Possible to defer loading of jQuery?
Here is a good description of modern approach for async/defer javascript loading. But it doesn't works for inline scripts
<script type="text/javascript" src="/jquery/3.1.1-1/jquery.min.js" defer></script>
<script type="text/javascript" defer>
$(function () { // <- jquery is not yet initialized
...
});
</script>
The simplest solution for async loading was suggested by @nilskp - externalize script:
<script type="text/javascript" src="/jquery/3.1.1-1/jquery.min.js" defer></script>
<script type="text/javascript" src="resources/js/onload.js" defer></script>
Try this, which is something I edited a while ago from the jQuerify bookmarklet. I use it frequently to load jQuery and execute stuff after it's loaded. You can of course replace the url there with your own url to your customized jquery.
(function() {
function getScript(url,success){
var script=document.createElement('script');
script.src=url;
var head=document.getElementsByTagName('head')[0],
done=false;
script.onload=script.onreadystatechange = function(){
if ( !done && (!this.readyState || this.readyState == 'loaded' || this.readyState == 'complete') ) {
done=true;
success();
script.onload = script.onreadystatechange = null;
head.removeChild(script);
}
};
head.appendChild(script);
}
getScript('http://ajax.googleapis.com/ajax/libs/jquery/1.5.2/jquery.min.js',function(){
// YOUR CODE GOES HERE AND IS EXECUTED AFTER JQUERY LOADS
});
})();
I would really combine jQuery and jQuery-UI into one file and use a url to it. If you REALLY wanted to load them separately, just chain the getScripts:
getScript('http://myurltojquery.js',function(){
getScript('http://myurltojqueryUI.js',function(){
//your tab code here
})
});
As this is a top ranking question on a important subject let me be so bold to provide my own take on this based on a previous answer from @valmarv and @amparsand.
I'm using a multi-dimensional array to load the scripts. Grouping together those that have no dependencies between them:
var dfLoadStatus = 0;
var dfLoadFiles = [
["http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js"],
["http://ajax.googleapis.com/ajax/libs/jqueryui/1.8.11/jquery-ui.min.js",
"/js/somespecial.js",
"/js/feedback-widget.js#2312195",
"/js/nohover.js"]
];
function downloadJSAtOnload() {
if (!dfLoadFiles.length) return;
var dfGroup = dfLoadFiles.shift();
dfLoadStatus = 0;
for(var i = 0; i<dfGroup.length; i++) {
dfLoadStatus++;
var element = document.createElement('script');
element.src = dfGroup[i];
element.onload = element.onreadystatechange = function() {
if ( ! this.readyState ||
this.readyState == 'complete') {
dfLoadStatus--;
if (dfLoadStatus==0) downloadJSAtOnload();
}
};
document.body.appendChild(element);
}
}
if (window.addEventListener)
window.addEventListener("load", downloadJSAtOnload, false);
else if (window.attachEvent)
window.attachEvent("onload", downloadJSAtOnload);
else window.onload = downloadJSAtOnload;
It loads first jquery after it is loaded it continue to load the other scripts at once. You can add scripts easy by adding to the array anywhere on your page:
dfLoadFiles.push(["/js/loadbeforeA.js"]);
dfLoadFiles.push(["/js/javascriptA.js", "/js/javascriptB.js"]);
dfLoadFiles.push(["/js/loadafterB.js"]);