden".
I am trying to use a ref to access the div element, and use a method called showText to check and see when we scroll to 100 pixels or less above that div element, i'm using scrollTop for this.
Then i use componentDidMount to add a window event listener of scroll, and call my showText method.
I am new to this, so I am sure there is mistakes here and probably bad code. But any help is appreciated!
import React, {Component} from 'react';
class SlideIn extends Component{
state={
showTexts: false,
}
showText=()=>{
const node= this.showTextRef;
if(node.scollTop<=100)
this.setState({
showTexts: true
})
}
componentDidMount(){
window.addEventListener('scroll', this.showText() )
}
render(){
const intro= document.querySelector('.intro')
return(
<div classname={this.state.showTexts ? 'showText' : 'hidden'} ref={node =>this.showTextRef = node}>
{window.addEventListener('scroll', this.showText)}
<h1>You did it!</h1>
</div>
)
}
}
export default SlideIn
I have tried using this.showText in my window scroll event, and as you see above this.showText(), neither have worked. I tried to use the current property on my div ref in my showText method, and it threw a error saying the scrollTop could not define the property of null.
Again I am new to this and have never added a window event listener this way, nor have I ever used scrollTop.
Thanks for any help!
When you attach an event listener you have to pass a function as a parameter. You are calling the function directly when you add the event listener.
In essence, you need to change:
componentDidMount(){
window.addEventListener('scroll', this.showText() )
}
to:
componentDidMount(){
window.addEventListener('scroll', this.showText)
}
In your scroll listener you should check the scroll position of the window(which is the element where you are performing the scroll):
showText = () => {
if (window.scrollY <= 100) {
this.setState({
showTexts: true
});
}
}
Also, you are attaching the event listener in the render method. The render method should only contain logic to render the elements.
Pass function as parameter like
window.addEventListener('scroll', this.showText)
and remove it from return.
Then you just need to do only this in function
if(window.scrollY<=100)
this.setState({
showTexts: true
})
use your div position here
You need to use getBoundingCLientRect() to get scroll position.
window.addEventListener("scroll", this.showText); you need to pass this.showText instead of calling it.
classname has speeling mistake.
showText = () => {
const node = this.showTextRef;
const {
y = 0
} = (node && node.getBoundingClientRect()) || {};
this.setState({
showTexts: y <= 100
});
};
componentDidMount() {
window.addEventListener("scroll", this.showText);
}
render() {
const intro = document.querySelector(".intro");
return (
<div
className={this.state.showTexts ? "showText" : "hidden"}
ref={node => (this.showTextRef = node)}
>
<h1>You did it!</h1>
</div>
);
}
condesandbox of working example: https://codesandbox.io/s/intelligent-shannon-1p6sp
I've put together a working sample for you to reference, here's the link: https://codesandbox.io/embed/summer-forest-cksfh
There are few things to point out here in your code:
componentDidMount(){
window.addEventListener('scroll', this.showText() )
}
Just like mgracia has mentioned, using this.showText() means you're directly calling the function. The right way is just to use this.showText.
In showText function, the idea is you have to get how far user has scrolled from the top position of document. As it was called using:
const top = window.pageYOffset || document.documentElement.scrollTop;
now it's safe to check for your logic and set state according to the value you want, here I have put it like this:
this.setState({
showTexts: top <= 100
})
In your componentDidMount, you have to call showText once to trigger the first time page loading, otherwise when you reload the page it won't trigger the function.
Hope this help
Full code:
class SlideIn extends Component {
state = {
showTexts: false,
}
showText = () => {
// get how many px we've scrolled
const top = window.pageYOffset || document.documentElement.scrollTop;
this.setState({
showTexts: top <= 100
})
}
componentDidMount() {
window.addEventListener('scroll', this.showText)
this.showText();
}
render() {
return (
<div className={`box ${this.state.showTexts ? 'visible' : 'hidden'}`}
ref={node => this.showTextRef = node}>
<h1>You did it!</h1>
</div>
)
}
}
.App {
font-family: sans-serif;
text-align: center;
height: 2500px;
}
.box {
width: 100px;
height: 100px;
background: blue;
position: fixed;
left: 10px;
top: 10px;
z-index: 10;
}
.visible {
display: block;
}
.hidden {
display: none;
}
I am using Aurelia.js for my UI. Let's say I have the following view markup:
<tr repeat.for="item in items">
<td>${item.name}</td>
<td>${item.value}</td>
</tr>
Which is bound to a model "items". When one of the values in the model changes, I want to animate the cell where the changed value is displayed. How can I accomplish this?
This can be done with Aurelia custom attributes feature.
Create a new javascript file to describe the attribute (I called the attribute "animateonchange"):
import {inject, customAttribute} from 'aurelia-framework';
import {CssAnimator} from 'aurelia-animator-css';
#customAttribute('animateonchange')
#inject(Element, CssAnimator)
export class AnimateOnChangeCustomAttribute {
constructor(element, animator) {
this.element = element;
this.animator = animator;
this.initialValueSet = false;
}
valueChanged(newValue){
if (this.initialValueSet) {
this.animator.addClass(this.element, 'background-animation').then(() => {
this.animator.removeClass(this.element, 'background-animation');
});
}
this.initialValueSet = true;
}
}
It receives the element and CSS animator in constructor. When the value changes, it animates the element with a predefined CSS class name. The first change is ignored (no need to animate on initial load). Here is how to use this custom element:
<template>
<require from="./animateonchange"></require>
<div animateonchange.bind="someProperty">${someProperty}</div>
</template>
See the complete example in my blog or on plunkr
The creator of the crazy Aurelia-CSS-Animator over here :)
In order to do what you want you simply need to get hold of the DOM-Element and then use Aurelia's animate method. Since I don't know how you're going to edit an item, I've just used a timeout inside the VM to simulate it.
attached() {
// demo the item change
setTimeout( () => {
let editedItemIdx = 1;
this.items[editedItemIdx].value = 'Value UPDATED';
console.log(this.element);
var elem = this.element.querySelectorAll('tbody tr')[editedItemIdx];
this.animator.addClass(elem, 'background-animation').then(() => {
this.animator.removeClass(elem, 'background-animation')
});
}, 3000);
}
I've created a small plunkr to demonstrate how that might work. Note this is an old version, not containing the latest animator instance, so instead of animate I'm using addClass/removeClass together.
http://plnkr.co/edit/7pI50hb3cegQJTXp2r4m
Also take a look at the official blog post, with more hints
http://blog.durandal.io/2015/07/17/animating-apps-with-aurelia-part-1/
Hope this helps
Unfortunately the accepted answer didnt work for me, the value in display changes before any animation is done, it looks bad.
I solved it by using a binding behavior, the binding update is intercepted and an animation is applied before, then the value is updated and finally another animation is done.
Everything looks smooth now.
import {inject} from 'aurelia-dependency-injection';
import {CssAnimator} from 'aurelia-animator-css';
#inject(CssAnimator)
export class AnimateBindingBehavior {
constructor(_animator){
this.animator = _animator;
}
bind(binding, scope, interceptor) {
let self = this;
let originalUpdateTarget = binding.updateTarget;
binding.updateTarget = (val) => {
self.animator.addClass(binding.target, 'binding-animation').then(() => {
originalUpdateTarget.call(binding, val);
self.animator.removeClass(binding.target, 'binding-animation')
});
}
}
unbind(binding, scope) {
binding.updateTarget = binding.originalUpdateTarget;
binding.originalUpdateTarget = null;
}
}
Declare your animations in your stylesheet:
#keyframes fadeInRight {
0% {
opacity: 0;
transform: translate3d(100%, 0, 0);
}
100% {
opacity: 1;
transform: none
}
}
#keyframes fadeOutRight {
0% {
opacity: 1;
transform: none;
}
100% {
opacity: 0;
transform: translate3d(-100%, 0, 0)
}
}
.binding-animation-add{
animation: fadeOutRight 0.6s;
}
.binding-animation-remove{
animation: fadeInRight 0.6s;
}
You use it in your view like
<img src.bind="picture & animate">