At first this seems to be duplicate question answered here but there is more that need to be figured out.
How can I resolve below given [Violation] warning in google chrome console?
[Violation] Added non-passive event listener to a scroll-blocking 'mousewheel' event. Consider marking event handler as 'passive' to make the page more responsive.
Here is the code snippet that works but with the above mentioned [Violation] warning.
$.fn.isolatedScroll = function() {
this.on('mousewheel DOMMouseScroll', function (e) {
let delta = e.wheelDelta || (e.originalEvent && e.originalEvent.wheelDelta) || -e.detail,
bottomOverflow = this.scrollTop + $(this).outerHeight() - this.scrollHeight >= 0,
topOverflow = this.scrollTop <= 0;
if ((delta < 0 && bottomOverflow) || (delta > 0 && topOverflow)) {
e.preventDefault();
}
});
return this;
};
$('.js-isolated-scroll').isolatedScroll()
// Nothing to check here as it's just repeating <p> tags
function multiplyNode(node, count, deep) {
for (var i = 0, copy; i < count - 1; i++) {
copy = node.cloneNode(deep);
node.parentNode.insertBefore(copy, node);
}
}
multiplyNode(document.querySelector('.p-in-fixed'), 20, true);
multiplyNode(document.querySelector('.p-in-body'), 20, true);body{
position: relative;
background-color: #ccc !important;
padding: 20px 20px 20px 50%;
}
.fixed {
top: 20px;
left: 20px;
right: 20px;
bottom: 20px;
padding: 20px;
overflow: auto;
position: fixed;
border: 1px solid #333;
width: calc(50% - 40px);
background-color: #f8f8f8;
}<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<div class="js-isolated-scroll fixed">
<p class="p-in-fixed">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Ab accusamus aliquam, beatae blanditiis, cum dicta earum eligendi esse eum inventore iusto molestiae necessitatibus nesciunt praesentium quod ratione, similique sit voluptates.</p>
</div>
<p class="p-in-body">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Ab accusamus aliquam, beatae blanditiis, cum dicta earum eligendi esse eum inventore iusto molestiae necessitatibus nesciunt praesentium quod ratione, similique sit voluptates.</p>Here is how I tried to fix it using Modernizr's passiveeventlisteners with this code Modernizr.passiveeventlisteners ? {passive:true} : false while following an answer given here. But I am getting this error message in console:
Unable to preventDefault inside passive event listener invocation.
It's clear for me that I cannot using e.preventDefault() while using {passive:true} and that make sense, I just want know how can I Prevent page scrolling when scrolling a DIV while resolving [Violation] warning in console.
Here is the code snippet that doesn't work and produces above mentioned error in console.
document.getElementById('fixed-content').addEventListener('wheel', avoidBodyScroll, Modernizr.passiveeventlisteners ? {passive:true} : false);
document.getElementById('fixed-content').addEventListener('mousewheel', avoidBodyScroll, Modernizr.passiveeventlisteners ? {passive:true} : false);
document.getElementById('fixed-content').addEventListener('DOMMouseScroll', avoidBodyScroll, Modernizr.passiveeventlisteners ? {passive:true} : false);
function avoidBodyScroll(e) {
let delta = e.wheelDelta || (e.originalEvent && e.originalEvent.wheelDelta) || -e.detail,
bottomOverflow = this.scrollTop + $(this).outerHeight() - this.scrollHeight >= 0,
topOverflow = this.scrollTop <= 0;
if ((delta < 0 && bottomOverflow) || (delta > 0 && topOverflow)) {
e.preventDefault();
}
}
// Nothing to check here as it's just repeating <p> tags
function multiplyNode(node, count, deep) {
for (var i = 0, copy; i < count - 1; i++) {
copy = node.cloneNode(deep);
node.parentNode.insertBefore(copy, node);
}
}
multiplyNode(document.querySelector('.p-in-fixed'), 20, true);
multiplyNode(document.querySelector('.p-in-body'), 20, true);body{
position: relative;
background-color: #ccc !important;
padding: 20px 20px 20px 50%;
}
.fixed {
top: 20px;
left: 20px;
right: 20px;
bottom: 20px;
padding: 20px;
overflow: auto;
position: fixed;
border: 1px solid #333;
width: calc(50% - 40px);
background-color: #f8f8f8;
}<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css" integrity="sha384-BVYiiSIFeK1dGmJRAkycuHAHRg32OmUcww7on3RYdg4Va+PmSTsz/K68vbdEjh4u" crossorigin="anonymous">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.1/jquery.min.js"></script>
<script>
/*! modernizr 3.5.0 (Custom Build) | MIT *
* https://modernizr.com/download/?-passiveeventlisteners-setclasses !*/
!function(e,n,s){function o(e,n){return typeof e===n}function a(){var e,n,s,a,t,f,l;for(var c in r)if(r.hasOwnProperty(c)){if(e=[],n=r[c],n.name&&(e.push(n.name.toLowerCase()),n.options&&n.options.aliases&&n.options.aliases.length))for(s=0;s<n.options.aliases.length;s++)e.push(n.options.aliases[s].toLowerCase());for(a=o(n.fn,"function")?n.fn():n.fn,t=0;t<e.length;t++)f=e[t],l=f.split("."),1===l.length?Modernizr[l[0]]=a:(!Modernizr[l[0]]||Modernizr[l[0]]instanceof Boolean||(Modernizr[l[0]]=new Boolean(Modernizr[l[0]])),Modernizr[l[0]][l[1]]=a),i.push((a?"":"no-")+l.join("-"))}}function t(e){var n=l.className,s=Modernizr._config.classPrefix||"";if(c&&(n=n.baseVal),Modernizr._config.enableJSClass){var o=new RegExp("(^|\\s)"+s+"no-js(\\s|$)");n=n.replace(o,"$1"+s+"js$2")}Modernizr._config.enableClasses&&(n+=" "+s+e.join(" "+s),c?l.className.baseVal=n:l.className=n)}var i=[],r=[],f={_version:"3.5.0",_config:{classPrefix:"",enableClasses:!0,enableJSClass:!0,usePrefixes:!0},_q:[],on:function(e,n){var s=this;setTimeout(function(){n(s[e])},0)},addTest:function(e,n,s){r.push({name:e,fn:n,options:s})},addAsyncTest:function(e){r.push({name:null,fn:e})}},Modernizr=function(){};Modernizr.prototype=f,Modernizr=new Modernizr,Modernizr.addTest("passiveeventlisteners",function(){var n=!1;try{var s=Object.defineProperty({},"passive",{get:function(){n=!0}});e.addEventListener("test",null,s)}catch(o){}return n});var l=n.documentElement,c="svg"===l.nodeName.toLowerCase();a(),t(i),delete f.addTest,delete f.addAsyncTest;for(var u=0;u<Modernizr._q.length;u++)Modernizr._q[u]();e.Modernizr=Modernizr}(window,document);
</script>
<div id="fixed-content" class="js-isolated-scroll fixed">
<p class="p-in-fixed">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Ab accusamus aliquam, beatae blanditiis, cum dicta earum eligendi esse eum inventore iusto molestiae necessitatibus nesciunt praesentium quod ratione, similique sit voluptates.</p>
</div>
<p class="p-in-body">Lorem ipsum dolor sit amet, consectetur adipisicing elit. Ab accusamus aliquam, beatae blanditiis, cum dicta earum eligendi esse eum inventore iusto molestiae necessitatibus nesciunt praesentium quod ratione, similique sit voluptates.</p>Or, Am I making things unnecessarily complicated because as it can be achieved just by using CSS?
